Should Kids do Strength Training?
“It is easier to build strong children than to repair broken adults”
- Frederick Douglass
The notion that kids should not strength train is a common misconception among the general public. The rationale behind this attitude is that strength training for kids damages growing bones and potentially stunts growth; which is rooted in the notion that strength training is an inherently dangerous activity. However, this attitude has largely shifted in the scientific community in response to new research demonstrating not only the safety of lifting weights, but also the numerous positive outcomes associated with strength training!
What is strength training?
Before diving into the topic of strength training for kids, it is necessary to define what strength training actually is! As a working definition, strength training is defined as physical conditioning in which muscles contract against resistance with the goal of increasing muscular fitness. Under this definition, goals such as increasing muscular power, coordination, strength, and hypertrophy are all considered strength training. As such, the modalities utilized will be specific to the individual, aligning with their current physiological development, maturity, and goals.
What does the science say?
Under appropriate conditions, strength training is perfectly suitable and extremely beneficial for kids. With assistance from and under the supervision of a professional, children and preadolescents can improve not only their strength but also their bone density, balance, lipid profiles, fat-free mass, and coordination through structured training. While concern for the growth of children's bones is warranted, there is minimal evidence supporting the claim that strength training hinders growth in any appreciable way. What is more commonly purported is the strengthening of the bones through the increased bone mineral density that accompanies proper strength training. In essence, strength training for kids provides many of the same benefits as adults. However, in kids, the benefits of coordination, balance, and gross motor movement pattern improvements are largely amplified due to the plasticity of their growing physiology.
An analogy I like to use is to think about the human body as a block of clay. Fresh clay is easily molded and shaped into whatever you want, provided the maker has the skill and means to manipulate it to its design. However, if you let the clay sit for an extended period of time and then try to shape it as you wish, you will run into more difficulty as it becomes a bit stiffer. With the addition of some water, you can regain some pliability of the material, but it will not be the same as when it was fresh. If you let the clay sit too long and completely dry out, then you will have even more difficulty shaping it, and will require some ingenuity and perhaps other techniques to attempt to shape it.
When learning movement patterns and coordination, the human body operates in a similar fashion. When we are young, our bodies are able to learn movement patterns more quickly because our nervous system is primed to adapt to the demands imposed upon it. As we get older, if we have not learned certain skills it becomes much more difficult to do so as our nervous system and muscles have spent years learning other patterns; more or less, our bodies “forget” how to do things, making the learning process more challenging. Essentially, kids need to learn fundamental movement patterns such as squatting, running, hinging, and twisting to set them up for lifelong movement success.
Aside from the physiological benefits gained from proper strength training, an often overlooked benefit of strength training for young persons is in the psychosocial realm. By adhering to proper strength training protocols, young persons can gain improved self-confidence and body image. Seeing the physiological changes from strength training and receiving the positive endorphin releases that accompany strength training are just a couple of factors that facilitate postive psychological outcomes. The positive reinforcement from the physiological and psychological benefits also lays the foundation for a lifelong journey of health and wellness. In a modern North American society that is in the midst of an obesity epidemic, strength training at a young age builds the habits, behaviours, skills, and discipline to adopt a healthy lifestyle across the lifespan; thus laying the groundwork to prevent future health complications through improved health markers and decreasing the risk of various non-communicable diseases.
So when should kids start?
Now that the benefits of strength training are clear, when can people start? While current scientific literature has debunked the notion that kids cannot do strength training, obviously it is not appropriate for newborn babies to start training! While it largely depends on the physical and psychological maturity of the individual, most healthy children can begin intentionally strength training around the time they are 7-8 years old as long as it is under proper supervision. Researchers such as Faigenbaum indicate this age as a general guideline because most children around 7 years old have the maturity to listen and follow instructions. Some kids may be ready sooner, some later, but as another general guideline: if your child is ready for sports, they are ready for strength training!
Summary and Practical Application
In summary, kids are generally able to strength train when they are mature enough to follow instructions and listen to form cues, which is usually around 7-8 years old. By starting early, we build a solid foundation of physical literacy and build habits that support a healthy lifestyle across the lifespan. In application, strength training for kids will look drastically different than it will for adults. In general, we want to minimize axial or spinal loading and stay away from maximal effort training modalities. Most strength training for kids will be lower volume, include a variety of movements in multiple planes of motion, and consist of low external load or calisthenics-based exercise. In the care of a professional that understands the importance of physical literacy, kids can experience major benefits from strength training!
References
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