The effects of high intensity interval training on quality of life: a systematic review and meta-analysis

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. 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, p= 0.007), mental (SMD= 0.473, p=0.031) and overall QoL (SMD= 0.554, 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, p=0.655). 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.