What other intervention can claim results like these?

Even studies of older, hospitalized patients show a beneficial effect from multidisciplinary interventions that include exercise. Those randomized to such interventions in the hospital were more likely to be discharged to go home, and to spend less time in the hospital over all — and at a lower cost.

Although we don’t think of it this way, you can make a pretty good argument that exercise is as good as drugs for many conditions. A 2013 meta-analysis of meta-analyses (that’s how much data we have) combined and analyzed the results from 16 reviews of randomized controlled trials of drug and exercise interventions in reducing mortality. Collectively, these included 305 trials with almost 340,000 participants.

Diuretic drugs (but not all drugs) were shown to be superior to exercise in preventing death from heart failure. But exercise was found to be equally good as drugs in preventing mortality from coronary heart disease. Exercise was better than drugs in preventing death among patients from strokes.

Many people will be surprised at how little you need to do to achieve these results. Years ago, in an effort to get in shape, I tried the P90X routine. It proved too hard for me. Later, when I tried the Insanity workout, it beat me so badly that people at work kept asking me if I was ill. Two years ago, I tried P90X3. It was a bit more manageable, but I still couldn’t keep it up.

I have not been alone in thinking that physical activity to improve health should be hard. When I hear friends talk about exercising, they discuss running marathons, participating in CrossFit classes or sacrificing themselves on the altar of SoulCycle. That misses the point, unfortunately. All of these are much more than you need to do to get the benefits I’ve described.

The recommendations for exercise are 150 minutes per week of moderate intensity physical activity for adults, or about 30 minutes each weekday.

Moderate intensity is probably much less than you think. Walking briskly, at 3 to 4 miles per hour or so, qualifies. So does bicycling slower than 10 miles an hour. Anything that gets your heart rate somewhere between 110 and 140 beats per minute is enough. Even vacuuming, mowing the lawn or walking your dog might qualify.