Does lifting weights inhibit growth for teens and kids? Some people I know argue yes, while others argue no. So, I want to know which one is true.
TL; DR: No, they won't impact growth if practiced within reason, and there is no damage to growth plates from injury.
The medical community and the public in general seems to regard strength training as a general voodoo practice that will "hurt you". Fortunately, this has been getting debunked soundly for over a decade now.
Despite earlier concerns regarding the safety and efficacy of youth strength training, current public health objectives now aim to increase the number of boys and girls age 6 and older who regularly participate in physical activities that enhance and maintain muscular fitness.
The American Academy of Pediatrics recommends strength training for children 8 and up.
Children will tend to play sports much earlier than they can strength train. Those sports and basic calisthenics teach motor control, discipline, and physical prowess. This will provide a great base if you move into supplemental strength training as they become older and can pay attention to training and form elements. In any case, as long as the exercise is age appropriate (Such as don't have your 10 year old squatting 250) and supervised, there shouldn't be an impact.
From there, you have kids who are:
- Used to spending focused time on physical training.
- Used to moving their bodies.
- Used to drills/skills: activities that are not sports themselves, but necessary for helping sports.
Also consider the following two study excerpts:
Experimental training protocols with weights and resistance machines and with supervision and low instructor/participant ratios are relatively safe and do not negatively impact growth and maturation of pre- and early pubertal youth.
Numerous studies have demonstrated that with appropriate supervision and precautions, resistance training can be safe and effective for children and adolescents.
[Resistance training had] no detrimental effect on linear growth.
With all of that, there is the possibility that pushing children in exercise programs without paying attention to rest and nutrition needs could possibly result in growth impairment due to overly high stress levels or malnutrition. However, the basic question of does lifting affect height, the answer is no and it is even recommended.
This was brought together from two excellent answers on the Fitness Stack Exchange site, with thanks to Daniel and to Eric Kaufman.