Even perspiration can be a factor, Bemben says: "Cyclists may lose a lot of calcium in their sweat," she says. "Even if they're taking in amounts [of liquid] that are seemingly high for the average man, that might not be enough to balance what they're excreting."
Getting the word out
Though the subject of bone density occasionally pops up on cycling message boards, it's not exactly a hot topic. "Some people have no clue," Testa says. "They don't even know it's an issue." A dual energy X-ray absorptiometry (DXA) scan is most often used to test bone density, a non-invasive test that uses low levels of radiation. Testa adds, "Often people are surprised to find that their results are not ideal."
And though women are reminded (via the media or their physicians) to up their calcium intake to prevent osteoporosis, men usually don't get the same messages. Young male cyclists, especially, figure they're healthy and don't need to be concerned. Some sports medicine physicians, orthopedists and cycling coaches discuss the issue with patients, but Testa and others say more education may be necessary.
Coggan, still a competitive amateur cyclist, got another DXA scan a few weeks ago and the news wasn't great -- he has osteopenia in his lumbar spine and osteoporosis in his hips. He says that while he does do weight training and runs occasionally, he knows he needs to focus his athletics more on health rather than performance. "I have a couple more athletic goals I want to achieve," he says, "and then I may have to start jumping rope."