My chiropractor showed me an article that he had seen in the LA Times recently about the unusually high amount of cyclists that suffer from lowered bone density. In the article they talked about riders in their late 20’s and early 30’s who were coming in for hip fractures from wrecks that were not that bad.
They also talked about the high amount of cyclists that are suffering from low bone density. The problem is that cycling may be great for your heart and lungs but since it is a non-load bearing exercise the bones do not get stressed. Without being stressed the bones will actually get weaker over time. Hips and low back seem to be the areas most affected by loss of bone density in cyclists.
Now, the story did focus on road cyclists and road cycling is not nearly as physical as mountain biking but the warning is still valid for us. Cycling is great but you need to do load bearing exercise as well to keep your whole body healthy. Guess what the best way to avoid and reverse bone loss is?
Strength training! So, not only will it make you faster it will keep you from breaking a hip when you trip over something. Seriously, how “fit” can you be if you can pedal all day but you can break a hip?