THE ARTICLE
A number of interesting studies published in the last couple of years have raised the possibility that cyclists may have more brittle bones than other athletes. What is already known is that the incidence of broken bones among elite cyclists is high. In 2009, Lance Armstrong broke his collarbone. Christian Vande Velde, another Tour de France leader, fractured six of his bones during a race in the Giro d’Italia in May of last year.
You might reasonably expect that broken bones would occur when travelling 65 miles an hour and crashing into the pavement. However, bikers seem to have worse and more frequent breaks, and low bone density may play a role. Aaron Smathers, a biker himself and a researcher at the Department of Health and Exercise Science at the University of Oklahoma, says, “If you have low bone mineral mass, you can wind up with a much more serious break from a crash” than if your bones are thicker. His study used bone scans to evaluate the bone density of 32 competitive male cyclists as compared to age-matched controls. The scans revealed that most of the bikers had lower bone density in the spine than the control group, and some even had osteopenia, a condition that is a precursor to osteoporosis. Smathers notes, “To find guys in their twenties with osteopenia was surprising and pretty disturbing.”
Another study with similar results was published last year in the Journal of Bone Mineral Research. This study followed competitive cyclists aged 27 to 44 during an entire race season in the state of Colorado. Bone scans showed that they began the season with slightly lower than average bone density, and that by the end of the season they had lost a substantial percentage of their bone density in their hips. They had not lost bone density in their spines. At a follow up exam three months later, they had recovered a small portion of bone mass in their hips.
Cycling seems to have a unique impact on the bodies of athletes. Usually, we think of endurance sports as beneficial to skeletal health. A March 2009 study published in the Journal of Strength Conditioning and Research compared the bone densities of runners, weight lifters, and cyclists. The researchers found that the cyclists had the lowest bone density of the three. Another study revealed that triathletes actually increased their bone density moderately during a season.
The main reason cyclists seem to have this problem is that cycling is not a weight-bearing activity, like running or weight lifting, therefore it causes little impact on the skeleton. Weight bearing activities are good for the bones and actually are known to increase bone density and overall bone strength. Interestingly, body mass seems to play a role, since the lightest cyclists have the lowest bone density. Since competitive cyclists often burn more kilojoules than they consume each day, the energy deficit may contribute to bone loss. In addition, calcium is lost through sweat, and cyclists can lose hundreds of milligrams per hour of calcium during rides. A study from 2004 that evaluated cyclists given either calcium-enriched water or tap water showed that those drinking tap water had higher markers of bone loss than those who drank the calcium-enriched water. Calcium supplements and calcium-enriched water may help prevent some of the bone loss associated with long, hot rides.
Despite all the research data, the average cyclist needn’t worry about his or her bones. The data found in these studies was specifically derived from high-level, competitive cyclists. Smathers says, “The studies to date have looked primarily at racers. That’s a very specialised demographic. These guys train for hours at a very high intensity. They sweat a lot. They never go for runs. They don’t usually do much weight-lifting.” He believes that weight training might go a long way towards staving off bone loss in competitive riders. If you are cycling a great deal, particularly in the heat, and are concerned about the state of your bones, you can have a bone scan done for peace of mind. Otherwise, continue to cycle and enjoy, and a bit of cross-training is never a bad idea.
YOUR FEEDBACK
Have you got any comments about this article? In an effort to provide an unbiased site for our visitors, we ask that you provide your opinion!
