Bambaeichi E, Reilly T, Cable N T, Giacomoni M
Department of Physical Education, Isfahan University, Iran.
Ergonomics. 2005;48(11-14):1499-511. doi: 10.1080/00140130500101437.
Disrupted sleep is the most common form of sleep deprivation in travellers, shift workers, athletes the night before important competitions and among parents of infants. The influence of partial sleep loss on muscle strength might differ according to the time of testing on the following day. This study was therefore designed to assess the interaction between the effects of partial sleep loss and time of day on muscle strength in females. Eight sedentary eumenorrheic females (mean +/- SD; age 30 +/- 6 years, height 1.62 +/- 0.06 m and body mass 67 +/- 5.0 kg) took part in the study, in a counterbalanced design. Measurements of muscle strength were carried out at 06:00 and 18:00 hours after the one control night (no sleep loss) and the one night of partial sleep loss, during menses. Muscle strength measures included isokinetic (at 1.05, 3.14 rad s(-1); 90 degrees range of motion) and isometric peak torque (at 60 degrees of knee flexion) of knee extensors and flexors (dominant leg). In addition, isometric force of knee extensors with super-imposed electrical twitches (50 Hz, 250 V, 200 mus pulse width) was measured using the same procedure in order to control for motivation. Rectal temperature was measured during the 30 min before muscle strength measurements. Partial sleep loss consisted of allowing 2.5 h sleep (between 03:00 and 05:30 h), whilst in the control condition (no sleep loss) subjects retired between 22:30 and 23:30 h, rising at 05:30 hours. All measurements were conducted at just one phase of the menstrual cycle (menses) to prevent any masking effect due to different phases of the menstrual cycle. In both conditions (with and without partial sleep loss) a diurnal variation was observed in peak torque of knee flexors at 1.05 (F(1,7) = 5.5, p < 0.05) and 3.14 rad s(-1) (F(1,7) = 8.0, p < 0.05); values at 18:00 hours were 4.5 and 5.9% higher than at 06:00 hours, respectively. No significant diurnal variation was observed for the other muscle strength measures. No significant effect of partial sleep loss or interaction effect (sleep x time of day) was observed for muscle strength measures. However, the performance rhythms were in phase with the circadian rhythm in rectal temperature. Partial sleep deprivation over one night did not have any adverse effect on maximal muscle strength, nor on diurnal variations of muscle strength indices. As the effect of time of day was observed with some of the muscle strength measures, it is suggested that, in designing future studies using females, the control of time of day is essential.
睡眠中断是旅行者、轮班工作者、重要比赛前一晚的运动员以及婴儿父母中最常见的睡眠剥夺形式。部分睡眠缺失对肌肉力量的影响可能因次日测试时间的不同而有所差异。因此，本研究旨在评估部分睡眠缺失的影响与一天中的时间对女性肌肉力量的相互作用。八名久坐不动、月经周期正常的女性（平均±标准差；年龄30±6岁，身高1.62±0.06米，体重67±5.0千克）参与了本研究，采用了平衡设计。在一个对照夜（无睡眠缺失）和一个部分睡眠缺失夜之后的06:00和18:00进行肌肉力量测量，测量在月经期间进行。肌肉力量测量包括膝关节伸肌和屈肌（优势腿）的等速肌力（在1.05、3.14弧度/秒；90度运动范围）和等长峰值扭矩（在膝关节屈曲60度时）。此外，使用相同程序测量膝关节伸肌在叠加电刺激（50赫兹，250伏，200微秒脉冲宽度）下的等长力，以控制动机。在肌肉力量测量前30分钟测量直肠温度。部分睡眠缺失包括允许2.5小时睡眠（03:00至05:30之间），而在对照条件下（无睡眠缺失），受试者在22:30至23:30之间就寝，05:30起床。所有测量均在月经周期的一个阶段（月经期）进行，以防止月经周期不同阶段产生任何掩盖效应。在两种条件下（有和没有部分睡眠缺失），观察到膝关节屈肌在1.05弧度/秒（F(1,7)=5.5，p<0.05）和3.14弧度/秒（F(1,7)=8.0，p<0.05）时的峰值扭矩存在日变化；18:00时的值分别比06:00时高4.5%和5.9%。其他肌肉力量测量未观察到显著日变化。对于肌肉力量测量，未观察到部分睡眠缺失的显著影响或交互作用（睡眠×一天中的时间）。然而，性能节律与直肠温度的昼夜节律同步。一晚的部分睡眠剥夺对最大肌肉力量以及肌肉力量指数的日变化均无任何不利影响。由于在一些肌肉力量测量中观察到了一天中时间的影响，建议在设计未来使用女性的研究时，控制一天中的时间至关重要。
