A:Running gets most of the flak for grinding down joints and stressing bones. But just when you thought those fluid cycling motions kept you safe… A new study says that cyclists doing extreme distances “could be causing irreversible damage to their bones.”
Here’s what you need to know: If you've been mixing up your rides with other forms of exercise, you probably have nothing to worry about. But as healthy as biking is, it's not necessarily good for your bones. Serious cyclists training for extreme distances may be at risk for fractures and, eventually, osteoporosis, especially if they're also restricting their calories.
"The main concern is for people who have mainly cycled and done very little weight-bearing activity, as this is what stimulates bone growth," says Peter Brubaker, executive director of the Healthy Exercise and Lifestyle Programs at Wake Forest University. Weight lifting is, unsurprisingly, the most beneficial kind of weight-bearing activity. It’s something you should work into your routine if you need to balance out a pedaling-heavy regimen.
Other on-your-feet activities are options too, though they’re not perfect. Brubaker's previous research indicates that approximately 50 percent of collegiate cross-country runners have abnormally low bone-density levels. Other endurance sports, such as cycling and swimming, may put athletes at an even greater risk, he says, because they don't even get the lower-extremity weight-bearing benefits of running.
Cycling, specifically, is a risky sport because competitive athletes also tend to monitor their weight and diet so strictly. This can create nutritional or caloric deficiencies that can also contribute to bone loss. Cyclists who are underweight are at the highest risk of bone issues, Brubaker says, as are women with irregular—or a lack of—menstrual cycles. (That indicates irregular hormone levels, which can also adversely affect bone health.)
Bottom line: Recreational riders and multi-sport athletes are most likely in the clear. But serious endurance cyclists should make sure they're doing weight-bearing exercises and make it out on the mountain bike. A 2002 study published in the journal Bone found that mountain biking provides more impacts to stimulate bone growth than road cycling.