Research on relationships between physical fitness and sleep duration among older adults is scarce, especially in Taiwanese representative samples of elderly people who undergo physical fitness measurements. This study aimed to determine the associations between physical fitness and short and long sleep durations among older adults in Taiwan. We conducted a cross-sectional study and reviewed data derived from the National Physical Fitness Survey in Taiwan. A total of 24,125 Taiwanese adults aged 65 years and older participated in this study between October 2014 and March 2015. Each individual’s sleep duration was recorded with a standard questionnaire method. Sleep duration data were stratified into short (≤5 h), normal (6–7 h), and long (≥8 h) sleep duration groups. Physical fitness was assessed by five components: aerobic endurance (2 min step test), muscle strength and endurance (30 s arm curl and 30 s chair stand tests), flexibility (back scratch and chair sit-and-reach tests), body composition (body mass index (BMI) and waist-to-hip ratio (WHR)), and balance (one-leg stance with eye open and 8-foot up-and-go tests). To understand whether a dose–response relationship exists between physical fitness and short or long sleep duration, we analyzed four levels of performance on the basis of quartiles of physical fitness measurements by using logistic regression. The first quartile of physical fitness performance was the baseline level. The odds ratio (OR) for short sleep duration for the third quartile of BMI was 0.8031 times (95% CI, 0.7119–0.9061) lower than the baseline. For the fourth quartile of BMI, the OR was 0.8660 times (95% CI, 0.7653–0.9800) lower than the baseline. The adjusted OR for long sleep duration significantly decreased in the second, third, and fourth quartiles of the 30 s chair stand, back scratch, chair sit-and-reach test, one-leg stance with one eye open, and BMI. The adjusted OR was increased in the third and fourth quartiles of the 8-foot up-and-go and WHR. The results of the current study suggest that physical fitness performance may influence sleep duration as an associated factor, and the relationship is much stronger for long sleep duration than for short sleep duration.

The present study aimed to investigate the effect of oral resveratrol supplementation on the key molecular gene expressions involved in mitochondria biogenesis and glycogen resynthesis in human skeletal muscle. Nine young male athletes participated in the single-blind and crossover designed study. All subjects completed a 4-day resveratrol and placebo supplement in a randomized order while performing a single bout of cycling exercise. Immediately after the exercise challenge, the subjects consumed a carbohydrate (CHO) meal (2 g CHO/Kg body mass) with either resveratrol or placebo capsules. Biopsied muscle samples, blood samples and expired gas samples were obtained at 0 h and 3 h after exercise. The muscle samples were measured for gene transcription factor expression by real-time PCR for glucose uptake and mitochondria biogenesis. Plasma glucose, insulin, glycerol, non-esterified fatty acid concentrations and respiratory exchange ratio were analyzed during post-exercise recovery periods. The results showed that the muscle glycogen concentrations were higher at 3 h than at 0 h; however, there were no difference between resveratrol trial and placebo trial. There were no significantly different concentrations in plasma parameters between the two trials. Similarly, no measured gene expressions were significant between the two trials. The evidence concluded that the 4-day oral resveratrol supplementation did not improve post-exercise muscle glycogen resynthesis and related glucose uptake and mitochondrial biosynthesis gene expression in men.

Background: The relationship between sleep duration and physical fitness is one aspect of sleep health. Potential factors associated with sleep duration interfere with physical fitness performance, but the impact trends on physical fitness indicators remain unclear. Methods: This study examined associations between sleep duration and physical fitness among young to middle-aged adults in Taiwan. A total of 42,781 Taiwanese adults aged 23–45 participated in the National Physical Fitness Examination Survey 2013 (NPFES-2013) in Taiwan between October 2013 and March 2014. A standardized structural questionnaire was used to record participants’ sleep duration, which was stratified as short (< 6 h/day (h/d)), moderate (6–7 h/d; 7–8 h/d; 8-9 h), and long (≥ 9 h/d) sleep duration groups. Physical fitness was assessed based on four components: body composition (body mass index [BMI], waist-to-height ratio [WHtR], and waist-to-hip ratio [WHR]), muscle strength and endurance (1-min bent-leg sit-up test [BS]), flexibility (sit-and-reach test [SR]), and cardiorespiratory endurance index (3-min step test [CEI]). Results: By using analysis of covariance (ANCOVA), after sex grouping and age adjustment, we observed that sleep duration was significantly associated with obesity, functional fitness, and self-perception of health. The sleep duration for low obesity-related values (BMI, WHtR, and WHR) for men was 7–9 h/d, and that for women was 7–8 h/d. Sleeping more than 8 h/d showed poor functional fitness performances (BS and SR). For both sexes, sleep duration of 8–9 h/d was the optimal sleep duration for self-perceptions of health. Conclusions: Our research found that there were wide and different associations of sleep duration with physical fitness and self-perception of health among Taiwanese adults aged 23–45, and there were differences in these associated manifestations between men and women. This study could be of great importance in regional public health management in Taiwan, and provide inspirations for clinical research on physical fitness.