The Tour de France Begins: Are the Cyclist's Bones Ready?

The Tour de France begins this weekend and while all eyes are on the return of seven-time winner, Lance Armstrong, some scientists are more interested in the bone health of professional cyclists over the month-long bicycle race.

Over the past several years, research on bone health, has uncovered some surprising information regarding the effect of cycling on bone strength. And it's not all good.

Several studies, including one last year, found lower bone density in elite level cyclists who train for hours on the bicycle.

Researchers are not entirely sure the cause of the bone loss in cyclists, but the current theories include:

• The nonweight-bearing nature of cycling.
• Minerals, including calcium, are lost at an enormous rate during hours of sweating.
• An energy imbalance (more calories are used than consumed) over hours of exercise.

Low bone density, referred to as osteopenia, can lead to osteoporosis and a significant risk of bone injury. A fractured clavicle, like the one Lance Armstrong suffered in March, is one of the most common fractures to occur in cyclists.

In order to combat these risks, all athletes are advised to participate in some form of regular weight-bearing exercise, such as:

• Weight Training, especially the the Squat Exercise
• Plyometrics
• Jumping Exercises, such as practicing the vertical jump.
• Body Weight Exercises can also help build bone density
• Jump roping, or running