長期aerobic運動処方実践による糖・脂質代謝・肥満の改善と運動強度・頻度・期間との関係

Abstract

Effectfs of unsupervised long-term aerobic exercise on glucose, lipids metabolism and obesity were investigated. In 47 patients with glucose intorelance, impaired lipoprotein metabolism or obesity, maximum aerobic power (VO2max) was predicted from the results of treadmill test under Balke's protocol. Aerobic exercise program, devised by Cooper (1970, '72, '77) to quantify intensity, duration and frequency of exercise so that different activities and sports, such as walking, jogging, cycling, swimming etc., were exchangeable each other, was prescribed for each patients in accordance with the fitness classification. Each patient was instructed to perform unspervised exercise with the intensity kept within 40-70 % VO2max refering to own pulse rate. Meanwhile, OGTT, levels of serum lipids and body weight were examined. Criteria of improvement had been set up in advance. The results were analyzed with reference to exercise records including intensity of actually performed exercise, which was calculated by means of documents of self-measured pulse rate immediate after each exercise, or by means of heart rate during exercise determined from a heart rate recorder.Overall results showed improvement rates of 22.9% in 35 patients engaged in exercise with an exercise intensity of below 40 % VO2max (low intensity exercise, LIE), and 73.8% in 42 patients with an exercise intensity of 40-70% VO2max (moderate intensity exercise, MIE) . The proportion of patients belonging to MIE group was significantly (P<0.001) higher in the patient group obtained improvement in glucose, lipids metabolism or obesity, comparing to patients without improvement. No significant differences in improvement rates were seen between the patient groups whose exercise duration were below 1 year, 1-2 years and above 2 years, and, between the patient groups whose exercise frequencies were 3-4 times per week or above 5 times, when analysed within each of the LIE or MIE groups respectively. Improvement rates were significantly (P<0.05-0.001) higher in MIE group comparing to LIE group, when analysed within each of the patient groups whose exercise duration were below 1 year, 1-2 years and above 2 years, and, between the patient groups whose exercise frequencies were 3-4 times per week and above 5 times respectively. The results suggested that 1) exercise intensity rather than exercise frequency or duration was the more important factor, and 2) exercise with the intensity kept within 40-70% VO2max provided beneficial effects, in improving glucose, lipids metabolism or ohesity.