The effects of high intensity interval training on quality of life: a systematic review and meta-analysis
Megan E. Griffiths, Jamie Edwards, Jack McNamara, Andy Galbraith, Stewart Bruce‐Low, J. M. O’Driscoll
Abstract
Abstract Aim This study aimed to ascertain the impact of high intensity interval training (HIIT) on physical, mental, and overall quality of life (QoL) through a comprehensive systematic review and meta-analysis. Subject and methods A systematic search for relevant trials was performed via PubMed, the Cochrane Library and Web of science as well as the manual screening of prior meta-analyses and their respective reference lists (PROSPERO reference: CRD42022326576). Adult controlled trials investigating the effects of a >2-week HIIT intervention with an eligible non-intervention control group were considered. As the primary outcome, studies were required to include at least one measure of physical and/or mental and/or overall QoL, on any validated QoL domain, pre and post intervention. Results Twenty-two studies with twenty-four effect sizes were included; seventeen comparing HIIT and overall QoL, fourteen comparing HIIT and physical QoL and thirteen studies comparing HIIT and mental QoL. There was a statistically significant improvement in physical (SMD= 0.405, 95% CI: 0.110- 0.700, p= 0.007), mental (SMD= 0.473, 95% CI: 0.043 –0.902, p=0.031) and overall QoL (SMD= 0.554, 95% CI 0.210-0.898, p=0.002) following a program of HIIT. Secondary analysis of 5 studies comparing HIIT against moderate intensity continuous training demonstrated no significant difference in improvement between the two modes (SMD= -0.094, CI= -0.506-0.318, p=0.655). Conclusion Engaging in HIIT produces statistically significant improvements in physical, mental, and overall quality of life in clinical and non-clinical populations at a small to moderate effect size. Furthermore, HIIT appears as effective as MICT in improving overall QoL, offering a more time-efficient exercise option.