Pollock M L, Leggett S H, Graves J E, Jones A, Fulton M, Cirulli J
Center for Exercise Science, College of Medicine, University of Florida, Gainesville 32610.
Am J Sports Med. 1989 Sep-Oct;17(5):624-9. doi: 10.1177/036354658901700506.
Development of a new testing machine, which stabilizes the pelvis, allowed us to evaluate the lumbar extensor muscles before and after training. Fifteen healthy subjects (29.1 +/- 8 years of age) trained 1 day per week for 10 weeks and 10 healthy subjects (33.7 +/- 16 years of age) acted as controls. Training consisted of 6 to 15 repetitions of full range of motion variable resistance lumbar extension exercise to volitional fatigue and periodic maximal isometric contractions taken at seven angles through a full range of motion. Before and after the 10 week training period, subjects completed a maximum isometric strength test at seven angles through a 72 degrees range of motion (0 degrees, 12 degrees, 24 degrees, 36 degrees, 48 degrees, 60 degrees, and 72 degrees of lumbar flexion). The training group significantly improved in lumbar extension strength at all angles (P less than or equal to 0.01). The result at 0 degrees (full extension) showed an increase from 180.0 +/- 25 Nm to 364.1 +/- 43 Nm (+102%) and at 72 degrees (full flexion) from 427.4 +/- 44.1 to 607.4 +/- 68 (+42%) Nm. Results from the control group showed no change (P greater than or equal to 0.05). The magnitude of gain shown by the training group reflects the low initial trained state of the lumbar extensor muscles. These data indicate that when the lumbar area is isolated through pelvic stabilization, the isolated lumbar extensor muscles show an abnormally large potential for strength increase.
一种新型测试机器的研发使得骨盆得以稳定，这让我们能够在训练前后对腰伸肌进行评估。15名健康受试者（年龄29.1±8岁）每周训练1天，共训练10周，10名健康受试者（年龄33.7±16岁）作为对照组。训练包括6至15次全范围运动的可变阻力腰椎伸展运动，直至自觉疲劳，并在全范围运动的七个角度进行周期性最大等长收缩。在为期10周的训练期前后，受试者在72度的运动范围内（腰椎前屈0度、12度、24度、36度、48度、60度和72度）的七个角度完成最大等长力量测试。训练组在所有角度的腰椎伸展力量均有显著提高（P≤0.01）。0度（完全伸展）时的结果显示，力量从180.0±25牛顿米增加到364.1±43牛顿米（增加102%），72度（完全前屈）时从427.4±44.1增加到607.4±68（增加42%）牛顿米。对照组的结果无变化（P≥0.05）。训练组显示的力量增加幅度反映了腰伸肌初始训练状态较低。这些数据表明，当通过骨盆稳定来孤立腰椎区域时，孤立的腰伸肌显示出异常大的力量增加潜力。
