Exercise in the treatment of type 2 diabetes

ABSTRACT

Unlike the type 1, type 2 diabetes benefits from an improvement in glycaemic control, because of the effect of exercise on insulin sensitivity. The level of improvement is comparable to that achieved with pharmacological agents. This is significant where cost is a major consideration. These positive effects of exercise are maintained only if exercise is sustained. The effect of a single bout of exercise lasts from 12-48 hours, so exercise should be performed at least every other day or preferably every day. Improvement in glycaemic control with exercise is not related to level of fitness so everyone can benefit, as long as glycogen depletion is achieved, with results from moderately intense exercise for a reasonable duration of time. Even more important than glycaemic control is the benefit of reducing the risk of developing coronary events. Cardiovascular abnormalities are commonly seen in diabetes especially in those persons with type 2 and this is all related to the state of insulin resistance. Exercise also reduces the progression of metabolic abnormalities from mild to more severe forms of diabetes mellitus. The exercise prescription must consider socioeconomic and personal factors in addition to scientific criteria of exercise intensity. The current trend is to recommend a combination of modest, high-volume resistance training and aerobic training. Diabetes have a lower VO2max than normal individuals and so should not be placed on the same programmes. Flexibility is advised. For example, although the exercise period may be an hour long, little rest periods at intervals will not undo the metabolic benefits.(AU)