Carter Rebecca A, McCutcheon L Jill, Valle Emanuela, Meilahn Elaine N, Geor Raymond J
Department of Animal and Poultry Sciences, College of Agricultural and Life Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech and University of Maryland, Blacksburg, VA 24061, USA.
Am J Vet Res. 2010 Mar;71(3):314-21. doi: 10.2460/ajvr.71.3.314.
To determine effects of exercise training without dietary restriction on adiposity, basal hormone and lipid concentrations and glucose and insulin dynamics in overweight or obese, insulin-resistant horses.
12 overweight or obese (body condition score > or = 7), insulin-resistant (insulin sensitivity < or = 1.2 x 10(-4) L/min/mU) geldings.
4 horses remained sedentary, and 8 horses were exercised for 4 weeks at low intensity and 4 weeks at higher intensity, followed by 2 weeks of detraining. Prior to and after each training period, frequently sampled IV glucose tolerance tests with minimal model analysis were performed and baseline plasma insulin, glucose, triglycerides, non-esterified fatty acids, and leptin concentrations were analyzed. Adiposity was assessed by use of morphometrics, ultrasonic subcutaneous fat thickness, and estimation of fat mass from total body water (deuterium dilution method).
Body weight and fat mass decreased by 4% (mean +/- SD, 20 +/- 8 kg) and 34% (32 +/- 9 kg), respectively, compared with pre-exercise values, with similar losses during low- and higher-intensity training. There was no effect of exercise training on subcutaneous fat thickness, plasma hormone and lipid concentrations, or minimal model parameters of glucose and insulin dynamics.
Results suggested that moderate exercise training without concurrent dietary restriction does not mitigate insulin resistance in overweight or obese horses. A more pronounced reduction in adiposity or higher volume or intensity of exercise may be necessary for improvement in insulin sensitivity in such horses.
确定在不限制饮食的情况下进行运动训练对超重或肥胖、胰岛素抵抗马匹的肥胖程度、基础激素和脂质浓度以及葡萄糖和胰岛素动态变化的影响。
12匹超重或肥胖（身体状况评分≥7）、胰岛素抵抗（胰岛素敏感性≤1.2×10⁻⁴L/分钟/毫单位）的去势雄马。
4匹马保持 sedentary，8匹马先进行4周低强度运动训练，再进行4周高强度运动训练，随后进行2周的停训。在每个训练期之前和之后，进行频繁采样的静脉葡萄糖耐量试验并采用最小模型分析，同时分析基线血浆胰岛素、葡萄糖、甘油三酯、非酯化脂肪酸和瘦素浓度。通过形态测量学、超声皮下脂肪厚度以及根据总体水（氘稀释法）估算脂肪量来评估肥胖程度。
与运动前相比，体重和脂肪量分别下降了4%（平均±标准差，20±8千克）和34%（32±9千克），在低强度和高强度训练期间的下降幅度相似。运动训练对皮下脂肪厚度、血浆激素和脂质浓度或葡萄糖和胰岛素动态变化的最小模型参数没有影响。
结果表明，在不限制饮食的情况下进行适度运动训练并不能减轻超重或肥胖马匹的胰岛素抵抗。对于改善此类马匹的胰岛素敏感性，可能需要更显著地降低肥胖程度或增加运动的量或强度。
