Weight Loss: Cardio vs. Calorie Restriction

Ivanhoe Newswire
Thursday, November 23, 2006; 12:00 AM

By Lucy Williams, Ivanhoe Health Correspondent

ORLANDO, Fla. (Ivanhoe Newswire) -- Need to lose weight, but don't know the best way to start? If you're in your 50s, cardiovascular exercise may be your best option.

Diet and exercise are both effective ways to lose weight. But if you're over 50, you may want to hit the treadmill to help maintain muscle mass when you're dropping pounds. A new study reveals caloric restriction promotes weight loss, but it may result in loss of muscle and aerobic capacity.

"The systems responsible for moving the body, the musculature and the cardiovascular systems, are being used in exercise-induced weight loss, therefore the body preserves them," study author Edward Weiss, Ph.D., of Saint Louis University in St. Louis, told Ivanhoe. "In the case of caloric restriction or diet-induced weight loss, there are fewer demands put on these systems, so the body degrades the tissues responsible for delivering oxygen and producing muscular force."

Over 12 months, researchers studied healthy men and women between 50 years and 60 years who lost weight through either diet or exercise. Prior to weight loss, participants had body mass indexes between 23 and 30, so they were either overweight or on the heavy side of the healthy weight BMI range. Dieters reduced their caloric intake between 16 percent and 20 percent. Exercisers engaged in 60 minutes to 90 minutes of cardiovascular activity six times a week and aimed to burn 16 percent to 20 percent of consumed calories. Both groups achieved weight loss, but exercisers achieved greater overall health benefits.

Exercise challenges the muscles and prevents them from degrading. A person who loses weight without exercising places fewer challenges on the body. In addition, body mass challenges muscles during everyday routines like walking and climbing stairs. Loss of body mass means the body does not expend as much energy completing regular tasks.

Exercisers invested an hour to an hour-and-a-half nearly every day to lose weight and make physical gains. It may seem time-consuming, but time invested in exercise could help you live longer and have a better quality of life.