Herman-Montemayor Jennifer R, Hikida Robert S, Staron Robert S
1Department of Biomedical Sciences, College of Osteopathic Medicine, Rocky Vista University, Parker, Colorado; and 2Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio.
J Strength Cond Res. 2015 Nov;29(11):3105-14. doi: 10.1519/JSC.0000000000000925.
The purpose of this investigation was to identify adaptations in satellite cell (SC) content and myonuclear domain (MND) after 6-week slow-speed vs. "normal-speed" resistance training programs. Thirty-four untrained females were divided into slow speed (SS), traditional strength (TS), traditional muscular endurance (TE), and nontraining control (C) groups. Three sets each of leg press, squat, and knee extension were performed 2 days per week for the first week and 3 days per week for the following 5 weeks. The SS group performed 6-10 repetition maximum (6-10RM) for each set with 10-second concentric (con) and 4-second eccentric (ecc) contractions for each repetition. Traditional strength and TE performed 6-10RM and 20-30RM, respectively, at "normal" speed (1-2 seconds per con and ecc contractions). Traditional muscular endurance and SS trained at the same intensity (40-60% 1RM), whereas TS trained at 80-85% 1RM. Pretraining and posttraining muscle biopsies were analyzed for fiber cross-sectional area, fiber type, SC content, myonuclear number, and MND. Satellite cell content of type I, IIA, IIAX, and IIX fibers significantly increased in TS. However, SC content of only type IIAX and IIX fibers increased in SS, and there was no change in TE or C. Myonuclear number did not change in any group. Myonuclear domain of type I, IIA, IIAX, and IIX fibers increased in TS, whereas MND of only type IIA fibers increased in SS, and there was no change in TE or C. In conclusion, slow-speed resistance training increased SC content and MND more than training with a similar resistance at normal speed. However, high-intensity normal-speed training produced the greatest degree of fiber adaptation for each variable.
本研究的目的是确定在进行为期6周的低速与“正常速度”抗阻训练计划后，卫星细胞（SC）含量和肌核域（MND）的适应性变化。34名未经训练的女性被分为低速组（SS）、传统力量组（TS）、传统肌肉耐力组（TE）和非训练对照组（C）。在第一周，每周进行2天的腿举、深蹲和伸膝练习，每组3组；在接下来的5周，每周进行3天。SS组每组进行6 - 10次最大重复量（6 - 10RM），每次重复进行10秒的向心收缩（con）和4秒的离心收缩（ecc）。传统力量组和TE组分别以“正常”速度（每次向心和离心收缩1 - 2秒）进行6 - 10RM和20 - 30RM的练习。传统肌肉耐力组和SS组以相同强度（40 - 60% 1RM）训练，而TS组以80 - 85% 1RM训练。对训练前和训练后的肌肉活检样本进行分析，以测定肌纤维横截面积、肌纤维类型、SC含量、肌核数量和MND。TS组中I型、IIA型、IIAX型和IIX型肌纤维的卫星细胞含量显著增加。然而，SS组中仅IIAX型和IIX型肌纤维的SC含量增加，TE组和C组则无变化。所有组的肌核数量均未改变。TS组中I型、IIA型、IIAX型和IIX型肌纤维的肌核域增加，而SS组中仅IIA型肌纤维的MND增加，TE组和C组则无变化。总之，与以正常速度进行类似抗阻训练相比，低速抗阻训练使SC含量和MND增加得更多。然而，高强度正常速度训练对每个变量产生的肌纤维适应性程度最大。
