Institute of Human Performance and Rehabilitation, Center for Research and Technology-Thessaly, Trikala, Greece.
Med Sci Sports Exerc. 2011 Jan;43(1):64-73. doi: 10.1249/MSS.0b013e3181e91d90.
The effects of chronic eccentric-only versus concentric-only exercise on muscle physiology and blood biochemistry were investigated.
Twenty women performed on an isokinetic dynamometer a concentric (n = 10;mean ± SEM: age = 21.0 ± 0.4 yr, body fat = 22.0% ± 0.9%) or an eccentric (n = 10, age = 20.0 ± 0.3 yr, body fat = 23.2% ± 0.7%) exercise session using the knee extensors of both lower limbs once a week for eight subsequent weeks. Muscle function (isometric, concentric, and eccentric peak torque, range of movement, and soreness) was evaluated before, immediately after, and 48 h postexercise in each one of the eight training weeks. Body fat, resting energy expenditure (REE), lipid, and carbohydrate oxidation rate as well as blood chemistry measurements (lipid, lipoprotein and apolipoprotein profile, glucose, insulin, glycosylated hemoglobin, and creatine kinase) were examined before and 48 h postexercise at the first and eighth week of training.
Acute eccentric exercise increased REE and fat oxidation at week 1 (12.7% and 12.9%, respectively) and at week 8 (0.7% and 2.8%, respectively). Chronic eccentric exercise increased resting REE and fat oxidation at week 8 compared with week 1 (5.0% and 9.9%, respectively). Acute eccentric exercise improved blood lipid profile at week 1 and week 8. Chronic eccentric exercise improved resting blood lipid profile at week 8. Acute eccentric exercise increased insulin resistance at week 1 but not at week 8. Chronic eccentric exercise decreased resting insulin resistance at week 8.
It is reported for the first time that only 30 min of eccentric exercise per week for 8 wk was sufficient to improve health risk factors.
研究慢性离心运动与向心运动对肌肉生理学和血液生化学的影响。
20 名女性在等速测力机上进行了一次向心（n = 10；平均 ± SEM：年龄 = 21.0 ± 0.4 岁，体脂 = 22.0% ± 0.9%）或离心（n = 10，年龄 = 20.0 ± 0.3 岁，体脂 = 23.2% ± 0.7%）运动，每周一次，共 8 周。在每周的 8 次训练中，在每次运动前、运动后即刻和运动后 48 小时评估肌肉功能（等长、向心和离心峰值扭矩、运动范围和酸痛感）。在训练的第 1 周和第 8 周，在运动前和运动后 48 小时检查体脂、静息能量消耗（REE）、脂质和碳水化合物氧化率以及血液化学测量值（脂质、脂蛋白和载脂蛋白谱、葡萄糖、胰岛素、糖化血红蛋白和肌酸激酶）。
急性离心运动在第 1 周（分别为 12.7%和 12.9%）和第 8 周（分别为 0.7%和 2.8%）增加了 REE 和脂肪氧化。慢性离心运动在第 8 周比第 1 周增加了静息 REE 和脂肪氧化（分别为 5.0%和 9.9%）。急性离心运动在第 1 周和第 8 周改善了血液脂质谱。慢性离心运动在第 8 周改善了静息血液脂质谱。急性离心运动在第 1 周增加了胰岛素抵抗，但在第 8 周没有增加。慢性离心运动在第 8 周降低了静息胰岛素抵抗。
据报道，每周仅进行 30 分钟的离心运动，持续 8 周，就足以改善健康风险因素。
