Because physical effort can lead to fatigue, a special holiday was developed to honor those who labor with a day designated for rest and relaxation. Labor Day came after the harvest, and was perfectly designed for an agrarian society. It was particularly appreciated by those who needed a day off for rest, recovery and recuperation. Indeed, if physical activity is the norm, than rest is essential.

Unfortunately, at least in many ways, such is not the case for most Americans in 1998. We tend to do very little physical activity, either in our occupational responsibilities or in the way of regular exercise. In fact, the surgeon general's report indicates that from a movement perspective, about three-quarters of the population could be reclassified as statues because we are so sedentary.

What does this imply with respect to Labor Day. Basically, because most laborers are not doing much physical activity, a rest day is not an appropriate change of pace from their normal routine. Please don't misunderstand. I am not implying that desk workers are lazy. Jobs demanding much mental effort may be more stressful in many ways than jobs requiring lots of muscular exertion. In fact, office employees typically have more difficulty sleeping than those who do manual labor. The process goes something like this, and it may be all too familiar to many of you.

You wake up feeling semi-rested and sluggish, and you can't really get your metabolism in gear until you've had a couple cups of coffee. You understand the value of a substantial breakfast, but you're already overweight, you're not really very hungry, and you're a little too late for work. Throughout the day you experience relative highs and lows energy-wise, as different situations and circumstances gain and lose your attention. After a quick lunch you feel a little drowsy during the mid-afternoon hours, but rally to finish most of your work in time for the evening commute home. You're happy to be back in your own house and enjoy a good dinner in a less stressful atmosphere. You would really like to do some exercise, but you're just too worn out from the day's demands, and you choose to relax in front of the television instead. You feel tired but you have difficulty falling asleep, and awake the next morning less rested than you had hoped. The cycle continues and, in a sense, your days and nights seem somewhat similar. You're never fully awake and you're never soundly asleep. Your mind never rests and your body never works like it should-or at least never works out like it should. Even worse, you're gaining weight in spite of eating the same amount of food. Eventually, you become discouraged, but you don't know how to break the cycle of mental stress and physical inactivity.

I suggest that you take a different approach to Labor Day this year. Instead of a big picnic or resting at the beach, do something that should be a welcome change of pace for your body. Look at it this way. If you are physically active, an appropriate change of pace is a day of rest. However, if your lifestyle is sedentary, then a desirable change of pace is a day of moderate activity. Determine to exercise your muscles sensibly by: (1) renting a canoe and gently paddling around a lake or down a river; (2) driving to a nearby park or mountain and carefully walking/hiking an hour or so to a scenic picnic location; (3) pumping up the tires on your bicycle and respectfully riding the back roads or bike trails; (4) any other relatively mild physical activity that you enjoy.

You should find that your body responds positively to appropriate exercise, that you make more nutritious food selections, that you sleep better at night, and that you feel more energetic throughout the day. Of course, one day a year of physical activity is not nearly sufficient. So how do you incorporate a sensible exercise plan into your daily lifestyle?

This is potentially more difficult until you attain a level of fitness that reinforces your exercise efforts. Our research indicates that this typically requires about 8-10 weeks of regular and progressive exercise, with gradual and systematic increases in the training intensity. Generally speaking, 20 minutes of strength training, 20 minutes of endurance exercise, or better yet a combination of both, done two or three days a week, is ideal for achieving excellent improvements in physical fitness and body composition.

I will address this issue through an informative slide presentation at the South Shore YMCA on Thursday, September 10th at 6:00 p.m. The focus will be on the benefits and guidelines for sensible muscular exercise that can be performed safely, effectively, and efficiently at home or a fitness facility. Sedentary adults, seniors, and golfers will find the presentation most relevant, although everyone is invited to participate. Articles on training principles and procedures will be distributed, and questions on exercise will be answered. There is no charge for the presentation, but please call Susan Ramsden at (617) 479-8500, x132 if you plan to attend for seating purposes.

Wayne L. Westcott, Ph.D., is fitness research director at the South Shore YMCA in Quincy, MA., and author of several fitness books including the new releases, Building Strength and Stamina and Strength Training Past 50.