This blog is a review of the Pacey Performance Podcast Episode 385 – Paul Comfort

 

The majority of the episode focuses on isometric training.   Due to the amount and quality of information the full podcast review will be split up into two parts.  This is a Part 2 of 2, which will focus on practical applications of isometric training and eccentric training.   Click here to read Part 1.

Paul Comfort

 

Paul Comfort is a Reader in Strength and Conditioning and programme leader for the MSc Strength and Conditioning at the University of Salford, and is this week’s guest on the Pacey Performance Podcast. He’s here to talk to Rob about isometric testing and training, and why there has been a recent resurgence in its popularity.

 

Twitter

 

🔊 Listen to the full episode here

 

Isometric Testing & dynamic performance

”So if you look at something like the isometric mid thigh pull or the isometric squat, there’s a huge number of studies out there that show strong correlations between your ability to produce very high forces, so the peak force or peak force relative to mass, and performance in other dynamic strength tests or tasks. So 1RM squat, 1RM deadlift, snatch, power snatch, clean, power clean performance, etc. And in weightlifters, they’re almost perfect correlations, which isn’t surprising because they’re so used to getting into those positions for the isometric mid thigh pull.  But even if we look at how they relate to things like sprint performance, jump performance, there are still strong correlations there. Now correlation doesn’t mean cause and effect just because there’s a strong correlation. It doesn’t mean if we increase peak force in an isometric mid thigh pull, you will increase your 1RM performance or your sprint performance.

 

However, there are a few studies out there that do indicate that as your peak force increases, your ability to accelerate increases. Or as force at a specific time point increases, your ability to accelerate during a sprint or a jump, etc increases. Now that makes sense if we go back to your basic biomechanics, because we know that it’s your relative net impulse, with impulse being force x time and relative meaning dividing it by your body mass. As long as your body mass stays the same, if you can increase the amount of force you produce in the same given time point, your ability to accelerate will have increased.

 

 

Now when we evaluate it in a isometric task, then we’ve got to hope that the athlete can actually use that force and still produce a higher force in the same time frame when they perform their dynamic task. But if you’ve got the right balance between what you’re doing in the weight room, and their skill specific training, the sprint drills you might do, the jump training, the bounding and plyometrics. If you’ve got the right balance there, you should get that transference. No amount of work in the weight room will immediately transfer to a really highly skilled task. But even just on observation, if you get somebody much stronger and their peak force goes up and then their force at 150 milliseconds goes up, their ability to accelerate when they’re sprinting, jumping, does start to improve.

 

There is sometimes a lag time. So the problem with some of the research is that you do a four week or a six week block of training. You get to the end of that block and you retest them [without doing a deload first]. Well, actually, if you’ve used progressive overload, which we should all be doing, you’ve had a progressive increase in possibly load or intensity, definitely in volume. And therefore we’ve added fatigue across that few weeks of training, whether it’s four or six weeks. And you look at some studies, there’s not an unloading week, there’s not a deload week, but that’s what we do when we train people normally. You have an accumulation of fatigue during that three, four, five, six week buildup. And then we have a week where we back off, we deload, we taper, whatever term you want to use for it, then retest them when fatigue is dissipated.

 

 

And the reason I mention that is if you look at a lot Dr. Andy Fries early work on overreaching, over training, they really battered people. Some of their training programmes, you look at them and think how the hell did people get through that? And you find that peak force or their maximum strength is pretty stable. It doesn’t decrease dramatically. You can push people really hard and maximum force production doesn’t go down. But their ability to produce force rapidly decreases. So if we’ve got a similar approach where we’ve got a progressive increase in volume and we then test them right at the end of that block, it’s not surprising that you’re going to see a slight decrease in their ability to produce force rapidly because they’re fatigued. So we need that appropriate deload or taper before we retest.

 

And it doesn’t always happen within the research. Partly due to time constraints, partly due to them getting the athletes to actually take a bit of time off. And sometimes because people just don’t know any better, which is problematic in itself. So, there is that strong correlation, but it all comes down to your ability to produce force, high forces in a short duration, which is why it’s so important to have that. If we do an isometric testing to really try and quantify how much force they can produce in a certain time point, because that will indicate that they can generate a greater impulse and therefore if they can apply that greater impulse during sports specific tasks, we will get greater acceleration, whether that’s of their mass or whether that’s of an object they’re throwing or whatever it might be.”

 

Isometric Training

 

”Transitioning to the isometric training side. So as you’ve said right at the start, this is a complementary method of training to your traditional strength training, but just taking it back again, what are the benefits of isometric training and what areas does it plug that traditional strength training maybe doesn’t?”

 

”Well, I think one of the things that’s really useful is it’s minimally fatiguing. So because you are actually not moving through a large range of motion and you can easily control the duration of each isometric muscle action, you can minimize fatigue. It doesn’t have the eccentric component in there, which we get with traditional strength training, which while really beneficial, actually, if you are using an unfamiliar task may cause muscle damage, may cause DOMS, pain, inhibition and that’s one of the concerns with athletes when you introduce a new stimulus is if they come back in a day or two later complaining to the medical staff that they’re really sore. Some of them, if they’re not used to that type of training, we’ll be saying they’ve pulled the hamstring or they’ve pulled the groin or whatever.  No, you are just sore because you don’t train hard enough.  That’s what happens most of the time. It’s unlikely they’ll have pulled something in a structured weight training programme or resistance training programme if you’ve been appropriately progressive in nature. So it’s not as fatiguing.

 

And then the other benefit is everyone has sticking points during certain exercises. You start trying to do a squat, a deadlift, if you fail, there’s always a specific point you’ll fail at, normally somewhere midpoint through the range of motion, depending on where your weakness is. So you can train people in those weak positions and that can help them get through those sticking points.

 

 

And you can do that without adding a huge amount of extra volume. But as I mentioned earlier, and as you’ve just restated, it isn’t a substitute for your standard resistance training. Otherwise you’d have to train at so many different joint angles to get that transference throughout that full range of motion that you’d end up with all sorts of issues in terms of time.  For example, I’ve been trying to do an isometric squat. It’s taken me an hour to get all these different positions for enough repetitions with enough force while that was really counterproductive because I could have done that just with a few sets of squats doing a dynamic squatting type task.

 

So, you know, there are some benefits, but you’ve also got to take a step back and think, what do I really need from this?”

 

”What does the research say around that transference of specific positions? So if I’m training at a particular angle, what’s the transference?”

 

”Well, a lot of the early research seems to indicate that you’re looking at plus or minus 15 degrees from the joint angle you were training at. And that seems to be correct if you are just doing isometric training. Some of the more recent studies that have been published seem to show a slightly greater range, but that is when they’re combined with dynamic heavy strength training. So that probably helps with that transference, because you’re still doing other training and that’s the problem you get sometimes when we’ve got to do really well controlled studies in very controlled environments so that we know that whatever our intervention is, is what’s had the effect.

 

But then we also have to do those studies where they’re more ecologically valid. They are what we would do in an applied environment. So they are what we’re going to do with our football team, with our rugby team, with whatever that sport is. And then that’s when we seem to find that either what was done in that control lab environment doesn’t work or it doesn’t work as well; or sometimes, oh my God, this works much better because it’s in addition to other types of training. Some of the early studies on isometric training showed an increase in rate force development, but a decrease in jump performance. Well, how does that work? You would assume that if your rate force development increases, your jump performance should increase, but actually they were assessing rate of force development during a single joint isometric task. And then comparing that to jump performance where you’ve been training at zero velocity for the last six weeks.

So, and your jump height is determined by your velocity at takeoff and you are used to training at zero velocity. So is that really surprising when we think about specificity of training that your jump height decreased? No, it’s probably not. But again, look at the studies where it’s combined as an addition to your normal training and we tend to get beneficial adaptations. And it’s not just about the performance side of things, there’s a lot of research showing the benefits for isometric type training. As an analgesic, if you’ve got tendon pain before training in competition, actually to create adaptations in your tendons to make them stiffer, to increase the amount of collagen, etc. So they’re more resilient to stress strain and therefore injury.

 

However, bear in mind a tendon doesn’t know what type of muscle actions are occurring. It’s just got stress and strain applied to it.  But the benefit is it’s very, very controlled when it’s isometric. And if somebody has got a bit of pain, you can ramp that up progressively. Whereas it’s not quite the same because you suddenly throw them into a plyometric task.”

 

 

”If you look across the research, it’s pretty varied. I don’t think there is a true consensus because the studies are set up to get different results. Some are tendon related, some are for performance. If you think about it practically, if you identify where someone’s weak point is, that point that they slow down,  unintentionally during an exercise. So if you are going to use an isometric squat to supplement your dynamic squat training, find what that sticking point is. Find the point that they’re really having to grind through and you don’t need to assess velocity of the movement. That point with a heavy load where they really start struggling, we can all see that. They can tell you that posture. They know it because they thought they were going to fail at that point.

 

That’s the point that their face goes purple as well. So it’s really easy to spot. So actually doing some repetitions, not necessarily for a prolonged duration because you still want a really high effort. And again, the problem is if we do a really prolonged duration and a near maximal effort, we will induce fatigue. So you’re looking at your three to five second efforts, we know that you should be able to achieve peak isometric force in under two seconds. And from looking at all the forced time data that I’ve collected with isometric squats and mid thigh pulls, within five seconds, everyone’s force production starts to go down. So if you’re looking at a three to five second effort near maximum, I personally find that to be one of the most effective ways of getting people to get through sticking points. And we also want to train our athletes to express force rapidly.

 

So actually doing really prolonged holds may be grate for rehabilitation purposes. And if somebody’s had a niggling injury and that’s continued, that might be really, really beneficial, but from a performance point of view, doing three to five repetitions, three to five seconds per effort. And if you can assess that with a strain gauge or with a force plate setup, that will give you some additional feedback, but even without that you can tell if they’re working hard or not.  Watch an athletes’ face, are they holding their breath? Are they gasping for breath when they finished a repetition? Are they shaking during the task? Most people will. So you can see most of that without the strain gauge or without an isometric mid thigh pull. But actually if you’ve got the force plate to do this type of testing during their training you can also get people really competitive.

 

So if you and I were training, we can both, if we’re sort of a similar stature, we can both get onto a force plate, and do an isometric squat. I do a five second effort. Step away, you do a five second effort and we compete against each other. You’re really going to get maximal buy-in and maximum intent then. And you might not need to do it with your whole squad. There may be some athletes you think, right, this will be really useful for them. And again, a good way of sort of judging those joint angles based on where you perceive their weaknesses to be. And that’s easy during some of those dynamic strength exercises. You’ll really see that.”

 

Eccentric Training

 

”I’m just conscious that we’ve talked about isometrics been supplementary and not to miss out eccentric and concentric contractions, which you’ve mentioned as well. So where does eccentric focus training fit into this and what are the benefits? What we can gain from eccentric training?”

 

”So with eccentric we can again get really, really high forces being produced. We’ve got to implement that eccentric load appropriately though. And I’ll come to that in a moment. We know that if you’ve got a high eccentric load, which is greater than the load during a concentric task, that we can increase fascicle lengths. And if we can increase muscle fascicle lengths, we increase the potential for those fascicles to shorten at higher velocity. So I’ll try not to go off topic here, but if you look at the force velocity relationship, the majority of people get that wrong and I’ll hold my hands up. I’ve probably made that worse with some figures I’ve put in publications, textbooks, etc, but the force velocity relationship comes from fascicle shortening velocity and individual fascicles and the amount of force they can generate.

 

It’s not movement velocity, which is how most people interpret it. So it’s how quickly your fascicle can shorten. Now if your fascicles shorten more rapidly because they’re longer and you’ve got the optimal pennation angle for that, you will undoubtedly get a higher movement velocity from those individuals.  Eccentric training increases fascicle length because you are getting the muscles being stretched while it’s producing a high force. And that’s the key. You need a high force, so you can do tempo type eccentric training. We can get people lowering down over a prolonged period of time. That increases time under tension that may create a hypertrophic stimulus where we get more muscle mass. But it’s not truly eccentric training.  You’re moving at a really low velocity. 

 

[Personal communication with Paul: ”it’s not truly eccentric training because as was stated earlier, a high eccentric load has to be one which is greater than the load during a concentric task, in order to increase increase fascicle lengths.  tempo training prescriptions are usually around 80-85% 1RM for 3-5 seconds lower and you the lift it back up concentrically.  This is a good introduction to the controlled tempos but the load is insufficient to overload the eccentric component.] 

 

The goal of eccentrics is to get a higher force at a higher velocity but how you train that in the weight room is focus on the higher focus component. Imagine trying to squat down quickly with a high load.  That doesn’t happen if you are squatting and you put extra weight on the bar. If you want to move at high velocity, you relax and gravity accelerates you down. You can’t move any quicker than just relaxing and letting gravity push you to the floor. With safety bars and stuff like that in your power rack, obviously you don’t want to get squashed or crush your athlete.  So the key thing is if you are trying to apply really high force or using a high load, the eccentrics in that situation with multi-joint movements need to be slow and controlled.

 

Personally, if I’m doing it and I’m trying to use an eccentric overload, I’ll do a front squat because it’s so easy to drop the bar rather than a back squat. You’ve got to be good at jumping out from under that bar if you start to move too fast or have it set up inside a rack with the safety bar set just around your minimum squat, your maximum squat depth, the minimum height you’re going to achieve.

 

They’re really, really beneficial, but again, as an addition to your normal training. Now, if you’ve got no equipment and I’ll just stick with a squat as an example, because it’s probably the easiest one. If we want to create eccentric overload, go above your 1RM, set those safety pins. Go to about your maximum squat depth and do a very slow controlled squat. Probably going to take three to five seconds to get down there. If you think about when you’re going for a 1RM anyway, you squat down slowly. You don’t go down rapidly, because you’re going to get squashed. So you go down slow. If you’ve gone 10% above that (concentric 1RM), you’ll go down slower. The only problem is then you need a couple of strong people to lift that bar back up or you need to unload it and then lift it backup.

 

So it’s not always practical. There are some commercial devices on the market where you can do that and it’ll winch it back for you. But most people won’t have those. The other option is to use weight releasers, the j hooks that hang on the end of the bar, you can put weight on it. You get to the floor, they’ve got an angle on them, so they’ll actually flip off when you get to the bottom. Just make sure you set the height of those weight releasers, five to eight centimetres longer than you need so that when you get to the bottom of your squat or whatever lift you are doing, that they do release and make sure you’re symmetrical when you squat down because if one comes off one side and not the other, you’re in a whole world of trouble there.

 

 

So practice it with the warm-up weights and slowly build up. And you’ve got a whole range of things you can do with that. You can do it to almost try and potentiate or enhance your propulsive phase. So you could put 80% of your 1RM on the bar, 30% of your concentric or your traditional 1RM on the weight releases, you’ve got 110% 1RM. Squat down, then release, and then you come up as explosively or fast as you can. You can use it for hypertrophy as well. So we get that increased time under tension on the way down and we can use it for actually just getting that higher eccentric stimulus. As long as you squat, you get back to the top and then two people hook the weights back on for you.

 

The nice thing is for that you can end up doing that as a cluster set. Somebody put the weights on, you then pick the bar back up, step back, squat again. It takes a little bit longer, but actually you do less volume if you’re doing that high loads eccentric type training because it does create some muscle damage.

 

Now the other thing to bear in mind with this is that muscle damage is not a bad thing because it gives you the repeated bout effect. And it’s not just from eccentric training. You get that just from a novel stimulus. So if you’ve been focusing bilateral training, front squat, back squats, deadlifts, and you suddenly throw in a load of split squats, lunges, rear elevated split squats, you’ll ache in different places. The next day you’ll feel it more in your glutes and you groin, etc, because you’re stabilizing.

 

That’s not because it was a much higher load. It might have been a lower load overall. If you work out the total load lifted, it might be a lower volume. But it’s a novel stimulus. So when you introduce a novel stimulus, whether eccentric or whether they’re just going from bilateral dominant to unilateral, ideally build it in progressively because you will get a little bit sore, but that initial bout of, especially if it’s eccentric training, protects you against some of that muscle damage and the soreness and the inhibition during the subsequent bout. So your first bout, do a really low volume. If you’re doing it with squats, maybe do it on your first repetition of a squat or weight releasers. So if you’re training at 80% of 1RM, you put that extra 30% on, so you lower 110% your 1RM.

 

Do do it for one rep. Your first rep of a set and do it on the first rep, maybe the three or four sets. That is likely to give you a protective effect. Next time you can do it within the set. You know, you can cluster your set. If you’re doing sets of six, rep one as the weight releases on, then you do two and three normally, rank the bar, put the weight releases back on, do rep four with the weight releases five and six or without you’ve doubled the volume of eccentric training. So build it up progressively, because the last thing you want is your athletes coming back in telling you how much they’re aching the next day, turning around to the coach saying that they’re in bits, turning around to the medical staff because they won’t want you doing that type of training again, but it can be really beneficial.

 

And the few studies that are out there that there’s one by Mellissa Harden, where she used a control group trained athletes and some very well trained athletes. It was some GB cyclists, and they showed within a four week period substantial improvements in maximum and rapid force production from doing that type of training, using an eccentric leg press. Now there is an issue with that. No one else has access to that eccentric leg press apart from British cycling, but hey it worked. It shows, you know, the theory holds true. There’s a couple of studies by Simon Walker, which I think both Rob Newton, Keijo Häkkinen and Gregory Haff were part of that research group at that point, looking at different types of eccentric training in a more applied environment, more ecologically valid. So not just isolated, single joint eccentric training. And again, they’ve shown big increases in a short duration.

 

But again with a relatively conservative loading paradigm that they’ve used and I think that’s the key thing is you have to do a small amount because we know it will create some muscle damage. So be conservative with it. A lot of the research, researchers will say, we need to get this stimulus. We need to make sure it has a positive effect, but you know, if you turn around, look at some of the early studies on Nordics where they were doing 50 plus repetitions in a week, or sets of 10. I know after three, my subsequent reps are pretty poor because it feels like everything’s going to cramp up. And we now know that those lower volumes are maybe not quite as effective, but you get much better adherence and longer term, they will be more effective.

 

So you’ve really got to be conservative with how you apply that eccentric load. There’s lots of different ways to do it. But there are some pretty simple and easy to apply options in a normal setting if you haven’t got specialist equipment. And the weight releasers you can buy those for probably 200 pounds or if you know anybody that’s good with metal work, they can probably make some for you.”

 

Top 5 Take Away Points:

Paul Comfort Research Gate

This blog is a review of the Pacey Performance Podcast Episode 381 – Alistair McBurnie & Tom Dos’Santos

 

Alistair and Tom are interviewed in a two part series (Episode 380 and 381).  Episode 380 focused more on Deceleration ability.  Episode 381 focuses on change of direction ability.

 

I’ve created a three part blog series out of it.  In Part 1 and Part 2 the full script of the podcast was included for Episode 380.  In this Part 3 blog an edited version is included with the key take home points from Episode 381.

 

 

Tom Dos’Santo

 

Tom is a lecturer at Manchester Metropolitan University, where he teaches strength conditioning and sports biomechanics. Previously, he’s worked at the University of Salford, and England Northwest and Manchester Thunder netball squads.

 

Twitter

 

🔊 Listen to the full episode here

1. Initial Acceleration – to initiate the movement
2. Preliminary Deceleration – depending on the angle (particularly for more aggressive COD anything 60 degrees and above)
3. Preparatory postural adjustments – stride length and preparatory positions to optimise final foot plant (there will be some potential braking over the penultimate step and prior steps
4. Execution phase – final foot plant – then re-accelerate

 

There are probably five or six different change of direction actions during the execution phase.

 

1. sidestep cutting action – involves lateral foot plant abducting at the hip and pushing off towards the opposite direction
2. cross-over cut – medial foot placement on the same limb and push off in the same direction
3. shuffle step – a series of lateral foot plants – we see that from an evasive perspective (rug
4. split step (jump cut) – jump into the cut and push off that one limb, or land bilaterally and then push off one limb
5. spin maneuver– typically a 270 degrees blind side turn- popular in ball carrying sports to avoid being tackled
6. Pivot – turn to 110-120 degrees or more performed bilaterally or unilaterally
7. Deceleration – which is an agility action in its own right

 

Performance-Injury Trade Off

 

Some of the technical characteristics that are required for faster performance could be at odds with potential increased knee joint loading.

 

There is always going to be some injury risk with changing direction.

 

The faster we run the greater the knee joint load so typically we need to reduce our momentum into that, so the penultimate foot contact is key.  I believe that a lot of the poor postures adopted in that final foot contact are a by product of sub-optimal positioning on those preparatory steps, particularly in the penultimate foot contact.  I think it’s a really important step to put you in the optimal position to execute an optimal final foot contact.

 

Penultimate Foot Contact

 

We encourage EARLIER BRAKING particularly with these sharper COD as it’s a safer strategy with the penultimate foot contact because we decelerate in the sagittal plane, the knee joint is in a stronger position, GRF vectors are aligned with the knee joint centre, and we go through substantially greater range of motion (typically you go through double the amount of knee flexion, around 10-120 with the penultimate foot contact- PFC 100–120° versus FFC 20–60°) which equals greater angular displacement. Thus, based on the work-energy principle, ↑ work = greater reduction in kinetic energy and ↓ velocity.

 

Figure 1. The image on the left illustrates final foot contact (FFC), and the image on the right illustrates penultimate foot contact (PFC).

 

Final Foot Contact

 

If we think about the Final Foot Contact (FFC) you are asking the limb to go from a rapid braking phase to a rapid transition into a propulsive phase, so asking it to do two things during ground contact, whereas the PFC can focus purely on braking, and it goes through increased range of motion which is a safer strategy.

 

For a sharper turn (180 degree) we encourage to decelerate more in the anti-penultimate step, start rotating in the PFC to start lining you up in the correct position.

 

Brake early and lower your centre of mass

 

That’s going to put you in the optimal position to create that perpendicular force with a wide lateral foot plant in order to change inertia and accelerate laterally or medially in this sense.  By having a wide lateral foot plant we need to acknowledge we are going to increase the moment arm in the frontal plane, so that’s going to increase knee valgus loading, so there is probably this Goldilocks affect- not too wide but not too narrow.

 

 

Frontal Trunk control

 

Another performance-injury trade off.  If your objective is to have the greatest exit Velocity we should be encouraging medial trunk lean.  However, this is the argument that we need to ”drop the shoulder” which is a deceitful maneuver to unbalance and fool your opponent however we do get increased moment arm in the frontal plane and that is going to increase the knee valgus

 

If the objective is to complete the task as fast as possible we try and rotate early towards the direction of travel.

 

Hip Extension and Knee Flexion Paradox

 

If we want to decrease the risk of injury we just need to ask the athlete to run slow and land really softly.

 

Slower athletes display lower knee joint loads and go through greater knee and hip flexion, they distribute the load further up the chain.  Faster athletes, make ground contact/land in initial hip flexion, they don’t go through any further hip flexion so maintain the isometric and go purely into hip extension- so possibly resisted hip and knee flexion could be a strong performance indicator, while also acknowledging the greater knee joint load of this strategy.

 

Foot Position

 

We encourage a neutral foot position.  If you are excessive internally rotated this will increase the susceptibility to knee abduction moments and having excessively rotated outwards can lead to pronation and lead to tibial rotation.

 

A big debate is if we heel strike or not?  I wouldn’t want to change direction just on the ball of my foot.  I assume I am going to increase the loading and susceptibility to ankle injuries and we need that firm base of support.

 

Optimal Technical Model

 

I don’t think it exists but we do need to acknowledge the Performance-Injury trade offs and address the technical deficits that aren’t going to offer any performance advantages.”

 

”@Alistair: I think that enhancing an athlete’s physical capacity is probably the most effective way to mitigate injury risks and develop their strength/power qualities to enhance performance.

 

Control to Chaos Continuum

 

I also like the Control to Chaos Continuum.  During a session I always start with pre-planned drills to begin with.  This allows you to make sure that you execute a certain volume of left and right change of directions, so you know how much work you did in the session, and it’s way of making sure you are getting the required dosage that you can build on.

 

 

Within more of an agility based drill you do forsake that element of control because it does become more chaotic.  But these are really important for game performance and this would be a good segway into the technical session.”

 

”Is COD testing losing its place in an applied setting?”

 

”@Tom:  I suppose it is, but I don’t think it should be.  I still think there is a time and place for it.

 

COD Testing

 

Pre-planned COD testing and training seems to be getting bashed at the moment as it’s not sport specific and it doesn’t involve perception-action coupling.  However, we test and train sprinting in a pre-planned environment.  Everyone is okay addressing sprint mechanics in a pre-planned environment, everyone is okay addressing jump mechanics in a pre-planned environment.  But as soon as we want to do a COD drill we immediately must throw a ball and a defender in, when in fact most athletes don’t warrant the right for that because they can’t MASTER THE MECHANICS in the pre-planned.

 

We don’t programme our plyometrics by going to a 50 cm box and thinking about an overhead target.  We do it in a controlled manner.  We still want those pre-planned elements in our training, we are not saying completely remove the unplanned elements, just think about the volumes and dosages.

 

I’d argue that in most sports our coaching philosophy is we want robust 360 degree athletes who are proficient at changing direction off left and right limbs from low, medium and high velocities

 

If we start breaking it down into our tests and we say we want our athlete to sidestep cut off 45 degrees, 90 degrees, do some aggressive pivots.  But then we also need to make sure they are equally proficient off both limbs.  So from a timing gate perspective, that means they need to do at least two trials on the left, two trials on the right, at 45, 90 and 180 degrees.  But that’s 5 metres, which shows that they are good at decelerating and changing direction from a low entry velocity.  So do I do repeat the same thing at a high entry velocity? Before you know it, we probably need 30 trials to build up this multi-directional speed profile and that’s just for one sidestep cutting action.

 

The other issue with timing gates is we are getting no insight into movement strategy, we are just getting an indication of how quickly they are getting from A to B (which is fine when the objective is in most sports is to get from A to B).  Particularly we want to know how are they entering, how are they changing direction and how are they exiting?  With the advancement of wearable non invasive technologies we are starting to get more insights into this.  We can mask our deficiencies in COD with superior acceleration and linear speed capabilities.

 

Change of Direction Angle Profile

 

We do Force (Load)-Velocity load profiling with our jump squats which takes 45 minutes so why can’t we do the same thing on the pitch and view this testing session as an isolated training session to elicit a training stimulus.

 

We can build a picture of 45 degree, a 90 degree and 180 cut for each isolated COD cutting task such as a sidestep cut.

 

Agility Assessments

 

I don’t think there will ever be a perfect agility assessment because sport is chaotic.  I am not a fan of one versus one testing, looking at how successful one is at evading an opponent.   I think it’s quite floored because we are still not getting an insight into perceptual-cognitive speed.  How do we standardise that defender for the attacker, how do we standardise the starting position? We can’t use a generic stimulus such as flashing light or arrow because they don’t differentiate skill level.  You need a sport specific stimulus and I don’t think you can complete that on the pitch.

 

To evaluate we should be looking at the movement quality and not just completion time or COD deficit, which are floored in my opinion.   We should be filming our athletes completing COD tasks to see how they are executing them – are seeing if they are adopting double foot contact or predominantly loading on one limb, and look at their trunk position etc (whether it’s during a testing session or during field based conditioning sessions).

 

The reason why I’m still a big advocate of these pre-planned tests is because we are focusing on that perception-action coupling (with agility drills).  What we are interested in is the mechanical ability to perform that task irrespective if we add some externally directed attention or agility stimulus.

 

If an athlete is poor at performing that task, it is only going to be amplified and worsened in an unplanned environment

 

I still think that a lot of athletes don’t really excel at these pre-planned tasks where we are evaluating the physical and mechanical ability to perform the COD task.

 

COD Deficit

 

The COD deficit is really popular as a way of getting an isolated measure of COD ability by subtracting a linear sprint time of equivalent distance from the COD test time such as the 5-0-5.

 

505 completion time – 10-meter sprint time

 

But it seems to be maybe potentially biased to slower athletes.  If you are ‘slower’ (but achieve the same 5-0-5 time) you’ll arguably going to have a ‘better’ COD deficit but the athlete is slower!

 

If you think of a test like a 5-0-5 a faster athlete is actually at a disadvantage because they have greater horizontal momentum and they are going to have to apply a greater braking force in order to decelerate and perform that task.  So something we have to factor in with the COD deficit is the athlete’s entry speed.

 

A better option might be to break the COD completion time down into three phases we can assess:

 

1. Entry time– point they enter COD to FFC
2. COD time – initial contact to toe off of main foot contact (FFC)
3. Exit time

 

 

If you’d like to read more about this, see Tom’s article on Simplifaster for more information.

 

Also pay attention to the pacing strategy (which might be indicated by entry time).  When you do a 5-0-5 you might see some athletes start decelerating prior to the entry gate (so they want to decelerate over 6 metres- 1 metre before the gate) which is a self regulatory effect where faster athletes potentially don’t want to utilize their full speed because of this braking load tolerance, and want to make the task easier.  It seems to be the same for weaker athletes as well.  It seems to be a physical capacity issue; eccentrically strong athletes can approach faster and decelerate quicker.”

 

 

Top 5 Take Away Points:

 

 

Science of Multi-Directional Speed

This blog is a review of the Pacey Performance Podcast Episode 380 – Alistair McBurnie & Tom Dos’Santos

 

 

Tom Dos’Santo

 

Tom is a lecturer at Manchester Metropolitan University, where he teaches strength conditioning and sports biomechanics. Previously, he’s worked at the University of Salford, and England Northwest and Manchester Thunder netball squads.

 

Twitter

 

🔊 Listen to the full episode here

 

Performance Perspective

 

Injury Risk

 

 

”@Tom:  As Alistair was stating before we can treat deceleration from a performance aspect from two perspectives; treating it as an isolated agility action. So if we consider Warren Young or Shepherd Young’s definition from 2006, a rapid whole body movement with a change of direction or velocity in response to stimulus. So deceleration in its own right is its own unique agility action, as Alistair was saying before.

 

Performance Perspective

 

We typically see it with our wingers potentially in rugby, American football, even soccer, doing those enforced decelerations from an attacking perspective to try and create that separation in order to maybe re-accelerate again or catch a ball or receive a pass.

 

Then from a change direction perspective, we’ve discussed something known as the kind of angle-velocity trade off. So typically as the angle increases, we need to reduce our horizontal momentum in order to perform that intended angle or change of direction. And typically, as angle increases our momentum muscle reduce and normally the ground contact time will increase in proportion to that angle.

 

Based on the biomechanical literature, it seems to be that in terms of the preliminary deceleration, there’s probably a minimal requirement to decelerate prior to, or for change of directions around about 45 degrees and below from a pre-planned perspective. Obviously there’ll be scenarios in multi-directional speed sports, where if you are having to perform a shallow change of direction where we only need to slam on the brake slightly for an acute angle change of direction, but typically in terms of the foot contact the second to last foot contact that we’re interested in (penultimate step), it seems to be 60 degrees and above, and we’ve even shown some evidence that even the anti-penultimate foot contact has a significant role in deceleration.

 

Figure- example of 180 degree cut

 

And again, some of the evidence seems to show that deceleration distances for these sharper change of directions can range from anywhere from about four to seven metres. So it highlights a multi-step nature of change of direction to reduce that momentum in order to deflect our center of mass.

 

So that’s key for performance. You’ve probably seen yourself as a practitioner athletes run too quickly and they can’t perform that intended angle of directional change, which probably affects their ability to deflect the centre of mass and makes them more susceptible to being tackled if it’s a invasion sport where we’re trying to evade our opponents. So it’s kind of like a speed accuracy trade off.

 

Injury Risk

 

Then from the injury risk perspective, deceleration actions are associated with injury inciting events. As Alistair has said before, we can get round about six times body weight of impact ground reaction forces within 50 milliseconds. So my background is ACL injuries. That seems to be the kind of window when these ACL injuries occur, these ACL injuries and other tissue injuries occur when we experience a mechanical load that exceeds its ultimate tensile strength.

 

So that could just be one single catastrophic load, the body’s load, and we can be referring to torques or knee moments in particular, which is just ground action force multiplied by the moment arm. So if you are landing stiffly and have a high impact ground reaction force, we’re potentially going to increase our knee joint loads and that could potentially increase load into the ACL and the other tissues and structures in the knee in particular. And over time if that single loads is high enough, that could result in a rupture, but as Alistair described really well before, potentially there’s this mechanism of a fatigue failure.

 

So we see athletes performing hundreds of decelerations, hundreds of change of directions without getting injured. So why is it that one time they do get injured? Is it because of a fatigue failure mechanism where we gradually get this reduction in structural integrity and the low tolerance of that tissue? If we experience chronic exposure to these sub maximal loads, which gradually weaken the knee ligament or the other tissues and without adequate rest and preparation, that sub maximal load now becomes a load that it can no longer tolerate, which therefore results potentially in a rupture or strain or whatever, the injury mechanism there is potentially there.

So they are associated with ACL injuries, other soft tissue injuries, ankle injuries in particular, if we experience some high inversion angular velocities, during decelerations. Jordan Mendiguchia, has been discussing this and another is JB Morin, if you’re talking about anterior pelvic tilt, and although knee injuries seem to be the predominant injuries associated with decels and change of directions, there’s also the potential to generate potentially some hamstring strain injuries as well. Particularly if we get rapid trunk flexion with an extended knee posture which we need when we’re decelerating.

 

And I think they’ve described it really well, particularly with an anterior pelvic tilt with this rapid trunk flexion, we’re going to get a lot of extreme lengthening and loading at the proximal portion of the hamstring. So in addition to knee injury risk from a knee ligament and a quadricep tendon and patellar tendon perspective, we’ve also got to be thinking on the posterior aspect and the proximal portion of our hamstrings as well.”

 

So with the importance of this based on what you’ve both said, let’s talk about monitoring and testing, so maybe come to you Tom, on testing, and then the monitoring side of thing day-to-day, come to you Alistair on that. Is that alright, Tom?

 

Testing

 

”@Tom: Yeah. So I suppose we’ll go from like bronze standard completely field based to the gold standard methods in terms of testing deceleration. So from a basic perspective, I think coaches need to start appreciating, maybe just using the coach’s eye and start evaluating the technical aspect in terms of deceleration and potentially using high speed cameras. We’ve all got smartphones. Generally, they all can record 120 frames per second or above. So there’s nothing to prevent us now from doing some enforced deceleration with athletes filming predominantly from the sagittal plane from the side and observing some of the technical characteristics.

 

Bronze Standard ?

 

If you have got the ability to observe in a frontal plane, we’ve experienced it before at Salford City, some of our players during just a simple linear deceleration task, will display high levels of knee valgus. So from a movement and quality perspective for every task, I know Kinogram is a very popular for acceleration. I think we should be doing the same deceleration from a movement quality perspective.

 

With the simple way of measuring deceleration, we need to be thinking about what the KPIs are, what are our key metrics that indicate an athlete who’s very successful and very competent at deceleration. So probably the key thing that we’re after is time to stop a deceleration or distance to stop. We want athletes to be able to brake very quickly over a short amount of time and over a short distance.

 

So one crude way of doing it is just simply with a tape measure. There have been some research studies that have used a tape measure. Now one way is to run and once they get to the cone and the tape measures, they slam on the brakes. Not the best way of doing it. A lot of athletes will probably adopt a kind of pace strategy or start decelerating prior.

 

The next step I’ll probably recommend is probably again using high speed cameras.  There’s probably two ways of assessing deceleration, which Damien Harper speaks about and I think Phil Graham Smith has done before.  We have decelerating to a predefined point. So maybe that’s 15 or 20 metres, or you sprint to a certain distance and once you reach that marker, then you slam on the brakes. So Damien Harper’s a big advocate for that one. Phil Graham Smith has done the former where you actually decelerate to a predetermined point.

 

So what we could do with our cameras, we could position the camera probably about five to 10 metres away in the sagittal plane from the marker. And what Damien Harper did is he examined the approach velocity from 19 to 20 metres just before they had to slam on the brakes and then using your cameras, you can identify a tracking marker potentially on the pelvis or use the whole body if you wanted to. And then you would measure the distance it’s taken them to decelerate from that marker, past that point. And you could work out the time to stop. So we get a distance to stop and a time to stop.

 

But what we need to factor in is the athlete’s approach velocity as well, because it’s going to be bias towards lower momentum athletes. If you are a larger momentum athlete so heavier and faster, you’re at a disadvantage, because you’re going to require greater braking or net, horizontal braking impulse to decelerate and reduce your momentum.

 

The issue with those tasks is that it does require 2D analysis. So it can be a bit more time consuming and based on some of Damien Harper’s or Phil and Paul Jones’s research, athletes tend to start decelerating before that 20 metre mark. So they were reporting deceleration distances of three to four meters, when in fact they actually started decelerating potentially one to three metres before that point. So that’s something that we need to bear in mind if you are just measuring distance to stop from that predefined point.

 

Silver Standard ?

 

Probably the next step or the best way to go is potentially using like a radar or a laser device. So we have Stalker speed guns. So that’s what Damien Harper’s used. That samples at 47 Hertz, so we get an instantaneous velocity profile for our athletes. I know Paul Jones or Phil Graham Smith have used LabX which I think sample at 100 Hertz, so we get a bit more data. With deceleration we’re interested in meters per second squared and some people are interested in peak deceleration values. However, that only represents one data point and that could just be a freak or random part of data.

 

 

So I know Damien’s a big advocate of measuring average deceleration drawing the deceleration task and he started breaking it down into early and late deceleration. And the beauty with that device is we’re able to identify when they’ve started decelerating. So even if you are putting that 20 metre checkpoint, you can identify if they’re decelerating, maybe two to three metres earlier. And that’s what Damien Harper seems to be finding. Maybe around about the 17 and a half metre marker point, they seem to be putting on the brakes, which is fine as long as you are monitoring. He identifies deceleration distance as the distance from when they’ve achieved peak velocity to going towards that back pedal. So zero meters per second, and then in a negative direction.

 

So we can get those metrics from that. And in terms of the potential metrics that we want to examine, we can get our deceleration distance.  They seem to be our two KPIs that we’re interested in. So getting the distance to stop and time to stop with appreciation of that athlete’s entry velocity. So I don’t think it’s one single metric, we have discussed a possibility of maybe creating a ratio. So take the athlete’s initial entry velocity, and then maybe looking at the ratio of that entry velocity or peak speed and their distance and time to stop.

 

I believe the Ergo Test is another device that’s around about 5,000-10,000 Euros. Stalker speed gun is a bit more affordable, about $2,500 and LabX, I think a bit more difficult to hold of. I believe companies such as Playermaker, which is wearable for the foot, are working on the device potentially to start monitoring it in the field. And then the unique aspect of that is we’ll start to be able to monitor foot to foot and load distribution between left and right limbs to see if there’s any asymmetries.

 

LED React, another company are using radar and they’re creating kind of like a 25 metre radius dome, and they’re potentially working on a deceleration test using that same similar bit of technology.

 

Gold Standard ?

 

Probably the gold standard, but probably very difficult to implement in a field would be 3D motion analysis where we can get that instantaneous assessment of centre of mass velocity, but that requires Qualisys or Vicon, very difficult to implement in the field. Although there are now the advancements in marker-less technology as well and I know Jonas Dodoo has started using Binary sports app where identify the marker, and then they automatically track them. Not too sure on the validity of that approach.

 

But again, a bit more insight into not only just a kind of the instantaneous velocity, but we’ll get a bit more insight into how they’re performing the deceleration, so you can get some insights into some of the spatial temporal characteristics, limb velocities, step length, step frequencies, etc. So that’s a really good, I think there’s a lot of potential there. And I think over the next three to five years, I think marker-less technology will be amazing and probably bridging the gap, getting more insights to practitioners in the field.”

 

From a day-to-day monitoring point of view, Alistair, when it comes to deceleration, what kind of things are you doing? Is it like deceleration count? Is it deceleration intensity using player tracking etc?

 

Monitoring

 

”@Alistair: I think Tom’s alluded to a lot of potential technologies down the line are going to be very useful and give us a lot more insights to assessing and monitoring these actions. But I think based on current technologies (and I think pretty much every top club are using them now) is usually through GPS tracking. It is obviously very useful and it tells you a lot of information in relation to  the volume and also the intensity of whole body movements.

 

I’d like to underline that it is just whole body movement and for us to really understand what’s going on in terms of what is the actual movement strategy of the athlete, we currently won’t get that. We’re able to more deeply analyze supposed centre of mass velocity with these units. But I think even that will take a lot of extra work within the day-to-day practices. So like you said, we’re using count currently. I think it’s over three meters per second squared where we are classifying them as high intensity actions. And that’s the same for accelerations as well.

 

I’d like to highlight that there are differences between the demands of a high intensity acceleration versus a high intensity deceleration, which currently just use the same arbitrary cut off value, whether it’s three metres per second or 2.5 metres per second or whatever. But in actual fact the actual maximum rates of deceleration are much higher than acceleration. We also know about the biomechanical requirements of decelerations versus accelerations being very different. There may be a bit more of a metabolic cost to accelerations versus greater biomechanical loading of decelerations.

 

So I think we probably need to look into it a little bit more to see how we’re actually evaluating the different actions instead of using these arbitrary thresholds. I know that there’s been recent work, I think Damien was involved again to do with individualizing a high intensity locomotive profile using both acceleration and deceleration, but also your max aerobic speed and max velocity. And I think they’re the key things really going forwards because if we move away from horizontal decelerations just for a second, high speed running at the moment, we’re all using this arbitrary cut off, whether it’s 19.8 kilometres an hour or 20 kilometres per hour to assign the absolute volume of running that they’re doing at that intensity.

 

I think if we really want to individualize it, you want to be using that max aerobic speed versus the maximum sprint speed and getting that anaerobic speed reserve. And I think the same can be said for horizontal decelerations as well. So unfortunately I don’t have the answers to what potentially can be the next movement for the centre of mass velocity elements but I think realistically, we want to be getting the inter-limb differences, which these more foot based accelerometer technologies are going to be offering just to get a bit more insight into what are the asymmetrical loading patterns between limbs.

 

And obviously there’s going to be position elements to that position specific elements to that and just more simply individual elements to that. You know, some players might prefer to use or have a dominant leg to turn off or to decelerate off. And if we’re able to monitor that at both the acute chronic level, we will be able to uncover the trends in relation to if one specific limb is getting overloaded versus another one potentially getting under-loaded? So is there going to be spikes in workload between the limbs in that sense?

 

So I think until we have these technologies validated and more use in research going forwards, we’re at a point where we’re going to have to make do with what we’ve got currently. And I mean, there’s still valuable insights to be made from GPS.

 

And I think if we’re to focus on horizontal deceleration as a key performance indicator within a weekly micro cycle, we’re looking at it from these two acquisition days. So on a day-to-day; we’re looking at two acquisition days, maybe potentially being a G -4 and a G -3, that being the days before a game, as these are windows of opportunity to  train horizontal decelerations.  From a monitoring perspective, you might get that using just simply counts of horizontal decelerations, you can get an indication as to the volume that has been carried out in a training session, whether that is through athletic development training or the sport specific practice through manipulation of drill parameters.

 

You could maybe see typically on an intensive day where the pitch areas are a bit smaller and you’ll see a larger volume of accelerations and deceleration and change of directions being performed. And then that will give us an indication of the volume of deceleration work that these players have been exposed to during training day or this intensive theme day. And I think that is more your volume element and I think Damien Harper discusses this kind of deceleration endurance aspect if we’re looking at it from a more physical rationale.

 

However, then I’d also highlight that in a typically more, what we call extensive training theme where you open up the pitch areas and typically, this is where you get the exposures to maximum velocity, and there’s higher volumes of high speed running, which is obviously a key training theme within the week. If you’ve got one match at the end of the weekend and on these extensive training days, we’re going for that high intensity movement speed. But you’d probably also see these high intensity decelerations be performed there. So with the greater distances that you typically get in from opening up the pitch areas, this enables higher movement speeds, which require more intense braking to slow the athletes down.

 

So I think if we’re looking at volume on an intensive training day and looking at the volume of high intensity deceleration actions on a more of a extensive training focus day, you might want to look at the intensity of the high intensity deceleration. And I know Tom’s criticized that potentially maximal deceleration doesn’t tell you a great deal because it can actually be just an erroneous movement action. And obviously the kind of unit error involved in that as well from a technology sampling rate perspective, it’s difficult to uncover. But maybe it’s just a way of informing are we actually exposing our athletes to high intensity or very high intensity deceleration actions that potentially offers a bit of insight, and opportunity to track that over time to see when our athletes, when our players have been exposed to above 90 to 95% of their maximum sprinting speed. And if they’ve not done that in the last few weeks, that’s something that we need to sit down and go, right, we need these players to be exposed to that stimulus.

 

And I think the same can be true for horizontal decelerations. I think if a player’s not being exposed to maximal intensity decelerations, it’s something that we need to sit down and go, right, well, we need to make sure that we’re preparing these athletes because this is going to be happening in competition.

 

I think currently based on the technologies that we have available to us at the moment, talking more about these whole body measures of exercise volume and intensity with GPS tracking, I think they’re probably our best bets to give us insights into the volume and intensity of actions. And there’s obviously frequency and density and all that kind of thing that needs to go on as well. But I think moving forwards, we really want to have a bit more insight into the interim differences between what potential deceleration loading is occurring which these kind of accelerometers like Playmaker or the IMUs and maybe give us a bit more insights into all the spatial temporal factors, such as ground contact times, stride rate, stride frequency.

 

We don’t actually know what athletes are exposed to during competition and training. Hopefully we can end up using these technologies in a bit more of our day to day practice to actually uncover the trends on an individual basis to see what is normal for an athlete and go, right, okay. So this player performs a significant amount of turns or deceleration on their left limb. Why is that? Is that a positional requirement? But then to go, is that normal for them? And actually, you know, they might turn a lot more off their left limb and they might actually have a lot more loading going on through their left limb. Just trying to find a bandwidth of what is normal, what is a spike, what is an under-loading to inform more individualized training strategies or interventions as a consequence of that monitoring.”

 

 

Top 5 Take Away Points:

 

 

Science of Multi-Directional Speed

This blog is a review of the Pacey Performance Podcast Episode 373 – Jeremy Sheppard & Dana Agar-Newman

 

Dana Agar-Newman

Dana is a senior practitioner at the Canadian Sport Institute Pacific, and a head strength conditioning coordinator at the University of Victoria.  He has also worked in rowing and rugby, including with the Canadian women’s rugby sevens team at Rio 2016.

Twitter

 

? Listen to the full episode with Jeremy & Dana here

”Thinking about how we’re testing jumping is more important now than ever as technology is expanding rapidly.  There are a number of tools out there that can give you a number for jump height but it may not actually be how high that athlete has truly jumped- their centre of mass, it may not even be a valid number.  So it’s really important to know how jump height is being calculated with the tool that we choose.

 

Even if we are using something like a force plate our choice of software can also impact whether we go with one company or another.

 

Flight time Method

 

• My Jump – iPhone App – through frame rate of your camera
• Opto jump
• Jump matt

 

Another tool is something like a Vertec, and now a lot of us are using force plates using single or multiple force plates so you measure asymmetries and that uses the impulse-momentum method.  That;s important to know because all those tools give us a slightly different measure, so you’ll jump higher using the flight time method often than you will using the impulse-momentum method using the force plates.  The reason why is because the flight time method assumes you take off and land in the exact same position when in actual fact most athletes are going to land with a slight flexion of the hips and knees, and slight dorsi flexion in the ankle so it will inflate the jump heights slightly.

 

 

Each tool has advantages and also cons.”

 

Measure What Matters

 

When it comes to identifying the metrics we want to analyse how does that conversation differ between sports?

 

@Dana: ”You should always take your testing and try and compare it to the KPIs or your sport because there are so many metrics that come out of a force plate; I think in our script right now there are 90 metrics maybe even more, but you should really be trying to narrow those down because a lot of those metrics may be telling you the same story and a lot of them may not actually be that reliable.

 

So start with that, and then with the metrics that are reliable then you want to be comparing them to the key actions and KPIs within the game, so when this metric moves, that metric moves in the game as well.

 

You can look at different levels of athlete, that would be your basic level of analysis, so are these metrics different in lower level athletes compared to say higher level athletes.  Then you could look at a regression approach where you are predicting performance on the y axis and the force plate metric on the x axis; if the force place metric moves I know that I can expect to see a certain movement in this performance metric.  And probably a more advanced way of doing it is to look at the individual level so you’re saying with this individual athlete, when this metric moves I expect to see this metric to move over here in this KPI.”

 

@Jeremy: ”Take volleyball for example, there are some sports where the KPI is the outcome of the jump, and the outcome of the jump is how high you jump.  That’s really important not to forget, and the variables we look at can help us to differentiate individualised training but there may be variables within a jump or even a something like a style of jump or a context that never or rarely occurs in the sport but it has a relationship to a component, and that component relates to the KPI skill.

 

 

So if I think of the spike jump in volleyball, where you have an approach, well you might say there is no depth jump involved.  But what we found, and what we have repeatedly found over and over again, is that depth jump performance is related to your ability to attenuate those forces in your approach and convert from horizontal to vertical.

 

If you’re looking at measuring the spike jump performance in context there is so much noise, but if you take a depth jump that’s very repeatable, and that depth jump relates to that transition ability of horizontal to vertical.  So the influence of the depth jump and its unique way of developing or in this case testing the stretch shortening cycle relates to your ability to take those steps and then transition in the penultimate step to convert into a vertical displacement.  It’s not cause and effect but it has a high influence on that.  So then you connect those dots to the actual performance.”

 

@Dana: ”there is a big push to make testing super super sport specific, but we already have a sport specific test and that’s watching the game!  The question really comes well why is this athlete not able to jump as high as possible above the blocker (to use Jeremy volleyball example).  You need to take the test and make it more general.  Another example would be a lot of these aerobic tests that have become super sport specific.  Well if the athlete tests poorly on it, well was it because they had a poor vVO2, poor change of direction ability, their anaerobic speed reserve wasn’t that big?  You’ll still left with the question, what was the limiting factor with this athlete, and there is a place for making the test more general.”

 

Are there any considerations for individualising training for youths versus seniors or males versus females etc?

 

Youth vs Adults

 

@Jeremy: ”You need to learn your context, which is not a quick fix if you are new to the sport.  You might do your neuromuscular profiling but with children you might identify some really great things to do but I’m still not going to do them because of a myriad of other reasons, because of their biological ability to tolerate that load, because they might be growing fast, and because we want to be here for a good time and a long time, so you might subordinate the ”correct thing” muscularly in the hierarchy of training needs because they have so much gain to make elsewhere.

 

The analogy I make with this, is similar to nutritional supplementation – I do not like to buy nutritional supplements for athletes who cannot drive past a McDonalds because what’s the point? You have to earn the right to be in the penthouse suite and you have to have a foundation.  So that 15 year old might need a lot of other things first, and it’s not that the cool neuromuscular stuff is not important, but they are getting a lot of jump volume from playing the sport, and maybe I don’t want to add to it until their movement is better, their knowledge of recovery and regeneration is better.  If I keep adding highly individualised neuromuscular training just because I can, and my ego says that that makes me feel better at the end of the day, I may be creating a false economy and a false message.   So what me measure matters as it communicates to our athletes what we think is important.

 

You train a dog, you coach people.  So it’s about the bigger picture of education.

 

Men and Women

 

One of the challenges is if you have a sport where they depth and participation is really low it can actually be difficult to make well intended differentiation between men and women.  Whereas a sport like volleyball is wonderful because the participation is high and the depth is tremendous.  And so I find myself looking at trends in stature and strength levels and looking at ”people who present this way, rather than men who and women who,” as the top level of men and women because the participation in both sexes is really high.

 

@Dana: ”As athletes move up in sport, the top level can be quite homogenous, so a variable that could separate high and low level performers may no longer separate elite performers and the metric you look at maybe slightly different depending on your population.

 

The analogy I like to give is that if you’re going to a dance to find your life partner, the metric you need that $15 to get your ticket to the dance.  But once you get into that dance, your dancing skill begin to matter.  Can you dance?  So money matters initially, but later on it’s something else, can you dance?  It’s the same thing with testing athletes.  Certain things may be important when testing low level athletes, and may no longer separate the population with higher level athletes.”

 

I’d love to get some insights and your process you go through when choosing exercises for jump training?

 

@Dana: ”In diving the youngest divers I get in the weight room are 12/13 years old and the oldest diver at the Toyko Olympic games is 27 years old.  So a very different thought Initially it is all about teaching them a wide variety of movements in the gym, teaching them to land properly and teaching those skills and maximising training days.  With the higher level athlete it comes down to the assessment driving the exercise selection.

 

• Loaded Jump profile – squat jump
• Isometric mid-thigh pull (IMTP)
• Counter movement jump (CMJ)
• Depth jump profile

 

From those tests there I’ll choose my variety of exercises along with a conversation with the coach to see what they are seeing technically.  So there are some things that are really hard to measure if you get stuck using that single tool.  It gives you nice easy numbers to interpret but I think its really important to go back and observe that athlete qualitatively [performing their skill].

 

 

Initially I was really big in doing the Force-Velocity (F-V) profile with my higher level athletes and training off the F-V profile.  I was finding results exactly you find in the research, where everyone’s jump heights improved initially, but after a while, once they are optimal (and the divers got to optimal really quickly because they were doing a tonne of jumping every day and training consistent in the weight room).  So what I ended up doing is biasing them to more Force dominant in the off-season and then I would try to shift them to optimal (doing more velocity work) and sharpen the knife leading into competition.  What I found is that if I was trying to keep them at optimal I wasn’t moving the needle at all.

 

The Depth Jump Profile

 

If you find that you need to work on the more elasticity and stretch tolerance of the athlete something I would also recommend is to jump off a series of increasing heights and the key thing to note is that athletes should be experienced at depth jumps.  If they are, what you will find is that athlete’s jump height will continue to increase as they drop from increasing height up until a certain point and then it will start decreasing again.

 

So the question myself and Jeremy discuss often is, should we train at the optimal height where they jump highest or are we better to train slightly at the deflection point where they are starting to come down again?

 

For me in the off-season I will train at the deflection point and then leading into season I’ll train at the optimal where they are jumping the highest.  I don’t have any research to back that up but it seems to be working.

 

@Jeremy: ”I’ll do jumps above that deflection point and some times much higher but they just land- because landing is so critical to snowboarding.  I’ll also do jumps below optimal but it’s a different style/skill, where I don’t instruct them to jump as high as possible.  Having them do these lower heights where the point is not necessarily to optimise the impulse, it’s to basically get off the ground as quickly as possible, so it’s a different style and when I write that in the programme its a drop jump, not a depth jump.

 

Is programming for a sport that has one big jump different from a sport where you have to jump hundreds of times a game?

 

@Dana: ”I think that comes down to conditioning.  You need to train what you do, so you need to increase your capacity of movements, as well as how high you can jump, and both of those things are important.  In a sport like volleyball to build that repeatedly I probably wouldn’t be doing that much stuff at body weight, I’d probably doing a few things to stimulate qualities such as doing heavier and lighter than bodyweight as they are already doing so much jumping at bodyweight.  I’d probably also be looking to implement a few worse case scenarios in training, and looking if they are already getting that in the training.  If they are then I wouldn’t be doing that outside of the training session in the weight room.  But if for certain athletes who aren’t getting enough game time to stimulate those physical qualities you may need to pull it out to a more general setting to stimulate certain qualities.  So you have to look at what they are getting out of the sport and then fill in the pieces.

 

@Jeremy: ”What happens when you working in a sport like Volleyball where there is so much jumping you’re going to have the good fortune of meeting a freak, who has an extraordinary physical quality or skill and in volleyball that shows up often because you’re testing jumping all the time.  Your outlier in the vertical jump can often be your least well rounded strength trained athlete.  In the gym setting and any other strength assessments you do, they are not the impressive one and they are often one of the ones you are most concerned about and don’t test well.

 

Where that will manifest is that they will have the largest drop in their jump sustainability in say their 1st set to their 5th set, or over the course of a tournament.  Now you could argue that that’s okay because even at the end of the match or the tournament they are still jumping better than other people, but it still leaves clues what you’re looking at.

 

Leave your ego at home thinking you’re going to part of a project to take a 100 cm vertical jumper and take his vertical jump and make it 105 cm because really the work that is punching you in the face, is if someone is dropping that much over the course or a match or tournament, that opens up a big window of probability of injury because they are playing until tremendous fatigue and literally speaking they cannot handle the rigours of the sport.

 

And if they are this alpha that is a major athletic quality on the team then the success of the team is related to their ability to stay in the match, and so the work might actually be the boring stuff, and the actual job to be done is movement quality and making them neuromuscularly stronger that’s going to make each landing less fatigue inducing.  So you don’t change the game but the game is now relatively less fatiguing for the athlete.  So what you have to put your ego around is the fact that you’re going to make your 5th set performance much better!

 

@Dana: ”In terms of landing during jump assessments, how the athlete lands can influence the metrics you are seeing.  For example, if you absorb the force over a greater time you are going to find lower peak force and that comes down to impulse (which is Force x time) which is essentially your change in momentum.  But absorbing force over greater time may not be applicable depending on the sport you may be working with, and so you may have to absorb that force quicker so there will be a higher peak force to get that same area under the curve.   So the jump strategy should be sport dependent and the strategy will influence what metrics you are doing to look at.”

 

 

Top 5 Take Away Points:

 

This blog is a review of the Pacey Performance Podcast Episode 361 – John Wagle

”The benefits of eccentric to me really comes down to the fact the force production isn’t constrained by the lengthening velocity.  We can produce really high forces at really high speeds, which happens to occur quite often in sport.  That pairs pretty well with how we need to adequately prepare athletes for the demands of sport.

 

A lot of the tangible benefits are with longer term applications of eccentric training in programme design:

 

• Fast fibre cross sectional area changes
• More explosive performance
• Longer fascicles
• More sarcomeres in series
• Stronger anabolic signals
• Stiffer muscle tendon units

 

Chronic Adaptations to Eccentric Training: A Systematic Review

 

 

 

”On the shortening velocity side that’s where the sarcomeres in series come into play for performance, and from the injury risk side we are getting longer fascicles as well, so something like the Nordic leg curl is very well supported in the literature especially when you do add eccentric overload, and it really seems to have an influence on muscle architectural changes within the muscle.

 

 

You have stronger anabolic signalling with eccentric training and more satellite cell activation which in theory is going to get you some more muscle size change at the fibre specific level rather than whole muscle, and then more voluntary agonist activation and down regulation of any inhibitory response of the nervous system.   That’s not to say because of that list I should only focus on eccentric training as it’s only a piece of the puzzle but I do think it’s an under appreciated programming variable especially with its versatility.”

 

With all its benefits why would coaches not take this on board, and implement some of it into their training programme?

 

”Some of it is on the athlete safety side with the supra-maximal eccentric loading, and that all gets bucketed into eccentric training, although eccentric training does not necessarily have to be supra-maximal, but I do think there is a stigma that this a very stressful stimulus, and it is, like even in the sub-maximal versions of it, there is certainly some physiological stress associated with this that doesn’t necessarily appear with other training methods.  But I do think there is a way to programme in it, with the acknowledged apprehension because of the potential implications of recovery status of their athletes.

 

People point very readily to the repeated bout effect and that’s certainly something that we need to consider, but you are still going to be disruptive to the recovery status of the athlete if you are progressing and providing adequate overload and variation regardless of what you are doing with the eccentric training side so the repeated bout affect doesn’t absolve us from considering the stress induced from eccentric training.

 

The repeated bout effect refers to the adaptation whereby a single bout of eccentric exercise protects against muscle damage from subsequent eccentric bouts. … There is some evidence to suggest that the repeated bout effect is associated with a shift toward greater recruitment of slow twitch motor units

 

For anyone who hasn’t introduced eccentric focused training before, where would you start and what would you recommend for people to progress through?”

 

”Level zero for me would be the tempo or movement cadence manipulation with eccentric training.  There is actually not a tonne of support for it, especially in terms of strength and power adaptations which is pretty logical if I slow the eccentric phase down I’m not going to be able to use as much weight, and that intensity down shift has implications for strength and power changes.

 

 

There has certainly been some studies that have shown muscle size changes but my interpretation of literature is that I have yet to be convinced that slowing down the eccentric phase is superior to regular ol resistance training without a targeted approach to movement cadence.  But that being said, I do think there is a lot to be gained to revisit technique and make sure that those things are really sound and to make sure you are stressing tissues the way that you intend.

 

I like flywheel as the next logical progression.

 

 

There is a little bit of elongation, let’s call it, between the eccentric and concentric phase when you have to overcome the inertia at the bottom of a squat for example, where it can give people time to produce a lot of force but they are not necessarily ready to produce that force rapidly, so the flywheel lends itself well next, plus there is a little bit more [research] support on the hypertrophy side, and especially for the lesser trained athlete so you’ll also see some strength, power, and change of direction changes as well.

 

Then you get into things like accentuated eccentric loading (AEL) and you might progress into that from sub-maximal to supra-maximal and things of that nature, and because of the higher eccentric rate of force development (eRFD) most notably, that lends itself really well to progress to plyometrics and top speed sprinting, which are kind of the tail end of what you would want to expose that athlete to in terms of the highest level of eccentric stress.  Whether you want to bucket plyometrics into eccentric training is up to your interpretation, but to me that’s kind of the end of the road, and AEL does a good job of setting you up for some of those more advanced plyometrics.

 

1. Tempo training
2. Flywheel training
3. AEL
4. Plyometrics and sprinting

 

All that being said, I think it’s important too that it’s more about the blend of these methods, that you’re not going to do one of these methods in isolation, and you would do elements of each no matter what stage of training you are in, and that’s important to be able to set you up for success in progression.”

 

How can people progress their use of flywheel to then progress onto AEL?

 

”Flywheel has a longer transition between the eccentric and concentric phase, to give them more time to produce force.  There is also an element here where the athlete can control the intensity.  A lot of the eccentric overload present in flywheel training is mediated by the concentric velocity.  So although there is an element of progressive overload in absolute terms with the size of the wheel, a big chunk of that is mediated by the athlete.  So you have a bit more versatility to meet the athlete where they are at, and progress them accordingly.

 

Accentuated eccentric loading (AEL) prescribes eccentric load magnitude in excess of the concentric prescription using movements that require coupled eccentric and concentric actions, with minimal interruption to natural mechanics.

 

 

 

1.  Eccentric load is in excess of the concentric load– doesn’t need to be supra-maximal, which automatically makes it different from tempo training where you have the same load on the way down and the way up, and makes it distinct from flywheel training where you have the same inertial load on the way down and way up.
2.  A coupled eccentric and concentric action– which makes it distinctive from negatives (eccentric only training).
3.  Minimal interruption to the natural mechanics of the selected exercise– which further differentiates it from flywheel training, a lot of times you are wearing a harness, and if anyone has ever been on the flywheel device, it’s a great training tool so this isn’t a criticism, if you squat on a flywheel it’s different than if you squat with a barbell in terms of the mechanics which will stress tissue differently.

 

To do this you can use manual resistance from a partner (push ups and nordics etc), weight releasers, hold dumbbells especially as it applies to plyometrics.”

 

 

What are the specific benefits of AEL outside of what we have spoken about with eccentric training?

 

”There does tend to be an acute testosterone and growth hormone response that persists a little bit longer than with traditional loading, and possibly some alterations in glycolytic enzyme production and lactate clearance ability with AEL which could have some advantages for sports that have a large endurance component (soccer, 400m runnner).  AEL was typically reserved for strength/power type athletes but that may not be the case with that new research that while it is pretty thinly supported in the research it is intriguing enough to continue to explore.”

 

Can lower end athletes benefit from some of the AEL methods?

 

”In terms of loading and the stimulus you are providing, there is not really a barrier to entry besides obviously you have to consider eccentric training is pretty stressful so they are probably going to take a little bit longer to get through the recovery process from that training.

 

I think too if you are looking to apply AEL for potentiation you have a much narrower window to operate with to actually induce that potentiation.  You are walking a tight rope between fatigue and potentiation, and those weaker or less trained athletes, that tight rope is just going to be much thinner.  So those that are stronger probably have a little bit more margin for error on programme selection.

 

 

I thought for sure with the mechanistic underpinnings there would be a potentiating effect with AEL, such as the muscle is in a greater active state, more calcium sensitivity etc, but it’s actually a really mixed bag [in the research] especially when it’s narrowed to resistance training such as bench press or squatting with weight releasers, there’s just as much research that shows that it is detrimental as it is beneficial to that acute performance, and there appears to be a pretty big sensitivity in programme design and load structure.

 

Plyos vs. Resistance Training (Short-term acute effect)

 

So if you were going to do it, and to make sure you are not burying the athlete, it would be best to do it alongside some sort of augmented feedback such as a velocity measurement or a between set counter movement jump.  But on the plyometrics side, it is still a little bit of a mixed bag, but there seems to be a little bit more clarity in terms of what is going to work and what isn’t going to work.  The studies that do have a favourable acute effect from AEL tend to be ones that have a conservative loading (holding a pair of 10kg dumbbells and also plyometrics that have a lesser centre of mass displacement (AEL doesn’t tend to work with a really large displacement like a deep squat which causes a fatigue effect).  But a tight coupling, the rapid eccentric action with an eccentric overload does appear to be where you can induce some potentiation.

 

I would tend to put my more stressful content at the beginning of the week so I can provide my athletes with the recovery at the back end of the week. So for me AEL to me fits better at the beginning of the week particularly in season, so for players that have a high speed running demand especially upright top speed type running, having an AEL exposure early in the week to expose them to some higher eccentric rate of force developments but not necessarily what they are going to encounter in sprinting.  And then have a top speed exposure later in the week, where it is an emphasis in their training, acknowledging that if they are training in their sport in between they will still do some high speed work between those sessions as part of their sports practices.

 

A nice progression could be:

 

1. AEL counter movement jump (with dumbbell release at bottom)
2. Depth jump (shock method)
3. AEL depth jump (with dumbbell release at bottom)
4. Repeat serial hurdle jumps

 

Where does this fit into the bigger programme?

 

”With AEL specifically I do feel it fits very neatly at the tail end of a cycle where you do have a demand to develop some maximal strength or retain the maximal strength you have already developed but stage some of those higher power output or higher velocity efforts, where you are trying run your fastest, jump your highest, be at your best, kind of staging a taper, would be where I would put AEL, in terms of what it can retain and what it can expose the athlete to in terms of high eccentric RFD.

 

If you are going to follow AEL with a taper you are okay with the intentional high stress nature of that eccentric training, so if you are going to pull training content away to promote that recovery AEL fits really well as part of a over reach to stage taper, or the block prior to set that taper up.”

 

 

Top 5 Take Away Points: