Department of Health and Kinesiology, Purdue University , West Lafayette, Indiana.
Department of Animal Sciences, Purdue University , West Lafayette, Indiana.
J Appl Physiol (1985). 2019 Apr 1;126(4):965-976. doi: 10.1152/japplphysiol.00910.2018. Epub 2019 Jan 3.
The purpose of this study was to investigate the effects of heat therapy (HT) on functional recovery, the skeletal muscle expression of angiogenic factors, macrophage content, and capillarization after eccentric exercise in humans. Eleven untrained individuals (23.8 ± 0.6 yr) performed 300 bilateral maximal eccentric contractions of the knee extensors. One randomly selected thigh was treated with five daily 90-min sessions of HT, whereas the opposite thigh received a thermoneutral intervention. Peak isokinetic torque of the knee extensors was assessed at baseline and daily for 4 days and fatigue resistance was assessed at baseline and 1 and 4 days after the eccentric exercise session. Muscle biopsies were obtained 2 wk before and 1 and 5 days after the eccentric exercise bout. There were no differences between thighs in the overall recovery profile of peak torque. However, the thigh exposed to HT had greater fatigue resistance than the thigh exposed to the thermoneutral intervention. The change from baseline in mRNA expression of vascular endothelial growth factor (VEGF) was higher at day 1 in the thigh exposed to HT. Protein levels of VEGF and angiopoietin 1 were also significantly higher in the thigh treated with HT. The number of capillaries around type II fibers decreased similarly in both thighs at day 5. Exposure to HT had no impact on macrophage content. These results suggest that HT accelerates the recovery of fatigue resistance after eccentric exercise and promotes the expression of angiogenic factors in human skeletal muscle. NEW & NOTEWORTHY We investigated whether exposure to local heat therapy (HT) accelerates recovery after a bout of eccentric exercise in humans. Compared with a thermoneutral control intervention, HT improved fatigue resistance of the knee extensors and enhanced the expression of the angiogenic mediators vascular endothelial growth factor and angiopoietin 1. These results suggest that HT hastens functional recovery and enhances the expression of regulatory factors involved in muscle repair after eccentric exercise in humans.
本研究旨在探讨热疗（HT）对人体离心运动后功能恢复、血管生成因子的骨骼肌表达、巨噬细胞含量和毛细血管化的影响。11 名未经训练的个体（23.8±0.6 岁）进行了 300 次双侧最大离心伸膝运动。一条随机选定的大腿接受了 5 天 90 分钟的 HT 治疗，而对侧大腿接受了常温干预。在基线和每天进行 4 天评估了膝关节伸肌的最大等速扭矩，并在基线和离心运动后 1 天和 4 天评估了疲劳抵抗。在离心运动前后 2 周和 1 天和 5 天分别采集肌肉活检。在整个峰值扭矩恢复过程中，两条大腿之间没有差异。然而，接受 HT 的大腿比接受常温干预的大腿具有更强的抗疲劳能力。在接受 HT 的大腿中，血管内皮生长因子（VEGF）的 mRNA 表达从基线的变化在第 1 天更高。接受 HT 治疗的大腿中 VEGF 和血管生成素 1 的蛋白水平也显著升高。在第 5 天，两条大腿中 II 型纤维周围的毛细血管数量都相似地减少。巨噬细胞含量不受 HT 暴露的影响。这些结果表明，HT 可加速离心运动后疲劳抵抗的恢复，并促进人骨骼肌中血管生成因子的表达。新的和值得注意的是：我们研究了暴露于局部热疗（HT）是否能加速人类一次离心运动后的恢复。与常温对照干预相比，HT 提高了膝关节伸肌的抗疲劳能力，并增强了血管生成介质血管内皮生长因子和血管生成素 1 的表达。这些结果表明，HT 可加速人类离心运动后功能恢复，并增强与离心运动后肌肉修复相关的调节因子的表达。
