Department of Kinesiology and Sport Sciences, University of Miami, Coral Gables, FL 33146, USA.
Department of Health and Human Performance, Texas State University, San Marcos, TX 78666, USA.
Int J Environ Res Public Health. 2021 May 4;18(9):4890. doi: 10.3390/ijerph18094890.
Recent evidence suggests an innovative approach to muscle conditioning: focal knee joint cooling (FKJC) appears to improve quadriceps function, including static (isometric) strength. However, there is limited evidence on the effects of FKJC on dynamic (concentric and eccentric) strength. Thus, the purpose of the study was to examine dynamic quadriceps strength following FKJC as well as static strength. Twenty-one college-aged participants volunteered. They randomly underwent 20 min of FKJC and control condition at least 72 h apart. FKJC involves two ice bags, placed on the anterior and posterior surfaces of the knee, whereas the control condition received a plastic ice bag filled with candy corn. We assessed isometric and isokinetic (concentric and eccentric) quadriceps strength at two different velocities (60°/s and 180°/s). Participants performed three maximal voluntary contractions for each mode of muscle contraction, before and after each treatment (immediately, 20, and 40 min after). The outcome variable was maximum knee extension peak torque. FKJC did not change peak torque during any mode of muscle contraction ( > 0.05). The current findings suggest that 20 min of FKJC does not change static (isometric) or dynamic (isokinetic) strength of the quadriceps. FKJC was neither beneficial nor harmful to static or dynamic muscular strength.
最近的证据表明，一种创新的肌肉训练方法：膝关节焦点冷却（FKJC）似乎可以改善股四头肌功能，包括静态（等长）力量。然而，关于 FKJC 对动态（向心和离心）力量的影响的证据有限。因此，本研究的目的是研究 FKJC 对股四头肌动态力量以及静态力量的影响。21 名大学生志愿者参与了研究。他们至少在 72 小时后随机接受 FKJC 和对照条件 20 分钟。FKJC 包括两个冰袋，分别放置在膝关节的前后面，而对照条件则接受一个装满玉米糖的塑料冰袋。我们评估了两种不同速度（60°/s 和 180°/s）下的等长和等速（向心和离心）股四头肌力量。在每种肌肉收缩模式下，参与者在每种治疗前后（立即、20 分钟和 40 分钟后）进行三次最大自主收缩。因变量是最大膝关节伸展峰值扭矩。FKJC 没有改变任何肌肉收缩模式下的峰值扭矩（> 0.05）。目前的研究结果表明，20 分钟的 FKJC 不会改变股四头肌的静态（等长）或动态（等速）力量。FKJC 对静态或动态肌肉力量既没有益处也没有害处。
