RESUMO
Introduction: This systematic review and meta-analysis aimed to investigate adherence and retention rates to home-based video exercise programs and identify key factors associated with these rates in older adults to understand the effectiveness of home-based video exercise interventions. Methods: We searched PubMed, Web of Science, and Scopus for articles addressing adherence to and retention of home-based video exercise programs. The study was conducted following PRISMA recommendations. Results: A total of 26 articles, including 1,292 participants older than 65, were included in the final qualitative and quantitative syntheses. The weighted mean of the retention rate was 91.1, and of the attendance rate was 85.0, with low I2 = 3.5, not significant p = 0.409 heterogeneity. The generalized regression models showed a positive effect of session duration on the attendance rate (%), where the possible change from <20 min to >60 min duration could decrease the attendance rate (%) B = -24.390 (p <0.001). The delivery method had a significant effect, where the absence of live contact with the coach in web-based or DVD-delivered interventions could decrease the attendance rate (%) compared to the online sessions B = -11.482 (p = 0.010). The lockdown during the COVID-19 pandemic had a positive effect on both the attendance rate (%) B = 10.321 (p = 0.019) and retention rate (%) B = 9.577 (p = 0.032). Conclusions: This systematic review and meta-analysis indicate that supervised home-based video exercise programs lasting less than 60 min might be a suitable and sustainable exercise mode to keep older adults active, especially in times resembling feelings of confinement.
RESUMO
Physical exercise may activate a number of important biochemical processes in the human body. The aim of this systematic review and meta-analysis was to identify the long-term effect of physical activity on irisin blood levels. We searched PubMed, Scopus, and Web of Science for articles addressing the long-term effect of physical exercise on irisin blood levels. Fifty-nine articles were included in the final qualitative and quantitative syntheses. A statistically significant within-group effect of exercise on irisin blood levels was in 33 studies; out of them, the irisin level increased 23× and decreased 10×. The significant positive between-groups effect was found 11×. Furthermore, the meta-analysis indicated that physical exercise had a significant positive effect on irisin blood levels (SMD = 0.39 (95% CI 0.27-0.52)). Nevertheless, considerably high heterogeneity was found in all the analyses. This systematic review and meta-analysis indicate that physical exercise might increase irisin blood levels; however, the results of individual studies were considerably inconsistent, which questions the methodological detection of irisin by ELISA kits.