
                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: TUESDAY, February 5, 1991                   TAG: 9102050082
SECTION: EXTRA                    PAGE: E6   EDITION: STATE 
SOURCE: DONNA RASKIN THE NEW YORK TIMES
DATELINE:                                 LENGTH: Medium

HOW MUCH TO EXERCISE? HERE ARE NEW GUIDELINES

Regular exercisers, from tennis players to aerobic dancers, typically spend an hour huffing and puffing through their allotted fitness routine. Many people think that anything less just isn't a workout and anything more cuts into the rest of their lives.

But how many hours a week provides the optimum workout and what kind of exercise will benefit our overall level of fitness?

In 1990, the American College of Sports Medicine revised its 1978 position paper detailing physical fitness recommendations for adults.

The group is the nation's leading sports and exercise research organization, gathering statistics and data to set guidelines for the public, as well as professional and amateur athletes regarding healthy and effective ways to stay in shape.

The 1990 guidelines are:

Train three to five days a week.

Exercise at an intensity level of 60 to 90 percent of maximum heart rate, or 50 to 80 percent of maximum oxygen uptake or maximum heart-rate reserve.

Exercise at your maximum heart-rate level for at least 20 to 60 minutes each session. It is also recommended that non-athletes exercise at lower intensities for longer periods to guard against injury.

Exercise should be rhythmical and aerobic using large muscle groups. Examples: walking, jogging, bicycling, rowing and stair-climbing.

Resistance training, done with or without weights at moderate intensity to maintain fat-free weight, should not be considered an aerobic exercise. One set of eight to 12 repetitions of eight to 10 exercises that condition the major muscle groups should be performed at least two days a week.

The important addition of resistance training, that is, the use of free weights, weight machines or calisthenics to increase or maintain muscular strength and endurance, is perhaps the most significant finding in the 12 years between the publication of the position papers.

"We followed runners for 10 years and found they were wasting away on top," said Dr. Michael Pollock, Ph.D., director of the Center for Exercise Science at the University of Florida and chairman of the subcommittee reviewing the position paper.

"We cite studies in which runners who didn't practice upper-body training were found to have an overall loss of muscle mass. People require strength training in order to maintain an active life style."

While the above guidelines refer to being able to do medium-to-difficult physical tasks without becoming too fatigued, and maintaining that ability throughout life, it is also noted that adults can still positively affect their general health with less exercise.

A less-strenuous program of exercise, however, may not significantly improve cardiovascular abilities or help to maintain a proper body-mass index.

Body-mass index refers to the ratio of fat to muscle in a person's weight and is a more reliable indicator of true health than simply knowing your weight in pounds.

Although the exercise-frequency levels remained the same - three to five times a week - duration and intensity levels were updated. The new recommendations, training at 60 to 90 percent of maximum heart-rate reserve for 20 to 60 minutes, was increased from a minimum of 15 minutes, and intensity levels were also raised 15 to 30 percent.

by CNB