BMI-dependent effect of running on joints

[Titanium]

This study found that runners with BMI < 22 benefited, but heavier runners showed increased risk of osteoarthritis and hip replacement.

The article postulates that in heavier runners the wear-and-tear outpaces any increase in cartilage production from the running stimulus.

Apparently cartilage can regrow under proper stimulus. That could be a good thing for healing of lifting-related injuries and even to offset age-related decline.

http://www.ergo-log.com/running-redu...arthritis.html

[Mark Rippetoe]

Cartilage can in fact regenerate. For those sufficiently interested: http://www.amazon.com/Skeletal-Funct...=Dennis+Carter

I cannot address the statistical analysis used in the paper, but there seem to be some problems. And I'd be interested to know what they mean by "other exercise."

[hollismb]

I'm going to stay away from the study itself, but this is one of those articles that's going to get somebody's mom spouting off that running is bad for your knees and hips unless you're really skinny because of something they read in Prevention magazine.

Age was the biggest risk factor that Williams uncovered. With every year the risk of developing osteoarthritis and needing a hip replacement increases by five to six percent.

So, they admit that age was the primary factor/difference, but BMI is somehow the upshot of the article?

When Walker divided up the runners and walkers according the number of kcals they burned daily, he noticed that the runners had less chance of osteoarthritis or a hip replacement the more calories they burned.

Does not a larger person, running for the same amount of time, burn more calories than a smaller person?

One factor that did increase the risk of damage to joints was bodyweight. The higher the runners' and walkers' BMI, the greater the risk. The stimulatory effect of running on cartilage production is apparently greater than that of wear and tear in lightweight people.

If your BMI is higher than 22-23 then this reasoning doesn't apply to you. In this case frequent running is not good for your joints.

Well, I better get to work on losing some weight then. At a height of 6'2", for running to stop being 'not good' for my joints, I need to be less than 171 pounds.

Who's cartilage is taking more of a beating while running? A bounding skinny guy with a BMI under 22, who's a heel-striker with a cadence of 165 steps-per-minute, or a shuffling chubby guy with a BMI over 23, running with a forefoot strike with and a cadence of 180 spm?

[JM3]

I'm going to stay away from the study itself, but this is one of those articles that's going to get somebody's mom spouting off that running is bad for your knees and hips unless you're really skinny because of something they read in Prevention magazine. ?

Forwarding this to my mom.