Staying fuelled while cycling helps bone density


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I’m not sure if my headline is misleading. There’s a new press release from the University of Missouri titled “Maintaining Energy Balance During Stage Races May Protect Cyclists’ Bones, MU Researcher Says,” but the description of the research is a little confusing (and the journal paper in Applied Physiology, Nutrition and Metabolism has yet to appear).

The new study is by Pam Hinton, who I interviewed last year for a piece on exercise and bone density. That previous study compared running, cycling and weightlifting, and concluded that running was good because of the jarring impacts, weightlifting was good because the added muscle puts stress on bones, but cycling had neither of those benefits.

The new study monitored cyclists during the Tour of Sutherland, a six-day, 10-stage race:

Hinton found significant increases in markers of bone formation and bone breakdown among the athletes whose energy intake matched their energy expenditure throughout the race.

Fortunately, bone formation increased more than bone breakdown, which suggests that everything is fine for those who take in enough calories.

“The findings suggest that participation in stage races might not have negative effects on bone turnover if energy intake matches the energy cost of high-intensity racing over several days,” said Pam Hinton, associate professor in the Department of Nutrition and Exercise Physiology. “The results are consistent with the practical recommendation that elite cyclists should match their energy intake to the high energy demands of stage racing.”

What’s unclear from the press release is whether she actually observed enhanced rates of breakdown in cyclists who weren’t getting enough calories during the race. If so, you’d think they’d mention it. If not, then I’m not sure how the study proves anything about adequate energy intake (though it’s obviously a good idea with or without this study!). I’ll follow up on this when I see the full study.

Anyway, uncertainty aside, the message seems to be: hauling ass during a brutal multi-day stage race won’t have any negative effect on your bones, assuming you’re taking in enough calories.