Even Low-Intensity and Low-Volume Exercise Training May Improve Insulin Resistance in the Elderly

Abstract

Moderate to high intensity exercise training is known to ameliorate the coronary risk factors in relation to an improvement in body composition. However, the benefit of low-intensity and low-volume training for these risk factors remains unclear in elderly people. Therefore, we investigated the effects of low-intensity and low-volume exercise training on blood lipid values and insulin resistance in the elderly. A total of 56 healthy elderly individuals (42 females and 14 males) aged 64+/-6 years participated in a 12-week exercise program, comprising aerobic training and resistance training. After the program, there were no significant changes in high-density lipoprotein cholesterol, triglyceride serum levels, or in peak oxygen uptake on average. However, the homeostasis of minimal assessment of insulin resistance (HOMA-IR) value was significantly reduced by 21%. The participants were categorized into tertiles based on initial Body Mass Index (BMI). The Middle-BMI group (non-obese subjects) showed reduced HOMA-IR (2.0-->1.3, P<0.01), but this reduction was not associated with the reduction in BMI (r=0.08, P=0.74), whereas the two reductions were significantly associated in the High-BMI group (r=0.61, P=0.01). Even low-intensity and low-volume exercise training, which would ordinarily be insufficient for improving mean lipid values or aerobic fitness, was found to be effective in improving insulin resistance in the elderly. The improvement in insulin resistance was independent of the improvement in obesity.