Are You Bone-Building?
High-impact exercise has a (very important) place in your regimen.
Your body can—and should—take a pounding.
Hear us out: High-impact exercise gets a pretty bad rap by those who believe burpees destroy your knees and that distance runners are destined to hobble. However, research suggests weight-bearing exercises are actually better for long-term bone health than non weight-bearing activities.
Think of bone-building like muscle-building. When you lift weights, you stress your muscles, causing micro-trauma. With rest and recovery, they grow stronger. “To build bone, you need to put stress on the bone, and that stress has to be significant enough to cause a disruption,” says Wayne L. Westcott, Ph.D., a professor of exercise science at Quincy College in Massachusetts. “Then the bone rebuilds and becomes stronger.”
Alas, the reason high-impact, pavement-pounding exercise took flight: It’s the secret to strong bones, powerful muscles, and even—if you’re careful—injury prevention.
But of course there are necessary limitations. Too much of any kind of exercise can introduce the risk of overuse injury. Below, experts reveal how to reap the benefits of high-impact the smart way.
1. Think hard and fast: Running involves both concentric (shortening) and eccentric (lengthening) muscle contractions, explains Westcott. The eccentric helps build bone density: Upon landing, your muscles absorb your body weight, he says. Cycling and swimming don't have eccentric contractions. There’s no stretching the muscles under force, he explains.
Intensity matters, though: “Bones respond to loads that are high magnitude (i.e. heavy) or high rate (i.e. fast). Impact is high rate, so it’s very good for bones,” says Steven Hawkins, Ph.D., a professor of exercise science at California Lutheran University. “Movement that is low magnitude or low rate provides little stimulus to bones.” High-impact exercise will likely develop strength and power characteristics of muscle, he adds.
2. Don’t fear the downhill: “In muscle building, we always get better results with eccentric movements,” says Westcott. It’s counterintuitive because you think gravity is doing the work when you walk downhill or lower a barbell, but as he says: “You have the control.” On a downhill as well as on the lowering portion of a lift, your muscles are attenuating the force of gravity, being stretched and stressed, which causes a little more micro-trauma, Westcott explains. “The bone responds the same way.”
3. Jump to it: Plyometric moves like box jumps are a win-win: They build bone and muscle, says Westcott, largely because they emphasize that eccentric muscle action. Some evidence suggests this could help you keep you on the road. One small study in The Journal of Athletic Training found that jumping movements stabilized athletes’ adductor and abductor muscles, upping their joint stability, potentially slashing injury risk. Skip the weighted vests, though—your bodyweight is usually enough, notes Westcott.
4. Variety is everything: As with most aspects of movement, bones will respond to any activity that is new, says Hawkins. So if you’re already a runner, take up basketball, volleyball, or gymnastics. Or consider incorporating more plyometrics into your routine.