Every afternoon, Georgetown Medical Center professor Dr. Harry Preuss walks for an hour, going outside if it is sunny or trotting up and down the halls if it is cloudy. He wears a pedometer to count his steps, aiming for 15,000 steps by the end of the day, or about 7.5 miles, according to his estimates.
The professor of physiology, medicine and pathology has been exercising for the past 10 years, going for daily walks and lifting weights two to three times a week in his home gym for the past four to five years.
"It's not only for young males who want to look like Adonis, but it's for older men and women," says Dr. Preuss, co-author of "The Natural Fat-Loss Pharmacy, Drug-Free Remedies to Help You Safely Lose Weight, Shed Fat, Firm Up, and Feel Great."
"If you can keep your muscles up and not develop sarcopenia, or lack of muscle, you can remain independent and live mobile a lot longer," he says.
Regular aerobic exercise and resistance training, along with a calorie-restricted diet, are keys to building muscle and losing fat, according to metro-area physicians, nutritionists and dietitians.
"You need to focus on burning calories, not fat," says Shelley Goldberg, a registered dietitian and certified personal trainer. She is director of nutrition communication for the International Food Information Council, a provider of science-based information on food safety and nutrition based in Northwest.
A pound of fat is made up of 3,500 calories of stored energy, Ms. Goldberg says. Cutting back by 500 calories a day, or increasing exercise to burn 250 calories and reducing caloric intake by 250 calories can eliminate 1 pound of fat over the course of a week, she says. Losing 1 to 2 pounds a week is the maximum weight loss that can be sustained, she says.
"I wouldn't recommend more than that. A lot of people tend to gain it back," she says.
Performing 30 minutes of low-intensity aerobic exercise burns about 200 calories, with 120 calories, or 60 percent, coming from stored fat, Ms. Goldberg says, citing the American Council on Exercise, based in San Diego. With high-intensity exercise, 400 calories are burned in 30 minutes with 140 calories, or 35 percent, coming from fat, she says.
"While it is true that a higher proportion of calories burned during low-intensity exercise come from fat, high-intensity exercise still burns more calories from fat in the final analysis," she says.







