Effects of high-intensity interval training on depressive symptoms: A systematic review and meta-analysis.

UNLABELLED: The objective of this systematic review and meta-analysis is to investigate the effect of high-intensity interval training (HIIT) on depressive symptoms, including an examination of its impact across different populations, intervention durations, and control groups through subgroup analysis.

METHODS: A systematic literature search was conducted using the following databases: Cochrane, Embase, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang Data Knowledge Service Platform. The search covered the period from January 1, 2000, to December 31, 2022.

RESULTS: The meta-analysis included 34 randomized controlled trials, involving a total of N = 1607 participants. HIIT had a small but significant effect on depressive symptoms compared to the control group [SMD = -0.40, 95%CI (-0.60, -0.20), I2  = 73%]. However, subgroup analyses revealed no moderating effect of health status or exercise duration on depressive symptoms. HIIT did not have a statistically significant effect on depressive symptoms when compared with other types of exercise [SMD = -0.15, 95% CI (-0.30, 0.01), I2  = 10%]. HIIT demonstrated a medium effect size in reducing depressive symptoms compared to a non-active control group [SMD = -0.53, 95% CI (-0.84, -0.21), I2  = 80%].

CONCLUSIONS: HIIT confers benefits in mitigating depressive symptoms. Compared to non-active control group, HIIT yields moderate improvements in depressive symptoms. We look forward to exploring more moderating effects in the future, such as HIIT modalities, frequency, and so on. In summation, these findings substantiate the use of HIIT as a means to alleviate symptoms of depression.