Dose-response relationship between weekly physical activity level and the frequency of colds in Chinese middle-aged and elderly individuals

Abstract

Background Engaging in appropriate physical activity can significantly lower the risk of various diseases among middle-aged and older adults. Investigating optimal levels of physical activity (PA) is crucial for enhancing the health of this demographic. This study aims to explore the dose–response relationship between weekly PA levels and the frequency of colds among Chinese middle-aged and elderly individuals, identifying the necessary PA level to effectively diminish the risk of colds. Methods We conducted a cross-sectional study using a web-based survey targeting individuals aged 40 and older (n = 1, 683) in China. The survey collected information on PA and the frequency of colds. Data was analyzed using Kruskal–Wallis test and the χ2 test. We explored the dose–response relationship between weekly PA and cold frequency over the past year through an ordered multivariate logistic regression model and a restricted cubic spline model. Results (1) Brisk walking emerged as the preferred physical exercise for those over 40. The findings suggest that engaging in moderate (odds ratio (OR) = 0.64, P < 0.001, 95% confidence interval (CI) [0.50–0.81]) and high (OR = 0.64, P < 0.001, 95% CI [0.51–0.79]) levels of PA weekly significantly reduces the risk of catching a cold. Individuals with one (OR = 1.47, P < 0.001, 95% CI [1.20–1.80]) or multiple chronic diseases (OR = 1.56, P < 0.001, 95% CI [1.21–2.00]) were at increased risk. Those residing in central (OR = 1.64, P < 0.001, 95% CI [1.33–02.01]) and western China (OR = 1.49, P = 0.008, 95% CI [1.11–02.00]) faced a higher risk compared to their counterparts in eastern China. (2) According to the restricted cubic spline model, adults who experienced one cold in the past year had a weekly PA level of 537.29 metabolic equivalent-minutes per week (MET-min/wk) with an OR value of 1. For those reporting two or more colds, the PA level was 537.76 MET-min/wk with an OR of 1. Conclusions (1) Brisk walking is the most favored exercise among the Chinese middle-aged and elderly, with the prevalence of colds being affected by the number of chronic diseases and the geographic location. (2) Regular, moderate exercise is linked to a lower risk of colds. To effectively reduce cold frequency, it is recommended that middle-aged and elderly Chinese individuals engage in a minimum of 538 MET-min/wk of exercise.