Regular weight-bearing exercise, including running and walking, is important too.

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Because you can get the exercise you need from walking your dog vigorously, running with your dog, doing some push-ups at home, or just playing.

WHITEHOUSE: President's Council on Fitness, Sports & Nutrition

The 2008 Physical Activity Guidelines for Americans released by the Department of Health and Human Services recommends that adults age 18 to 64 engage in at least 2.5 hours of moderate-intensity aerobic exercise (brisk walking, biking) or an hour and 15 minutes of vigorous activity (like running) each week.

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