The Effect of Exercise on Prevention of the Common Cold: A Meta-Analysis of Randomized Controlled Trial Studies

Abstract

BackgroundBecause there is no specific treatment for the common cold, many previous studies have focused on prevention of the common cold. There were some studies reporting that regular, moderate-intensity exercise increases immunity and prevents the common cold. We conducted a meta-analysis to determine the effects of exercise on prevention of the common cold.MethodsWe searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL for studies released through June 2013. We manually searched the references. Two authors independently extracted the data. To assess the risk of bias of included literature, Cochrane Collaboration's tool for assessing risk of bias was used. Review Manager ver. 5.2 (RevMan, Cochrane Collaboration) was used for statistical analysis.ResultsFour randomized controlled trials were identified. A total of 281 participants, 134 in the exercise group and 147 in the control group, were included. The effect of exercise on the prevention of the common cold had a relative risk (RR) of 0.73 (95% confidence interval [CI], 0.56 to 0.95; I2 = 7%). The mean difference of mean illness days between exercise group and control group was -3.50 (95% CI, -6.06 to -0.94; I2 = 93%). In the subgroup analysis, the RR of under 16 weeks exercise was 0.79 (95% CI, 0.58 to 1.08).ConclusionIn this meta-analysis, regular, moderate-intensity exercise may have an effect on the prevention of the common cold. But numbers of included studies and participants were too small and quality of included studies was relatively poor. Subsequent well-designed studies with larger sample size are needed to clarify the association.

Hygiene Behaviors Associated with Influenza-Like Illness among Adults in Beijing, China: A Large, Population-Based Survey

“…In this study, regular physical exercise was also found to be a protective factor against the incidence of ILI. A recent meta-analysis of four studies obtained similar results that regular, moderate-intensity exercise may have an effect on the prevention of the common cold, and the risk of the common cold in exercise group was 27% lower as compared to the control group [ 10 ]. The protective effects of regular physical exercise on these infectious diseases may be partially explained by enhanced activity of several immune parameters that could be important in limiting or clearing viral infection [ 11 ].…”

Does Exercise Prevent the Common Cold?

“…Second, Lee et al 1) ignored our large cohort study which found that physical activity at work, and at leisure, had no association with the common cold risk when adjusted for potential confounders. 4) We analyzed the relationship between leisure time physical activity and common cold incidence in 3,470 males who were followed up for 2 years.…”

“…Lee et al 1) carried out a meta-analysis of the potential role of exercise in preventing the common cold, and calculated that exercise might reduce the incidence of colds by 27% (relative risk [RR], 0.73; 95% confidence interval [CI], 0.56 to 0.95). However, their study has important limitations.…”

“… 4) We analyzed the relationship between leisure time physical activity and common cold incidence in 3,470 males who were followed up for 2 years. In contrast, the meta-analysis by Lee et al 1) included only 281 participants. Therefore, our study had much narrower CIs.…”

“…Given that adults usually have 2 to 4 colds per year, 5) an average person should exercise for 1 to 2 years to prevent 1 episode of the common cold on the basis of the RR = 0.73 estimate. Lee et al 1) indicated that regular exercise means having exercise sessions 5 times per week. Assuming that 1 exercise session takes 1 hour, 5 exercise sessions per week for 1 year sums up to 250 hours in total; corresponding to 10 full days.…”