Abstract
Sarcopenia, a growing public health concern lacking targeted therapies, highlights the need to investigate modifiable factors like physical activity (PA) and sedentary behavior, which influence muscle health. However, most research focuses on older adults, with limited data on young and middle-aged populations. This study leverages the National Health and Nutrition Examination Survey (NHANES) data to investigate this topic in the US population aged 18 to 59 to address this critical gap. This cross-sectional study utilized data from 7869 participants in the NHANES (2011-2018) to assess associations between PA patterns, sedentary behavior, and sarcopenia risk. PA and sedentary behavior were measured via self-report, "weekend warriors" was defined as individuals who meet weekly physical activity guidelines (≥150 minutes) but exercise infrequently (<2 sessions/week), and sarcopenia was defined using the Foundation for the National Institutes of Health (FNIH) guidelines. Weighted multivariate logistic regression was used, with results presented as odds ratios (ORs) with 95% confidence intervals (CIs). Nonlinear associations were explored using restricted cubic splines. In the final analysis, 689 participants (8.76%) were classified as having sarcopenia. After adjusting the covariates, sedentary time (h/day) increased the risk of sarcopenia (OR = 1.05, 95% CI: 1.01-1.10), with a linear dose-response relationship. However, for every 1-hour increment in PA, there was a 6% reduction in the risk of sarcopenia (a linear relationship was also observed), and this negative association was more pronounced for vigorous PA (OR = 0.39, 95% CI: 0.29-0.53). Meanwhile, compared to inactive individuals, both "weekend warriors" (OR = 0.41, 95% CI: 0.23-0.72) and those with regular PA patterns (OR = 0.71, 95% CI: 0.54-0.92) were less susceptible to sarcopenia. These associations showed a potentially more significant trend in older (45-59 years) and male participants. This study identifies that PA can decrease the potential risk of sarcopenia in adults aged 18 to 59, whereas prolonged sedentary behavior increases it. Promoting population-level PA participation could serve as a preventive strategy for sarcopenia, however, additional research is necessary to confirm these findings.