Is there any point to these kinds of exercises to employ bone remodelling and Wolff's Law?

Question

For those of you who can't or aren't inclined to watch the video, it is a presentation by a martial arts instructor who shows various exercises you can do with a wooden rod. He basically hits himself lightly on various parts of his body. The idea is that this will cause bone remodeling, which will improve bone density to the parts of the body that he applies the exercises to. I'm guessing this is related to martial arts practices where, as I understand it, students practice kicking at trees and punching planks of wood in order to develop "toughness".

Is there any point to these kinds of exercises? Are they practical and beneficial? Is there a particular program that is reputable for knowing how often and in what manner these kinds of exercises can be trained for?

My aim is to determine whether these kinds of "contact exercises" could do me some good, beyond the lame calisthenic exercises that I resort to these days. I'm 31, 225 lbs, 6' 1", and wouldn't mind some added bone density, especially as I age. Right now going to the gym isn't a realistic possibility.

Here's the video: https://www.youtube.com/watch?v=OIh7CenPIu4

Answer 1

What you're addressing is also known as cortical remodeling.

The human body is constantly recycling bone, at the rate of about 10% replacement per year. Impact and load bearing sports (Soccer, martial arts, weightlifting, running, etc.) are known to help retain bone mass density (BMD), while non weight bearing sports (swimming, cycling) do not have the same benefits. This BMD benefit was shown to persist through adult/aging cycles, even if the person no longer participated in athletics past youth levels.

Much of the benefits from cortical remodeling due to sports comes from the stresses placed on the bone from the muscles (through the tendons) that are attached to them. I am not aware of (and was unable to find any through pubmed) any published articles that directly relate impact to bone growth in the area, although there have been some measurements that show elbow regions with greater bone density due to repeated elbow strikes, but whether this is due to the impact or the stress on the tendons/muscles was not shown.

The whacking of the leg, thrusting hands into sand, hitting the boards (makiwara) are not necessarily designed to increase the bone density, but to increase the muscular strength to direct impact and to deaden the sensation of pain in the area.

Especially for younger athletes, this is not recommended. Direct impact in a small area (such as hitting the shin into a tree) can kill the periosteum, which will result in no more bone growth in the area. If you feel the shin of an athlete who played soccer for example, you will often find "pits" in the edge of the bone where growth was impacted.

For the vast, vast majority of people that train in martial arts, there is no real need to start mangling your shins or beating up innocent trees. When we did not have protective padding, it was necessary to deaden yourself to impact to be able to fight effectively, however this is not really the case any more unless you are intending to fight competitively in the Muay Thai/kickboxing/MMA type arenas.

Answer 2

Hitting yourself lightly with a stick might be a good way to start if you're not very good at handling pain. But to adequately add bone density you should be aiming to eventually (emphasis on eventually) be hitting a hard surface with about 10% of the required force to fracture the bone you're training. If you ever wanted to do tiger style Kung-Fu for instance you would need strong fingers and the tips of the bone would have to be strong, dense and desensitized from pain. Shaolin monks would literally poke tree's.

I would start punching some newspapers taped to your wall, and slowly take the newspapers away as the months go by. Eventually you can punch hard surfaces without problems. You will have rounded off knuckles and have a tough body.
It's not only good for martial arts but for general injury prevention. As you age you lose bone density, but if you already have a high bone density you won't be fragile when you're old.

Try adding jump up knuckle push-ups to your bodyweight exercise routine. At your weight that should be an adequate impact on your knuckles to start with.