Cycling has long been considered one of the easiest and safest ways to get exercise — it’s a great aerobic workout, it’s gentle on the joints, and pretty much everyone knows how to ride a bike.
But recent research suggests that cyclists may need to worry about more than just avoiding cars on the roads. People who devote too much time to cycling and don’t get enough other forms of exercise may have a higher risk of developing osteoporosis because their bones don’t get enough daily pounding.
It’s not something most recreational bikers need to worry about. But professional bikers probably need to consider their risk, sports doctors say.
Impact is important
“We’ve had 65-year-old men whose bones look like 65-year-old women. They’ve suffered fragility fractures,” said Dr Srinivas Ganesh — a sports medicine specialist with Kaiser Permanente in Redwood City — who is a cyclist himself.
“We tell them it’s great what they’re doing, but you need to realise that the bones underneath those muscles are not as strong as they could be,” he said. “I tell my cyclists that they’ve got to get out there and do something else too.”
Several recent studies have found that professional cyclists have lower bone mineral density — a measure of the risk of developing osteoporosis — than people of the same age who are moderately active but don’t bike.
Bones are designed to get regular impact, even if it’s just from walking around, and without that impact, the bones lose strength and density.
Cycling is often considered a healthy exercise because it’s no-impact — people don’t pound their joints the way they might with running or jumping. Biking is not as efficient as running if you want to lose weight. The average person will burn more calories in 30 minutes of running than an hour of cycling — but it’s not as hard on the body.
Don’t dismiss weight training
In fact, cycling can actually be part of rehabilitation for people with injuries. Easy pedalling on a stationary bike can get blood moving into an injured knee, for example.
But serious cyclists may spend so much time on their bikes that they end up with almost no weight-bearing activity. Cyclists would probably benefit from regular walks and hikes — or even better, a short, intense run a couple of times a week, said Dr Thor Besier, director of research at Stanford University’s Human Performance Lab.
“Bones and cartilage are designed to withstand pretty large impact loads, and they like that kind of loading,” Besier said. “Walking would provide much more stimulus for bone and cartilage health.”
Still, cyclists are often a stubborn bunch when it comes to getting off their bike. Elizabeth Hernandez-Jones, 41, picked up cycling four years ago as a hobby. She started by doing short rides around her neighbourhood. Today she’s done several 100-mile rides and is a recreational bike racer. And she’s lost 25 pounds, too.
“I know there are lots of women like me, who really want to do some form of exercise,” Hernandez-Jones said. “It doesn’t matter what your size or shape is, as long as you have some sort of pedal power.”