This is Bill White with the VOA Special English Science Report.
The American Heart Association is advising people to exercise by lifting weights. One of the writers of that advisory is Barry Franklin of William Beaumont Hospital in Royal Oak, Michigan. Mr. Franklin directs the exercise and education program for people with heart disease.
Mr. Franklin says doctors have increasing evidence that exercising with weights can reduce several risks for heart disease. For example, weight training improves the operation of the heart and blood vessels. It also increases the amount of muscle in the body. He says there is less demand placed on the heart when the muscles are stronger. He believes weight training will help a person's heart work better when the person has to lift or carry objects.
Weight training also improves the way the body burns sugar. Mr. Franklin says this kind of exercise helps people reduce body fat. He says a body with more muscle is able to burn more calories in food.
The American Heart Association advisory calls for people to lift weights at least two times a week. The advisory says training periods should include eight to ten different exercises. However, Mr. Franklin says weight training is not for everyone. He says it appears safe and helpful for healthy people and those at low risk for heart failure. But, he says more study is needed before it can be advised for patients with medium to high risk of heart disease.
The American Heart Association also recently published a study of the effects of weight training. That study shows that such training can lower blood pressure.
Researchers at Northern Illinois University examined eleven studies carried out during the past thirty years. More than three-hundred people took part in the studies. All of them exercised between two and five times a week for as long as one hour each time. However, only one-hundred-eighty of them trained with weights.
Researchers found that the people who used weights had lower blood pressure than the other people. The difference was even more apparent when blood pressure was taken while the heart was at rest. At those times the weight trainers' blood pressure was about four percent lower.
The Heart Association says weight training should be part of program that includes walking, stretching and eating a healthy diet.
This VOA Special English Science Report was written by Caty Weaver. This is Bill White.