How short? Twenty minutes, three times a week. But even less at first.
Federal guidelines advise Americans age 18 to 64 to get 21/2 hours a week of moderate-intensity or 75 minutes a week of vigorous-intensity aerobic physical activity.
Frank Comstock, Tucson, Ariz., doctor and author of the book "Antiaging 101," specializes in wellness and anti-aging. He insists that all it takes to truly be fit is an hour a week. So why not start there? Anything is better than nothing!
You'll also be happy to hear Comstock say, "If I'm out of shape, the last place I would go is a gym. You see all these machines, and you see these guys walking around. You don't know what you're doing. The key is to find something you like."
So, how does this 20-minute workout do the job? It's all about "interval training," he says, which means short bursts of higher intensity aerobics, then returning to shorter periods of lower intensity. For instance, walk at a normal pace for two minutes than as fast as you can for 20 or 30 seconds. Then repeat. Gradually increase the fast bursts and decrease the slow ones.
Find the exercise that is least objectionable, like walking, swimming, jump rope, jumping jacks, doing squats.
If you're just beginning, pick a shorter time — even 5 minutes twice a week — then build up slowly.
Don't give up. If you're at the 20 minute/three times a week level and just don't feel like exercising, employ the 10-minute rule. "Start your exercise session and plan on working out for only 10 minutes" that day, he recommends.
If that doesn't work, "look in the mirror." Sometimes, says Comstock. That'll probably be enough to get you back off the couch and into your interval zone again.
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