What Is Important About Exercise?

By editor | October 10, 2007

Exercise has great importance as part of the medical management of the person who has diabetes mellitus. The best exercise program is one in which aerobic activity is done for a period of 20 to 30 minutes on a daily or every-other-day basis.

Benefits Of Exercise

There are many benefits of exercise, and they far outweigh the risks. Some of these benefits are improved heart and breathing actions. A most common benefit recognized is the increase in muscular strength and endurance. There is a buildup of lean body mass and a decrease in body fat. The range of motion and the flexibility of the arms and legs are improved. Triglycerides and cholesterol are lowered. High-density lipoproteins (HDLsj the “good guys”) are increased, while low-density lipoproteins (LDLsj the “bad guys”) are decreased. Blood-pressure control is improved. Depression is decreased. The pain threshold is increased. Both self-image and self-esteem are improved, and, most important, a sense of well-being is achieved and enhanced.

There are benefits that are even more specific to diabetes management. Some of these are the increased sensitivity of the cell-receptor site to insulin. This sensitivity is noted as a decline in blood-glucose levels due to the improved use of insulin by the cells. The result is a reduction in the total insulin needed.

As exercise is maintained, there is a prolonged blood-glucose-lowering effect. Extensive short-term exercise may even result in lowered blood-glucose levels over a pehod of 24 to 36 hours. Some look at exercise as having a possible effect on the length of beta-cell function, especially for those with Type 2 diabetes and those with newly diagnosed Type 1 diabetes mellitus. All of these factors lead, directly and indirectly, to a decreased risk for atherosclerosis (one type of blood vessel/heart disease).

Aerobic exercise can be low, moderate, or severe in intensity.

It may be rhythmic, but it must be continuous that is, while walking at varying rates is fine, walking, then stopping, then walking is not aerobic. Exercise must be of a certain duration (a minimum of 30 minutes, three times a week, or 20 minutes, five to six times a week).

The major fuels used for aerobic exercise are glucose and free fatty acids. Good aerobic exercises are swimming, walking, rowing, cycling, and dancing . Cross-country (Nordic) skiing is the most effective of all aerobic exercises. Notice that jogging and other high-impact or “severe” aerobics have not been placed on this list. There have been too many risks found with such exercise; for the diabetic in particular, the risks outweigh the benefits. Therefore, walking or other low-impact aerobic exercise is recommended.

For an exercise to be aerobic, the heart rate must be at least 50 percent above the resting heart rate. The ceiling level is 75 to 80 percent. The ideal range is between 50 and 75 percent. The common target range recommended is from 60 to 80 percent.)

To determine your target zone or ideal range, first subtract your age from 220. Then multiply this number by 60 percent (or another number, depending on a recommendation by your physician) to obtain your threshold level (the lower number of the range of beats per minute that you aim for during your exercise period). Multiplying the same number by 75 percent will give you your ceiling level. You should aim to maintain a heart rate in this “ideal” range for 20 to 30 minutes. (To feel your heartbeat, place your second and third fingers on the inner side of your wrist or on your neck about three inches below the end of your ear.)

Since you are unable to determine your heart rate every minute unless you have a monitor in place, you can gain a rough estimate of how hard you are exercising by using the “Borg Scale of Perceived Exertion.” The scale goes from six to twenty. Less than six would mean sleep or a resting state, while twenty would mean activity to the point of fatigue. Seven would be very, very light activity; nine would be light, and eleven somewhat light. Nineteen is very, very hard; seventeen is very hard; fifteen is hard; and thirteen is somewhat hard. You would try to exercise in the range of twelve to sixteen, or the aerobic intensity level.

Activities such as weight lifting, gymnastics, and some sports related activities (e.g., wrestling) are isokinetic exercises. This type of exercise uses glycogen or stored glucose as the major source of fuel. These activities are intermittent, of short duration, and usually quite intense. They are called anaerobic (the person doesn’t increase oxygen intake much over usual levels, unlike in aerobic exercise). Anaerobic activities do not offer as much benefit to the person who has diabetes, and in fact they may raise the blood pressure to the point of putting the body at risk.


Tagged under:

Share This

Topics: Diabetes Care |

Comments

You must be logged in to post a comment.