Department of Health, Human Performance, and Recreation, Baylor University , Waco, TX 76798, USA.
J Sports Sci Med. 2004 Dec 1;3(4):226-33. eCollection 2004 Dec.
The present study determined the effects of concentric and eccentric muscle actions on the contents of serum myostatin and follistatin-like related gene (FLRG). Eight untrained males performed one exercise bout with each leg, separated by three weeks. One bout consisted of 7 sets of 10 repetitions of eccentric muscle actions of the knee extensors at 150% of the concentric 1-RM while the other bout consisted of 7 sets of 10 repetitions of concentric muscle actions at 75% 1-RM. The legs used and the bouts performed were randomized. Five days prior to each exercise bout, baseline measurements were taken for muscle strength. For both bouts, a venous blood sample was obtained immediately prior to exercise and again at 6, 24, and 48 hr post-exercise. Data were analyzed with 2 X 4 (bout x test) ANOVA (p < 0.05). Increases in serum myostatin and FLRG occurred with each exercise bout and, excluding 48 hr post-exercise, were significantly correlated to one another (p < 0.05). After eccentric exercise, peak increases of 68% and 50% (p < 0.05) were observed for myostatin and FLRG, respectively. Similar increases of 54% and 44% (p < 0.05) were observed after concentric muscle actions. There was no significant difference in expression of myostatin or FLRG as a function of muscle action type. Our results suggest that a single bout of exercise with either eccentric or concentric muscle actions appear to elicit a similar increase in serum myostatin and FLRG. Therefore, the type of muscle action may not be as much a mitigating factor for increasing serum myostatin and FLRG rather than the muscle action per se. Key PointsEccentric muscle actions do not preferentially increase serum myostatin.Increases in serum myostatin in response to eccentric muscle actions are associated with increase in serum FLRG.Increases in serum myostatin and FLRG in response to eccentric muscle actions are not correlated to serum cortisol.
本研究旨在确定向心性和离心性肌肉活动对血清肌肉生长抑制素和卵泡抑素样相关基因（FLRG）含量的影响。8 名未经训练的男性，每条腿分别进行一次运动，间隔 3 周。一组运动由 7 组 150%的最大向心重复次数的离心性膝关节伸展运动组成，另一组由 7 组 75%的最大向心重复次数的向心性运动组成。使用的腿部和进行的运动都是随机的。在每次运动前 5 天，测量肌肉力量的基线值。对于这两种运动，运动前即刻和运动后 6、24 和 48 小时分别抽取静脉血样。采用 2X4（运动类型 X 测试）方差分析（p＜0.05）进行数据分析。两种运动类型后，血清肌肉生长抑制素和 FLRG 均增加，且除运动后 48 小时外，两者呈显著相关（p＜0.05）。离心运动后，肌肉生长抑制素和 FLRG 的峰值分别增加 68%和 50%（p＜0.05）。向心性肌肉活动后，分别观察到 54%和 44%的相似增加（p＜0.05）。肌肉生长抑制素或 FLRG 的表达没有因肌肉活动类型而出现显著差异。我们的研究结果表明，单次离心或向心性运动似乎都能引起血清肌肉生长抑制素和 FLRG 的相似增加。因此，肌肉活动类型可能不是增加血清肌肉生长抑制素和 FLRG 的主要因素，而肌肉活动本身可能是主要因素。关键点离心性肌肉活动不会优先增加血清肌肉生长抑制素。对离心性肌肉活动的反应中血清肌肉生长抑制素的增加与血清 FLRG 的增加相关。对离心性肌肉活动的反应中血清肌肉生长抑制素和 FLRG 的增加与血清皮质醇无关。
