Can Lifting Weights Stunt Growth? The Truth About Kids + Strength Training

There are many excellent physical and mental health benefits of lifting weights. 

For example, weight lifting increases strength, builds lean body mass, increases bone density, burns calories, boosts metabolic rate, decreases blood pressure, reduces body fat, and can lower stress.

But is lifting weights safe for kids? Can lifting weights stunt growth?

In this article, we will look at what the evidence says about whether lifting weights can stunt growth in children and advice and best practices for strength training for kids.

We will cover: 

• Can Lifting Weights Stunt Growth?

• Why Do People Say Lifting Weights Stunts Growth?

• Benefits of Strength Training for Kids and Adolescents

• How Old Should Kids Be to Lift Weights?

• Tips for Strength Training for Kids

Let’s dive in! 

Can Lifting Weights Stunt Growth? 

Parents of children and adolescents often ask, “Does lifting weights stunt growth?”

The good news is that provided your child is using the proper form and an appropriate resistance load, lifting weights should not stunt growth even during childhood.

Indeed, most health experts agree that it is simply a myth that lifting weights will stunt growth during maturation; this fear is not substantiated by any scientific evidence.

Instead, there is plenty of research demonstrating the benefits of strength training for kids, provided the program is supervised and appropriate for the child’s age and ability level.

These benefits include: improving muscular strength, increasing bone density, decreasing fracture risk, improving strength-to-size ratio, increasing self-esteem and mood, increasing balance and core control, and increasing coordination and flexibility.

Evidence suggests that some amount of exercise is actually required to stimulate the epiphyseal growth plates, so being physically inactive may potentially adversely impact eventual height.

Additionally, research has shown that exercise can support skeletal growth because it helps facilitate the necessary hormonal milieu to promote statural growth.

For example, physical activity stimulates the secretion of human growth hormone (HGH) and other anabolic hormones, which in turn increase the growth of bones, muscles, and other tissues.

Exercise also seems to help direct metabolism towards using fats and cellular energy for growth rather than other potential uses.

With all that said, although a healthy amount of exercise may support growth, your adult height is primarily determined by genetics, with studies suggesting that up to 60 to 81% of your height is attributable to your genetics.

Another factor that can affect your height is your nutritional intake during childhood and puberty. 

For example, malnutrition, inadequate caloric intake, low protein intake, and insufficient calcium, vitamin D, phosphorus, and magnesium anywhere from infancy through to the end of puberty can compromise your weight gain and potentially stunt your growth.

For that reason, while lifting weights during childhood or adolescence won’t directly stunt growth, it’s important that strength training workouts are performed in the context of adequate caloric and nutrient intake during growth.

Your child or teenager should be consuming enough calories, protein, fat, carbohydrates, vitamins, and essential minerals to support their physical activity and weight-lifting workouts, so that statural growth isn’t compromised by using up necessary energy for growth.

There is some evidence to suggest that excessive exercise may temporarily block statural growth by competing for energy/nutrients required for growth.

Furthermore, while catch-up growth can occur, depending on the timing and degree of the energy deficit, growth retardation may be permanent.

All this is to say, provided a child is not doing an extreme amount of strength training, lifting weights should not stunt growth, and exercise, in general, encourages normal, healthy bone growth.

Again, it’s also worth restating that the majority of eventual height is determined by genetics.

Why Do People Say Lifting Weights Stunts Growth?

The primary reason why people ask the question: does lifting weights stunt growth for children is due to the concern about how lifting weights may impact the growth plates.

The growth plates are regions of cartilaginous tissue at the end of the long bones, such as the femur in the thigh, the tibia in the shin, and the humerus in the arm.

During development, these cartilaginous zones are soft and spongy and are sites of statural growth. Eventually, the growth plates close and harden into mature bone once growth has ceased at the end of puberty.

The only real danger to the growth plates in terms of exercise-stunted growth is that of growth plate fractures.

Approximately 15 to 30 percent of all childhood fractures involve the growth plates.

With that said, there is no evidence to suggest that the risk of fractures involving the growth plate are any higher lifting weight than playing other sports, and the risk may actually be lower due to the no-contact nature of strength training and its ability to improve neuromuscular control and coordination.

Furthermore, loading the growth plates with strength training exercises, whether body weight or with external resistance, can actually help stimulate growth.

Benefits of Strength Training for Kids and Adolescents 

One of the benefits of lifting weights during development is that it really improves neuromuscular feedback and coordination, which is one of the reasons it can reduce the risk of sports injuries in youth.

Not only are the tissues stronger, but a child or teenager who lifts weights can have better proprioception and kinesthetic awareness, as well as neuromuscular firing patterns for safe movements.

According to a large research review, strength training during childhood and adolescence can be an effective form of Integrative Neuromuscular Training (INT).

INT is a style of fitness training that integrates general and specific strength and conditioning activities in a way that has been shown to not only improve physical fitness and performance but also reduce the risk of sports-related injuries in children. 

Other studies have also concluded that one of the benefits of strength training for kids and adolescents is that it can help reduce the risk of injuries and help kids develop “physical literacy” to offset the consequences of a sedentary lifestyle. 

Moreover, studies suggest that physical activity habits, or lack thereof, tend to persist into adulthood, so starting strength training during childhood or adolescence can promote lifelong exercise.

How Old Should Kids Be to Lift Weights?

Kids can start strength training as soon as they are old enough and ready to participate in sports. 

Because physical, cognitive, and emotional maturation occur at different rates for different children, there isn’t a hard-and-fast rule as to when kids can start strength training. However, it’s important to distinguish strength training and lifting weights in the context of youth.

Young kids can safely perform strength training exercises that require only their body weight, such as squats, push-ups, frog jumps, bunny hops, dips, bear crawls, crab walks, planks, etc. 

These types of muscle-strengthening exercises are excellent for children of all ages and safe for very young kids as well. Plus, they helped develop neuromuscular coordination and strength for common everyday and athletic movement patterns.

A child should have fully mastered the basic foundational movement patterns of a squat, bench press, deadlift, etc., before any type of weight is added to the exercise.

Additionally, in most cases, it is best to stick with resistance bands if your child wants to increase the difficulty of strength training exercises before the age of 7 to 8 or so.

Light weights can then be used, depending on your child’s strength, coordination, and technique, along with cognitive and emotional readiness.

Your child should also be fully capable of properly following instructions before they start lifting weights or engaging in any sort of formalized strength training program.

Tips for Strength Training for Kids

Here are a few best practices and tips for lifting weights for kids:

• Start with bodyweight only: Work on the foundational movement patterns rather than lifting heavier weights.

• Fuel well: Make sure the child or teenager is eating enough calories and consuming a well-balanced, nutritious diet. Also, make sure that they refuel with a healthy, protein-rich snack after strength training.

• Get coaching: Proper technique and a well-designed program are imperative to safety.

• Assess readiness: Maturation is a sliding scale, and a child may be physically ready to lift weights but not cognitively or emotionally ready to do it safely yet, or the converse may be true. All three areas of development must be aligned and ready.

• Keep it fun: Exercise should be a form of play.

Developing a habit and love for exercise at a young age is a massive benefit for all children. If you are looking for some fun games your children and their friends can play, take a look at our PE games for kids!