Ogita F, Stam R P, Tazawa H O, Toussaint H M, Hollander A P
Swimming Performance Laboratory, National Institute of Fitness and Sports, Kanoya, Kagoshima, Japan.
Med Sci Sports Exerc. 2000 Oct;32(10):1737-42. doi: 10.1097/00005768-200010000-00012.
The purpose of this study was to determine the primary factors causing the differential oxygen uptake (VO2) response at submaximal intensities between one-legged and two-legged exercise, and whether peak oxygen uptake (VO2peak) increases in proportion to the increase in active muscle mass.
Two different types of exercise were used for this experiment, each requiring a different movement, a different method of stabilizing posture, and, finally, a different limiting VO2peak. In experiment 1, nine male subjects performed one-legged cycling (OLC) and two-legged cycling exercise (TLC) at a pedaling rate of 80 rpm. The exercise intensity was first set at 80 W and was increased by 40 W every 3 min until exhaustion. In experiment 2, six healthy male subjects performed one-legged knee-extension (OKE) and two-legged knee-extension (TKE) exercise at a rate of 50 contractions per minute. The knee-extension exercise was done at constant work rates for a 3-min session in OKE or a 4-min session in TKE. The exercise bouts were performed intermittently at four to seven different submaximal intensities and VO2 was determined at each intensity in all exercises.
At submaximal intensities, VO2 in relation to work rate of one-legged exercise was more steep than those of two-legged exercise, and the mean values of VO2 were significantly higher in one-legged exercise than those in two-legged exercise in both knee extension and cycling exercise. Mean values of VO2peak for two-legged exercise were significantly higher than that for one-legged exercise (P < 0.01); however, it was much lower than two times of that for one-legged exercise even in knee extension exercise where the VO2peak would be limited peripherally.
The findings of this study suggest that the differential VO2 response between one-legged and two-legged exercise would be attributed not only to the difference in force application throughout the exercise movement and to the effect of a postural component but also to the inhibited circulatory response caused by the multiple limb exercise. In addition, it was supposed that VO2peak does not increase in proportion to the exercising muscle mass even during smaller muscle activity where the cardiac pumping capacity has not reached its upper limit.
本研究旨在确定导致单腿和双腿运动在次最大强度下摄氧量（VO₂）反应差异的主要因素，以及最大摄氧量（VO₂peak）是否与活动肌肉量的增加成比例增加。
本实验采用两种不同类型的运动，每种运动需要不同的动作、不同的姿势稳定方法，最后，具有不同的限制VO₂peak。在实验1中，9名男性受试者以80转/分钟的蹬踏频率进行单腿骑行（OLC）和双腿骑行运动（TLC）。运动强度首先设定为80W，每3分钟增加40W，直至疲劳。在实验2中，6名健康男性受试者以每分钟50次收缩的速率进行单腿伸膝（OKE）和双腿伸膝（TKE）运动。在OKE中，伸膝运动以恒定工作率进行3分钟，在TKE中进行4分钟。运动回合在四到七个不同的次最大强度下间歇进行，并在所有运动的每个强度下测定VO₂。
在次最大强度下，单腿运动的VO₂与工作率的关系比双腿运动更陡峭，并且在伸膝和骑行运动中，单腿运动的VO₂平均值显著高于双腿运动。双腿运动的VO₂peak平均值显著高于单腿运动（P < 0.01）；然而，即使在VO₂peak受外周限制的伸膝运动中，它也远低于单腿运动的两倍。
本研究结果表明，单腿和双腿运动之间VO₂反应的差异不仅归因于整个运动过程中力的施加差异和姿势成分的影响，还归因于多肢体运动引起的循环反应抑制。此外，据推测，即使在心脏泵血能力尚未达到上限的较小肌肉活动期间，VO₂peak也不会与运动肌肉量成比例增加。
