Actually the best test for this, would be to take 100 people, 25 who cycle, 25 who run, 25 who do walking (including hiking, and other walking based exercises), and 25 who do couch surf. Then compare the bone density numbers. My guess is that highest bone density would be the runners, next would be the walkers, close behind or even to the walkers would be cyclists, and far behind both would be the couch surfers. The real question, is, what is the median bone density for the average person, in a certain age group, do other factors affect this, such as diet, sex, weight and general fitness level?
Originally Posted by damnable
A cyclist has a much lower muscle mass then a power lifter, but actually has a higher muscle mass then a couch potato, is this a similar thing, it's not that cyclists have lower bone density then average, but that runners have higher bone density then average.