Gaine Patricia C, Viesselman Christian T, Pikosky Matthew A, Martin William F, Armstrong Lawrence E, Pescatello Linda S, Rodriguez Nancy R
Department of Nutritional Sciences, University of Connecticut, Storrs 06269, USA.
J Nutr. 2005 May;135(5):1088-92. doi: 10.1093/jn/135.5.1088.
Both exercise and dietary protein intake affect whole-body protein turnover (WBPTO). Few studies have investigated the effect of aerobic exercise training on WBPTO [leucine rate of appearance (Ra), oxidation (Ox), and nonoxidative leucine disposal (NOLD)] in untrained individuals consuming a specified level of protein. This study examined the effect of aerobic exercise training on WBPTO in untrained men and women during a controlled diet intervention providing 0.88 g protein/(kg . d). After a 2-wk adaptation to the study diet, 7 subjects [3 men, 4 women; 76.1 +/- 5.8 kg, 164.7 +/- 4.4 cm, 30.7 +/- 4.5% body fat, 39.1 +/- 2.8 VO(2max) (maximal oxygen uptake) mL/(kg . min)] participated in 4 wk of aerobic exercise training (running and walking 4-5 times/wk at 65-85% maximal heart rate). WBPTO (determined via constant infusion of 1-[(13)C] leucine), nitrogen balance, and body composition were determined at baseline and after 4 wk of training. Nitrogen balance (-1.0 +/- 0.7 vs. 0.9 +/- 1.1 g N/24 h, P = 0.03) improved with exercise training, whereas body mass and composition did not change. Leucine Ra did not change, Ox decreased [18 +/- 2 to 15 +/- 2 micromol/(kg . h), P </= 0.001], and NOLD tended to increase [128 +/- 18 to 151 +/- 19 micromol/(kg . h), P = 0.09] in response to training. These data indicate improved protein utilization in response to exercise training in weight-stable subjects. This study emphasizes the importance of dietary control, with specific regard to energy and protein intakes, in the characterization of protein utilization in response to an exercise intervention.
运动和膳食蛋白质摄入均会影响全身蛋白质周转（WBPTO）。很少有研究调查有氧运动训练对摄入特定水平蛋白质的未训练个体的WBPTO[亮氨酸出现率（Ra）、氧化率（Ox）和非氧化亮氨酸处置率（NOLD）]的影响。本研究在一项提供0.88 g蛋白质/（kg·d）的对照饮食干预期间，检测了有氧运动训练对未训练男性和女性WBPTO的影响。在对研究饮食进行2周适应后，7名受试者[3名男性，4名女性；体重76.1±5.8 kg，身高164.7±4.4 cm，体脂率30.7±4.5%，最大摄氧量（VO₂max）39.1±2.8 mL/（kg·min）]参与了为期4周的有氧运动训练（每周跑步和步行4 - 5次，心率为最大心率的65 - 85%）。在基线和训练4周后测定WBPTO（通过持续输注1 - [(¹³)C]亮氨酸测定）、氮平衡和身体组成。运动训练使氮平衡得到改善（-1.0±0.7 vs. 0.9±1.1 g N/24 h，P = 0.03），而体重和身体组成未发生变化。亮氨酸Ra未改变，Ox降低[从18±2降至15±2 μmol/（kg·h），P≤0.001]，NOLD有增加趋势[从128±18增至151±19 μmol/（kg·h），P = 0.09]。这些数据表明体重稳定的受试者在运动训练后蛋白质利用率提高。本研究强调了在描述运动干预后蛋白质利用情况时，饮食控制（特别是能量和蛋白质摄入量）的重要性。
