Association Between Physical Activity, Heart Rate Variability and Major Depressive Disorders: An Umbrella Review

Physical activity (PA) has positive effects on physical and mental health. Nevertheless, two thirds of individuals with major depressive disorders (MDD) do not meet PA recommendations. Furthermore, MDD is associated with increased cardiovascular risk and autonomic nervous system dysfunction. This depression-related dysfunction is expressed by low heart rate variability (HRV). In contrast, regular PA has been shown to improve autonomic regulation over time as indicated by higher HRV values. The overarching aim of this umbrella review is to examine the complex interrelationship and mutual influence between MDD, PA, and HRV. We aim to answer the following questions: (I) How does PA affect depressive symptoms? (II) How are HRV and MDD related? (III) How does PA affect HRV? Medline, Embase, PsycINFO, SPORTDiscus, and Epistemonikos were searched for systematic reviews and meta-analyses from their inception until 5 July 2024. Reviews were included if they presented the effects of PA interventions on depression severity in individuals with MDD for part I, if they showed the differences in HRV parameters between healthy individuals and individuals with MDD for part II, and if they presented the effects of PA interventions on HRV parameters in healthy individuals for part III. The quality of the included reviews was assessed by Assessing the Methodological Quality of Systematic Reviews (AMSTAR 2) criteria. This umbrella review included 90 reviews. Part I shows that various types of PA are effective in reducing symptoms of depression in individuals with MDD. In addition, there is a similar reduction with PA compared with pharmacological treatment. Part II demonstrates that time-based and frequency-based HRV values are lower in individuals with MDD than in healthy individuals. Part III shows that different types of PA can improve time-based, frequency-based and nonlinear HRV parameters in healthy individuals. This comprehensive umbrella review demonstrates the importance of PA to reduce symptoms of depression and to have a positive impact on autonomic function. Further studies suggest that PA can also improve HRV in individuals with MDD. In the future, randomized controlled trials should be conducted to examine which types and forms of PA are effective in positively affecting HRV in individuals with MDD according to standardized parameters in the area of HRV and depression severity. The protocol for this umbrella review was a priori registered with PROSPERO: CRD42021278665.