Miriam Nelson, one of the leading U.S. exercise researchers, walks along the Charles River Esplanade in Boston. She has written a new book T he Strong Women's Guide to Total Health .

WHY EXERCISE? WHY EXERCISE? • Even a little physical activity is better than none at all. • More physical activity equals greater health benefits. • Physical activity improves health regardless of body weight. • Both aerobic exercise and strength training improve health. • Almost everyone benefits from physical activity, from children to older adults, pregnant and post-partum women, people with disabilities and members of every racial and ethnic group. Source: The Strong Women's Guide to Total Health by Miriam Nelson and Jennifer Ackerman COUNT YOUR STEPS COUNT YOUR STEPS To increase your steps: Take 100 steps around your office or home about every hour. Program your computer to remind you when it's time to take a break. At the office, don't e-mail or call anyone within 400 feet of you. Instead, walk to that person and give him or her the message. Take the long way to the restroom. Take a couple of quick laps around the mall before you start shopping. Walk one city block, about 200 steps. Take a brisk walk during your lunch break for about 20 minutes or so, about 2,000 steps. Walk four laps around the track at a high school, 2,000 steps. Play basketball game for 30 minutes, more than 4,300 steps. Low-impact aerobic dancing for 20 minutes, more than 2,500 steps.



Play soccer for 1 hour, 8,000 to 10,000 steps. Benefits of a pedometer Just because you're busy doesn't mean you're active. For the real test of your physical activity, get a pedometer. Clip it to your waistband and wear it from the time you get out of bed until you go to sleep at night. Keep track for two or three days, then use these "steps per day" numbers to figure out where you are: Fewer than 4,500: You're very sedentary

4,500-5,500: You're sedentary

5,500 to 7,500: You're headed in the right direction but need to step it up

8,500 and up: You're active, stick with it A recent study found that people who wear a pedometer walk about 2,000 more steps a day or about another mile than those who don't. That burns about 100 extra calories a day. If your goal is to lose weight, you probably need to work up to 12,000 or more steps a day. Source: USA TODAY research Ladies, go take a hike. Or at least a brisk walk. Seriously. It may lower your risk of stroke and prevent the dreaded middle-age weight gain, new research shows. These findings join a long list of reasons why you should remain physically active. TO IMPROVE HEALTH: How much activity is needed? WALKING: An hour a day keeps the weight away CUSTOMIZE A PLAN: Quiz yourself to find the right walking routine And almost no one knows those reasons better than Miriam Nelson, 49, director of the John Hancock Research Center on Physical Activity, Nutrition and Obesity Prevention at Tufts University in Boston and co-author of a new book, The Strong Women's Guide to Total Health, with Jennifer Ackerman. Nelson is one of the country's leading researchers on exercise for women, and she co-chaired the committee that created the government's 2008 Physical Activity Guidelines for Americans. Many women complain about gaining weight during and after menopause, but a recent study found that some normal-weight women were able to prevent weight gain by doing an hour a day of moderate-intensity physical activity such as brisk walking. Say what? An hour a day? That amount is doable for most women, Nelson says, but it takes effort to do more activity all day long, including while traveling to and from work, socializing and playing with your kids or grandkids. Almost nothing is easier and cheaper than walking, but that means you need to get the lead out and put some spring into your step. It's not window shopping or taking a stroll in the park. "Brisk means that you get warm while walking and that, while you can carry on a conversation, you can't just gab forever — you need to speak in shorter sentences," she says. "You should feel that your heart rate is elevated. But it is not so intense that you are sweating a lot, unless, of course, it is hot outside. And remember that exercise intensity is relative. A brisk walk for one lady may be a stroll for another." Many women do less exercise as they age when they need to be doing as much or more, Nelson says. "It may be that we are exercising the same number of times a week, but the actual energy used during that time may be less because we aren't working out at the same intensity or speed. Also, we may be doing slightly less activity around the house with chores and gardening." Plus, many women don't strength-train, which means they are losing muscle mass, says Nelson, who has done numerous studies and books on the benefits. Lean tissue is what is metabolically active, she says. Loss of this tissue contributes to slowing metabolism. Weight training benefits the body in numerous ways, including improving bone, joint and muscle health; boosting the immune system; reducing depressive symptoms; and improving sleep. You can do as little as two sessions a week at a local fitness center or lift weights at home, she says, but make sure you're challenging yourself and lifting enough weight. Another great option: sit-ups, lunges, squats, push-ups and pull-ups, she says. You can do them on your living room floor while watching the news or playing with the kids. And now is certainly not the time to ignore your diet. One of the major keys to avoiding middle-age spread: closely monitoring your caloric intake, Nelson says. By far the biggest culprit of weight gain as people age is eating too much, she says, especially foods high in sugar and added fat. OK, counting calories doesn't take much time, but all that physical activity may sound like a lot to some women. Yet Nelson, a busy working mom, practices what she preaches. Most days she commutes by train to work and walks from the station to her office, which is about 25 minutes each way. She runs for an hour every Wednesday, Saturday and Sunday and rock-climbs once or twice a week, either at the gym or outside depending on the time of year. When the weather is nice, she swims and bikes once a week. And she squeezes in a five-minute routine every other day that includes sit-ups, push-ups and pull-ups. "I usually do these while I am watching the Red Sox play." Exercise is fun for her, she says. "I am lucky ... in that I love to be active. I find that because I sit most of the day, I really need to find the time to be active before and after work and on the weekends." Guidelines: You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. Read more