Objectives In this study, we investigated daily fluctuations in molecular (gene expression) and physiological (biomechanical muscle properties) features in human peripheral cells and their correlation with exercise performance. Methods 21 healthy participants (13 men and 8 women) took part in three test series: for the molecular analysis, 15 participants provided hair, blood or saliva time-course sampling for the rhythmicity analysis of core-clock gene expression via RT-PCR. For the exercise tests, 16 participants conducted strength and endurance exercises at different times of the day (9h, 12h, 15h and 18h). Myotonometry was carried out using a digital palpation device (MyotonPRO), five muscles were measured in 11 participants. A computational analysis was performed to relate core-clock gene expression, resting muscle tone and exercise performance. Results Core-clock genes show daily fluctuations in expression in all biological samples tested for all participants. Exercise performance peaks in the late afternoon (15–18 hours for both men and women) and shows variations in performance, depending on the type of exercise (eg, strength vs endurance). Muscle tone varies across the day and higher muscle tone correlates with better performance. Molecular daily profiles correlate with daily variation in exercise performance. Conclusion Training programmes can profit from these findings to increase efficiency and fine-tune timing of training sessions based on the individual molecular data. Our results can benefit both professional athletes, where a fraction of seconds may allow for a gold medal, and rehabilitation in clinical settings to increase therapy efficacy and reduce recovery times.

中文翻译：

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核心时钟基因表达的日变化与静息肌肉特性相关，并预测全天运动表现的波动

目的在这项研究中，我们调查了人类外周细胞中分子（基因表达）和生理（生物力学肌肉特性）特征的每日波动及其与运动表现的关系。方法21名健康参与者（13名男性和8名女性）参加了三个测试系列：分子分析，15名参与者提供了头发，血液或唾液时程采样，以通过RT-PCR进行核心时钟基因表达的节奏分析。对于运动测试，有16位参与者在一天的不同时间（9h，12h，15h和18h）进行了力量和耐力锻炼。使用数字触诊设备（MyotonPRO）进行肌张力测定，在11位参与者中测量了5条肌肉。进行了计算分析以关联核心时钟基因表达，静息肌张力和运动表现。结果核心时钟基因显示在所有参与者测试的所有生物样品中表达的每日波动。运动表现在下午晚些时候达到高峰（男性和女性均为15-18小时），并且表现出不同的运动能力，具体取决于运动的类型（例如，力量与耐力）。一天中的肌肉张力各不相同，较高的肌肉张力与更好的表现相关。分子日分布与运动表现的日变化相关。结论培训计划可以从这些发现中受益，从而可以基于单个分子数据来提高效率和调整培训课程的时机。我们的成绩可以使两名职业运动员受益，因为几秒钟的时间可以赢得金牌，