Braith R W, Graves J E, Pollock M L, Leggett S L, Carpenter D M, Colvin A B
Center for Exercise Science, College of Medicine, University of Florida, Gainesville 32611.
Int J Sports Med. 1989 Dec;10(6):450-4. doi: 10.1055/s-2007-1024942.
The purpose of this study was to evaluate the effectiveness of resistance training performed either 2 days/week or 3 days/week. One hundred and seventeen sedentary volunteers were randomly assigned to one of the two training groups or a control group. Twenty-two men (27 +/- 5 years) and 22 women (26 +/- 5 years) trained for 10 weeks. Twenty-five men (26 +/- 5 years) and 22 women (24 +/- 5 years) trained for 18 weeks. Twenty-six subjects served as controls and did not train. Training consisted of a single set of variable resistance bilateral knee extensions performed to volitional fatigue with a weight load that allowed seven to ten repetitions. Prior to and immediately following training, isometric strength was evaluated at 70, 85, 100, 115, 130, 145, 160, and 171 degrees of knee extension with a Nautilus knee extension tensiometer. All groups who trained showed a significant increase in peak isometric strength when compared with controls (P less than 0.01). Groups that trained 3 days/week increased peak isometric strength (10 weeks = 21.2%; 18 weeks = 28.4%) to a greater extent (P less than 0.05) than groups that trained 2 days/week (10 weeks = 13.5%; 18 weeks = 20.9%). We conclude that resistance training 2 days/week significantly improves knee extension isometric strength; however, the magnitude of strength gain is greater when training is performed 3 days/week. These data indicate that the adult exerciser (18 to 38 years) training 2 days/week may derive approximately 80% of the isometric strength benefits achieved by those training 3 days/week.
本研究的目的是评估每周进行2天或3天抗阻训练的效果。117名久坐不动的志愿者被随机分配到两个训练组之一或一个对照组。22名男性（27±5岁）和22名女性（26±5岁）进行了10周的训练。25名男性（26±5岁）和22名女性（24±5岁）进行了18周的训练。26名受试者作为对照组，不进行训练。训练包括一组可变阻力的双侧膝关节伸展运动，进行至意志疲劳，重量负荷允许进行7至10次重复。在训练前和训练后立即，使用诺德士膝关节伸展张力计在膝关节伸展70、85、100、115、130、145、160和171度时评估等长力量。与对照组相比，所有训练组的等长力量峰值均显著增加（P<0.01）。每周训练3天的组比每周训练2天的组在更大程度上增加了等长力量峰值（10周 = 21.2%；18周 = 28.4%）（P<0.05）（10周 = 13.5%；18周 = 20.9%）。我们得出结论，每周2天的抗阻训练能显著提高膝关节伸展等长力量；然而，每周训练3天时力量增加的幅度更大。这些数据表明，每周训练2天的成年锻炼者（18至38岁）可能获得每周训练3天者所获得的等长力量益处的约80%。
