Is Lifting Weights Safe For Children?
Nervous to Lift Weights With Children? In this post I give my Top Tips on Lifting Weights With Children and unpack some myths about the safety of using resistance with youth athletes.
If you’re a coach and you are looking for more info on ‘How To Get Buy In That Lifting Weights Is Safe For Children, I have FREE Webinar on the topic, be sure to click on the link to register for this FREE Training
To be clear, I am in favour of children lifting weights. But I will explain below by what I mean by this statement so please read the whole article in order to ensure you correctly understand my position.
Background to This Post
Okay, so first things first, this is not the first and it certainly won’t be the last time I write about this. There are some myths that just won’t go away, and the myth that lifting weights with youths is DANGEROUS is one of them.
The inspiration for this post was that one of my colleagues was asked by a parent to NOT lift weights with their child (for context the child was a teenager going through puberty). I find that this is the time when this conversation is going to typically come up.
Usually the ‘child’ has gone through a skill learning phase of how to lift weights, meaning lots of bodyweight, broomstick and ‘light bars.’ (the photo below is of a youth using bumper plates and a light bar, meaning it looks heavy but it actually totals less than 20kg in total).
All of this goes by unnoticed (or at least not commented on by the parent). Then at some point the coach thinks… ”now is time to swap the training bar (let’s call this 10kg) for an Olympic bar (20kg)…and the parent immediately gets on the phone. For context, in my experience, the child is usually going through puberty (12-14 yrs old), will be at least 50 kg in body mass and has probably had at least 6 months training history. So a 20kg bar represents less than 50% body mass. So we invariably get into a discussion about what we define as ‘lifting weights,’ and what the perceived dangers are. For some reason the sight of the Olympic bar is usually the trigger for a conversation.
Myths of Lifting Weights
Now I must be clear, you won’t have this conversation with a parent (or I’d be extremely surprised) if their child is attending a weightlifting club, with the goal of competing as a competitive weightlifter. They understand that lifting weights from a young age is going to be part of the process of preparing to be elite in that sport. It’s more likely to be when the child is participating in another sport and as a coach you use the techniques of weight training or weightlifting in your programme.
Usually the argument goes something like this…’I don’t want my child to lift weights because…..
- I’m worried it will stunt their growth
- I’m worried it will cause damage to their growth plates
Now most of the reading I have done in this area has focused on the stress lifting weights may place on the articulations of the knee joint (especially with loaded deep squatting). A good article to read is Growth Plate Fractures which I will refer to later on. For an overview of the Maturation of the Growing Spine please click on this link Spinal Development paper. But for the people who don’t want to read all 31 pages here is the summary:
- Primary ossification takes place at 1-3 years and 4-6 years.
- Secondary ossification appears between 10-13 years (puberty) and fuse 18-25 years old.
Parents know that when a child is fully grown, the growth plates harden into solid bone.
Many parents are also aware that stress fractures in the spine of the posterior arch (pars interarticularis) are associated with repetitive flexion/extension (in my main sport of Tennis stress fractures of the spine are known to be associated with repetitive characteristics of the serve action). So there is already a bit of nervousness about adding ‘high’ levels of additional stress to the developing (and therefore weaker) spine with high level weighted squats.
Medical Definition of OssificationOssification: The process of creating bone, that is of transforming cartilage (or fibrous tissue) into bone. … Bone is osseous tissue. “Os” is a synonym for “bone.” The Latin word “os” means “bone” as does the related Greek word “osteon.”
So it could be argued that while a child is still growing particular care should be taken, and that when the spine reaches adulthood it will be less susceptible to damage, and this is the time that ‘higher’ levels of loading could be used.
So let’s look at this in a bit further detail……does lifting weights at a young age stunt growth or damage growth plates? What do we mean by ‘taking particular care?’ And finally what constitutes ‘higher’ levels of loading?
Growth Plate Fractures- Any Truth?
Take from Growth Plate Fractures (see full article):
The bones of children and adults share many of the same risks for injury. But because they are still growing, a child’s bones are also subject to a unique injury called a growth plate fracture. Growth plates are areas of cartilage located near the ends of bones. Because they are the last portion of a child’s bones to harden (ossify), growth plates are particularly vulnerable to fracture.
Approximately 15% to 30% of all childhood fractures are growth plate fractures.
Most growth plate fractures occur in the long bones of the fingers. They are also common in the outer bone of the forearm (radius) and lower bones of the leg (the tibia and fibula).
Cause
Growth plate fractures are often caused by a single event, such as a fall or car accident. They can also occur gradually as a result of repetitive stress on the bone, which may occur when a child overtrains in a sports activity.
All children who are still growing are at risk for growth plate injuries, but there are certain factors that may make them more likely to occur:
- Growth plate fractures occur twice as often in boys as in girls, because girls finish growing earlier than boys.
- One-third of all growth plate fractures occur during participation in competitive sports such as football, basketball, or gymnastics.
- About 20% of all growth plate fractures occur during participation in recreational activities such as biking, sledding, skiing, or skateboarding.
- The incidence of growth plate fractures peaks in adolescence.
Daz comment: To be honest the statistics here are inconclusive. We can say that over 50% of growth plates are associated with participation in recreational or competitive sport. For those who choose to believe that lifting weights is unsafe, it would be easy to assume that this surely contributes towards some of the other 47%.
But other statistics suggest the contrary (Hamill, 1994):
- Further evidence of the safety of weight training relative to other sports and exercise activities can be seen in the injury rates of other youth sports (Hamill, 1994). Weight training’s injury rate of 0.0012 injuries per 100 participant hours pales to the 6.2 injuries per 100 participant hours in youth soccer and 1.02 injuries per 100 participant hours in basketball. Time in the weight room carries even less risk of injury than a traditional physical education class where there is an injury rate of 0.18 injuries per 100 participant hours.
In cases of injuries reported in the scientific literature the overwhelming majority of these injuries were attributed to improper technique in the execution of the exercises and excessive loading
One-year study of a USA Weightlifting Regional Development Center program that included more than 70 pediatric athletes in which no reports of injury were noted (Pierce, 1999).
Training programs in which training loads are prescribed and monitored and in which training activities are supervised have proven to be remarkably safe in terms of the frequency of injury occurrence.
To my knowledge there are:
- No studies in science that have shown that deep squatting cause meniscus and cartilage on the backside of the patella to wear away.
- If this were true we would expect to see extreme amounts of arthritis in knees of weight lifters. This is not the case
- No studies in science that have reported an injury to the growth plate of a child during weight training when proper supervision and technique instructions are provided
How Can We Take Particular Care During Periods of Accelerated Growth?
In my experience the aspects of athletic training that expose the athlete to the highest stresses are those that lie outside of the gym. The stress of repetitive loading of the sports skill itself places far higher stresses on the body than anything I will expose the body to in the gym.
So any intervention to manage the stress on the growing body needs to start with a review of overall training stress starting with a possible reduction of the amount of hours of time spent playing the sport.
Landing forces are several times bodyweight whenever an athlete jumps and lands or sprints and decelerates to a stop. Furthermore the repetitive high speed, ballistic actions of kicking and striking place significantly more stress on the body. Yet parents and coaches see these as necessary endeavours that you must pay the price for entry into the world of elite sport.
Whenever I have spoken to parents there is simply a lack of understanding of the nature of Force acting on the body during high speed movements on the sports field. Because they are only using their body weight they just assume the forces must be lower than when you go into the gym and lift with something on your back. But performing a drop jump like in the photo below can cause up to five times bodyweight load through the spine. This compares to less than one time bodyweight that a coach will typically ask an athlete to experience in the gym- and the movement is performed under control so it is even better tolerated!!
If you are a parent or coach and are interested in the physics of the forces acting on the body I’d encourage you to watch my FREE Webinar
Now one thing we can definitely do, from the weight training stand point is eliminate spinal loading and move from bilateral (both legs) back squatting, to unilateral (one leg) squatting. This removes the need to do spinal loading while still continuing to apply an overload to the legs. This is a no brainer and can relieve some of the parent’s concerns about lifting excess weight through the spine. We might not have as much control over the forces they experience playing sport, but at least we are using alternative (but equally effective) ways to overload the legs.
Please see my article on this: Which is Better- Back squat or Split Squat?
What Constitutes High Loading?
At APA I have a performance pathway for all aspects of athleticism including strength. These are known as Key Performance Indicators (KPIs). Now if your sport is competitive powerlifting or competitive weightlifting then these KPIs are an end unto themselves. Whereas if you play another sport like tennis, they are simply a means to an end, not an end unto themselves.
However, while a tennis player is never going to need to be as strong as a competitive weightlifter it is generally seen that most adult elite sportsmen and women are capable of lifting several times their body weight in a back squat (2 x bodyweight), deadlift (2.5 x bodyweight) or isometric mid thigh pull (4x bodyweight).
Now to reverse engineer this at APA we have a six stage performance pathway: I will use the back squat as an example, as it is often used as a reference for lower body strength.
- Basic 1– bodyweight (early childhood)
- Basic 2– soft resistance (bands, balls and light bars-pre-adolescence)
- Basic 3– intro to more external load (50% bodyweight for 10-15 reps- adolescence)
- Advanced 1– maximal intent to lift for 5 reps (100% bodyweight- post puberty)
- Advanced 2– maximal intent to lift for 3 reps (150% bodyweight- junior pro)
- Advanced 3– maximal intent to lift for 1 rep (200% bodyweight-senior pro)
So for me, I am very comfortable lifting 50% of an adolescent’s body weight for 10-15 repetitions provided they have excellent technique and can lift and lower the bar at the controlled tempos demanded of them.
However, as I stated earlier it is common sense that if a child is going through some accelerated growth we can substitute some of the back squats for split squats or one leg squats and so on.
Position Statements
If you’re still not convinced or would like to read further I encourage you to read the following:
- Youth- USA PositionStatementNSCA2009
- Youth- UK Lloyd_Positionstatementonyouthresistancetraining_BJSM_2013
Hope you have found this article useful.
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