One of my YouTube subscribers asked me a curious question - does weightlifting affect your height? He also referred to a video of one YouTube expert who claimed not only that weightlifting affect your growth, but also that doing pullups can increase your growth. Quite a claim, eh? I think it's totally worth a deeper look.
How do we grow?
I think it's important to start with the basics by looking into the bone growth process. Our bones have certain areas where certain type of bone cells proliferate (reproduce) and mature. These cells create a collagen matrix - a meshwork of connective tissue fibers, which in turn gets filled with minerals like calcium and others. The resulting bone structure reminds reinforced concrete and is quite durable. These growth areas (also called growth plates or epiphyseal plates) are active throughout the first quarter of our life and are responsible for the growth of our skeleton until puberty and during the growth spurts happening around that time. One important point I'd like to make that these growth plates close after the age of 15-16 in girls and 17-18 in boys, so effectively any heavy resistance training that is happening afterwards cannot affect our growth. As everything in nature there is a certain variability in the timing of growth spurts and closure of these growth plates, so some individuals might have them functioning at slightly later stages of life, but this is negligible in general.
Resistance training and growth plates
Now, we can talk about really young athletes whose growth plates are still functioning and they are still growing. Can physical exercise affect them? There are two aspects to it:
1. Potential damage to the growth plates. I can see how theoretically we can damage these growth areas, but we are evolutionarily programmed to be active, to hunt, to fight and wrestle and effectively these areas developed in such a way that it's quite difficult to damage them – it would take an actual injury, a fracture to change the course of their development. Such injuries are very rare and usually are a result of improper form and unsupervised training. There is an amazing review of multiple aspects of resistance exercise in young athletes by Faigenbaum & Myer, 20101
2. Hormonal response to resistance exercise - as we engage in heavy lifting, especially, in major compound movements, our bodies react with increased levels of testosterone and growth hormone. Both of these hormones stimulate the growth plates and should effectively result in overall height increase, not decrease (again, given that there are no injuries)
Can pullups increase your height?
That's another claim and I think that now we are ready to address it fully. As discussed earlier, if your growth plates have closed, there is no way your height will increase. If you are doing any compound movement, which includes pullups (these are amazing), before the closure of the growth plates, the hormonal response to these exercises will likely result in height increase over time. Important point here is that it doesn't have to be pullups, it can be any kind of resistance exercise as the hormonal response is systemic, not local.
So, these are my thoughts and I would like to thank my subscriber for these amazing questions and for drawing my attention to them. I hope it was helpful and, as always, feel free to ask questions, to make comments and to explore my website and to subscribe to my YouTube channel for updates.
Sincerely Yours,
Dr.Sam
Video: Inspirational Q&A #4 Can Weightlifting affect you Height?
References:
1. Faigenbaum AD, Myer GD. Resistance training among young athletes: safety, efficacy and injury prevention effects. British journal of sports medicine. 2010;44(1):56-63.