Principles of Exercise

A basic principle of exercise for individuals over forty years of age, according to Glenn Swengros, an American authority on physical fitness who has served as Director of Program Development for the President's Council on Physical Fitness, is to avoid incurring a large oxygen debt. An oxygen debt is brought on during the performance of anaerobic (without oxygen) exercise.

In this type of work, the exercise is so intense that the body is just not able to supply itself with sufficient oxygen. The oxygen must be repaid quickly, and to do that, the activity must stop or slow down considerably until the debt is repaid.

Anaerobic exercises are necessary for athletic training, but are of lesser value in a personal physical fitness program. In fact, if you have been sedentary or if the heart is damaged, this type of exercise could be harmful.

Most experts would suggest that you should concentrate on aerobic exercise (activities that do not develop an oxygen debt) to improve cardio-respiratory fitness, the most important type of fitness for adults.

The same principle applies to warm-ups. Perform a warm-up of 5-10 minutes before engaging in an all-out muscular activity, especially if your workout takes place first thing in the morning.

ISOMETRICS - USE CAUTION. If you have a heart condition, check with your physician. Then run and walk--but don't use isometric exercises.

According to researchers at the University of Texas Medical School, isometric exercises--the ones that pit muscles against other muscles or an immovable object--can cause blood pressure to rise.

Jogging, on the other hand, increases the oxygen uptake while maintaining a much lower blood pressure.