Department of Biomedical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark.
Int J Obes (Lond). 2010 May;34(5):871-7. doi: 10.1038/ijo.2010.11. Epub 2010 Feb 16.
To elucidate if fat oxidation at rest predicts peak fat oxidation during exercise and/or metabolic phenotype in moderately overweight, sedentary men.
Cross-sectional study.
We measured respiratory exchange ratio (RER) at rest in 44 moderately overweight, normotensive and normoglycemic men and selected 8 subjects with a low RER (L-RER, body mass index (BMI): 27.9+/-0.9 kg m(-2), RER: 0.76+/-0.02) and 8 with a high RER (H-RER; BMI 28.1+/-1.1 kg m(-2), RER: 0.89+/-0.02). After an overnight fast, a venous blood sample was obtained and a graded exercise test was performed. Fat oxidation during exercise was quantified using indirect calorimetry.
Peak fat oxidation during exercise was higher in L-RER than in H-RER (0.333+/-0.096 vs 0.169+/-0.028 g min(-1); P<0.01) and occurred at a higher relative intensity (36.2+/-6.6 vs 28.2+/-3.1% VO(2max), P<0.05). Using the International Diabetes Federation criteria, we found that there was a lower accumulation of metabolic risk factors in L-RER than in H-RER (1.6 vs 3.5, P=0.028), and no subjects in L-RER and four of eight subjects in H-RER had the metabolic syndrome. Resting RER was positively correlated with plasma triglycerides (P<0.01) and negatively with plasma free fatty acids (P<0.05), and peak fat oxidation during exercise was positively correlated with plasma free fatty acid concentration at rest (P<0.05).
A low RER at rest predicts a high peak fat oxidation during exercise and a healthy metabolic phenotype in moderately overweight, sedentary men.
阐明静息时脂肪氧化是否能预测超重、久坐男性在运动时的脂肪氧化峰值和代谢表型。
横断面研究。
我们测量了 44 名超重、血压正常和血糖正常的男性在静息状态下的呼吸交换率（RER），并选择了 8 名低 RER（L-RER，体重指数（BMI）：27.9+/-0.9 kg m(-2)，RER：0.76+/-0.02）和 8 名高 RER（H-RER；BMI 28.1+/-1.1 kg m(-2)，RER：0.89+/-0.02）的受试者。禁食过夜后，抽取静脉血样并进行分级运动试验。使用间接测热法量化运动时的脂肪氧化量。
运动时脂肪氧化峰值在 L-RER 中高于 H-RER（0.333+/-0.096 对 0.169+/-0.028 g min(-1)；P<0.01），且发生在更高的相对强度（36.2+/-6.6 对 28.2+/-3.1% VO(2max)，P<0.05）。根据国际糖尿病联合会的标准，我们发现 L-RER 中代谢危险因素的积累低于 H-RER（1.6 对 3.5，P=0.028），且 L-RER 中没有受试者和 H-RER 中有四名受试者患有代谢综合征。静息 RER 与血浆甘油三酯呈正相关（P<0.01），与血浆游离脂肪酸呈负相关（P<0.05），运动时脂肪氧化峰值与静息时血浆游离脂肪酸浓度呈正相关（P<0.05）。
静息时低 RER 可预测超重、久坐男性在运动时的脂肪氧化峰值较高和代谢表型健康。
