Background Musculoskeletal disease has become an important public health problem with an aging population. Studies on muscle mass and body fat rate are largely conducted among elderly people rather than in general adult residents.
Objective This study investigates the muscle mass and body fat rate of adult residents in Shanghai, and their potential influencing factors.
Methods Using the method of stratified random sampling, six districts were randomly selected in Shanghai in 2015 according to their economic and geographical conditions, namely Huangpu District, Putuo District, Xuhui District, Yangpu District, Songjiang District, and Jiading District. Four sub-districts in each district and 20 households in each sub-district were randomly selected, and all the members of a selected household aged 18 years and above were investigated. The investigation included personal general information questionnaire survey, 3-day 24-hour dietary survey, and anthropological indicators. The intakes of cereal, livestock, aquatic products, eggs, milk, and legumes was calculated, and the height, weight, body mass index (BMI), muscle mass, and body fat rate were measured directly.
Results A total of 1 009 residents were investigated, including 471 males, median 58.52 years, and 538 females, median 57.63 years. The medians of whole body muscle mass of men aged 18-44, 45-59, and ≥ 60 years were 51.00, 50.20, and 48.50 kg, respectively, and their medians of body fat rate were 23.40%, 24.40%, and 24.90%, respectively; the medians of whole body muscle mass of women aged 18-44, 45-59, and ≥ 60 years were 36.60, 37.60, and 36.10 kg, respectively, and their medians of body fat rate were 30.35%, 34.30%, and 35.60%, respectively; the whole body muscle mass of males was higher than that of females in all age groups (P < 0.001), and the body fat rate was lower (P < 0.001). Multiple linear regression analysis results showed that male (b'=0.748, P < 0.001), higher BMI (b'=0.347, P < 0.001), younger age (b'=-0.216, P < 0.001), and regular physical exercise (b'=0.045, P=0.017) were associated with higher whole body muscle mass; female (b'=-0.705, P < 0.001), higher BMI (b'=0.622, P < 0.001), older age (b'=0.061, P=0.001), smokers (b'=0.060, P=0.005), and higher legume intake (b'=0.055, P=0.002) were associated with higher body fat rate.
Conclusion With the increase of age, adult residents in Shanghai show decreasing whole body muscle mass and increasing body fat rate. Regular physical exercise could be an effective measure to slow sarcopenia. Smokers should pay more attention to potential reduction in body fat rate.
DownLoad: