van Baak M A
NUTRIM, Department of Human Biology, Maastricht University, The Netherlands.
Int J Obes Relat Metab Disord. 1999 Apr;23 Suppl 3:S11-7. doi: 10.1038/sj.ijo.0800879.
Together with diet and behavioural modification, regular exercise is one of the key components of programs for the treatment of obesity. It appears to be one of the major factors determining the long-term success of weight loss programs. One of the mechanisms that may underlie this and other beneficial effects of regular exercise is the effect of exercise training on substrate utilisation. Exercise training increases fat oxidation in lean subjects. The capacity to mobilise and oxidise fat has been shown to be impaired in obese and post-obese subjects. Thus, an increase in the capacity for fat oxidation may help to maintain fat and energy balance at a lower fat mass in individuals with a predisposition for obesity. However, in view of the impaired fat oxidation in obese and post-obese individuals the question arises whether exercise training also increases fat oxidation in the obese. Few studies have addressed this question and have investigated the effect of exercise training on substrate utilisation in obesity. Addition of an exercise training program has been shown to prevent the reduction of basal fat oxidation that is associated with diet-induced weight loss in two studies. No effect of additional exercise training on substrate oxidation during exercise was found. In post-obese subjects exercise training caused no change in 24 h substrate oxidation in one study and increased carbohydrate, rather than fat oxidation in another. In obese subjects neither low (40% maximal aerobic fitness (VO2max)) nor high (70% VO2max) intensity training was found to affect resting substrate oxidation. During exercise fractional fat oxidation was increased after low, but not after high intensity training. The question, whether exercise training increases fat oxidation in obese and post-obese as in lean subjects therefore cannot be answered conclusively at this point in time and requires further study. The role of exercise intensity and type of exercise needs to be studied as well.
与饮食和行为改变一起，规律运动是肥胖治疗方案的关键组成部分之一。它似乎是决定减肥计划长期成功的主要因素之一。规律运动的这一以及其他有益效果可能的潜在机制之一是运动训练对底物利用的影响。运动训练可增加瘦人脂肪氧化。已证明肥胖者和肥胖后人群动员和氧化脂肪的能力受损。因此，增加脂肪氧化能力可能有助于易肥胖个体以较低脂肪量维持脂肪和能量平衡。然而，鉴于肥胖者和肥胖后个体脂肪氧化受损，运动训练是否也能增加肥胖者的脂肪氧化就成了问题。很少有研究探讨这个问题，也很少研究运动训练对肥胖者底物利用的影响。两项研究表明，增加运动训练计划可防止与饮食诱导的体重减轻相关的基础脂肪氧化减少。未发现额外运动训练对运动期间底物氧化有影响。在一项研究中，运动训练对肥胖后人群的24小时底物氧化没有影响，而在另一项研究中，运动训练增加了碳水化合物而非脂肪的氧化。在肥胖者中，低强度（最大有氧适能的40%（VO2max））和高强度（VO2max的70%）训练均未发现影响静息底物氧化。在运动期间，低强度训练后脂肪氧化分数增加，而高强度训练后则没有增加。因此，运动训练是否像在瘦人身上那样增加肥胖者和肥胖后人群的脂肪氧化，目前还无法得出确切答案，需要进一步研究。运动强度和运动类型的作用也需要研究。
