Date Published: March 30, 2017
Publisher: Public Library of Science
Author(s): Liyuan Fu, Liye Jia, Wen Zhang, Peipei Han, Li Kang, Yixuan Ma, Hairui Yu, Tianqi Zhai, Xiaoyu Chen, Qi Guo, Yiqing Song.
Physical performance is an important healthy factor in elder people. Good living habits, which include sleep, can maintain physical strength and physical performance. The aim of the present study was to conduct a cross-sectional study to determine the association between total sleep duration and physical performance.
Our study population comprised residents of the township central hospital in the suburban of Tianjin, China. We measured muscle strength, walk speed and balance function by grip, 4-m walk test and timed up and go test (TUGT). We divided sleep duration into four groups <7h, 7-8h, >8-9h, >9h.
A total 898 participants had completed data (392 men and 506 women, mean age 67.71 years). In man, adjusted sleep duration was associated with lower grip in > 9 h group, the mean value (95% CI) was 0.429 (0.409, 0.448), and longer TUGT time was also associated with long sleep duration, 10.46s (9.97 s, 10.95 s). In women, adjusted slower 4-m walk speed present an inverse U-shaped relation with sleep duration, by 0.93 m/s (0.86 m/s, 0.98 m/s), 0.97 m/s (0.96 m/s, 1.00 m/s), 0.97 m/s (0.95 m/s, 0.99 m/s) and 0.92 m/s (0.89 m/s, 0.96 m/s); longer TUGT time were associated with long sleep duration (> 9 h), by 11.23 s (10.70 s, 11.77 s).
In Chinese community-dwelling elderly, lower muscle strength and lower balance function were associated with long sleep duration in men. Slower walk speed and lower balance function were associated with long sleep duration in women.
Physical performance is an important healthy factor in elder people. As the growth of the age, physical performance such as balance, walk speed, muscle strength diminished , leading to high risks of falls and subsequent fractures, even lose independence, increase morbidity and mortality rates [2–4]. Thus, it is essential to improve or prevent the factors of physical performance decline in elderly at once. Good living habits, which may be one of ways to solve this problem, had been paid more and more attention by the human beings. While in recent years, as an important component of living habits, sleep is becoming a significant problem for elder people.
Our findings suggest a difference relationship between sleep duration and physical performance in men and women. We adjusted the age, widow, live alone, diabetes, cardiovascular risk, falls, skeletal muscle mass, sleep quality and sleep drug long sleep duration was best associated with slower walk speed, longer TUGT in women and longer TUGT, lower grip in men. We found that there might be contrary relation between long sleep duration and balance function (measured by TUGT) in both men and women. This is an important finding because poor physical performance always accompany high risk of morbidity and mortality of disease [3, 4]. To our knowledge, this is the first studies to explore the different relationship in sleep duration and physical performance by gender variance in Chinese community-dwelling elderly.
Our study found that lower grip was associated with long sleep duration in men, and walk speed and lower balance were associated with long sleep duration in women. Given the prevalence of long sleep duration in older adults, our findings suggest that interventions of sleep may reduce physical functional decline among the rising population of older adults. Future research with cohort study should test whether long sleep durations are causally associated with functional decline and the effect that intervention of sleep on physical performance among community-dwelling older adults.