Exercise as medicine

It’s long been known that working out is good for the brain, but, until recently, scientists didn’t know why. It turns out that when we work out our muscles produce a protein called cathepsin B, which promotes the production of new brain cells. In the studies that resulted in this finding, the people (and mice) were running on treadmills. I don’t know if a less rigorous workout would lead to this brain-enhancing effect. I hope so.

But there are plenty of health benefits that don’t require running. I recently came across an analysis of 305 randomized controlled trials (340,000 participants) showing how exercise can be almost a “miracle cure.” Here is a sampling of the conclusions:

• Osteoarthritis of the knee: improves both pain and function.
• Rheumatoid arthritis: increases aerobic capacity and muscle strength.
• Heart attacks: reduces all-cause mortality by 27 percent and cardiac mortality by 31 percent.
• Heart disease: as good as drugs in preventing mortality.
• Diabetes: helps control blood sugar.
• Depression: improves symptoms.

You can reap these benefits by exercising (moderate intensity) 30 minutes five times a week. Walking or bicycling can do the trick; even vacuuming and lawn mowing. The idea is to get your heart rate between 110 and 140 beats per minute. I have an Apple watch with a heart rate counter (which I generally ignore). But today at Jazzercise I paid attention, and found that I got a high reading of 129, though more often it was around 108.

Commenting on the “meta analysis” of the benefits of exercise, editors at the British Medical Journal noted that, while exercise isn’t really a miracle cure, it is nevertheless “the best buy for public health.” I wish that lying on the couch and reading (a favorite pastime) had similar health benefits.

For an introduction to this blog, see I Just Say No; for a list of blog topics, click the Topics tab.