JMIR Publications

ABSTRACT

Background:

Physical activity ameliorates chronic stress. Latest research suggests a relation between resilience and physical fitness. Beneficial adaptations of the hypothalamic-pituitary-adrenal axis, the sympathetic nervous system, the endocannabinoid system, and the tryptophan pathway, induced by an active lifestyle, are considered to be resilience conducive. However, detailed knowledge on the molecular link between the effects of acute and chronic physical exercise and an improved resilience is missing.

Objective:

Therefore, we implement a human exercise intervention trial addressing the main hypotheses: (1) web-based exercise training improves aerobic capacity of physically inactive adults, which (2) is accompanied by improved resilience. In this setting, we will analyze the relation of resilience parameters with innate and acquired aerobic capacity as well as circulating signaling molecules.

Methods:

70 healthy physically inactive (<150min/week physical activity) adults (18-45y) will be randomly assigned to an intervention or control group. Participants in the intervention group receive weekly training utilizing progressive endurance and interval running individually adapted to their training performance via web-based physician support. A standardized incremental treadmill exercise test is performed before and after the intervention period of eight weeks to determine innate and acquired aerobic capacity. Before and after the intervention psychological tests and questionnaires that characterize parameters implicated in resilience (including impulse control, working memory, stress coping, emotion regulation) will be applied. Blood, and saliva will be sampled for analysis of lactate, cortisol, endocannabinoids, catecholamines, kynurenic acid, cell-free DNA and further circulating signal transducers. Statistical analysis will provide comprehensive knowledge on the relation of aerobic capacity and resilience, and furthermore, the capacity of peripheral factors to mediate the promoting effects of exercise on resilience.

Results:

The study was registered in October 2019. Enrollment began in September 2019. Out of 161 subjects, who were initially screened via telefon survey, 43 fulfilled the inclusion criteria and were included. Among the 17 participants in the intervention group, and 14 participants in the control group, who completed the study (total 31), no serious adverse event has been reported. Four participants withdrew during the programm (individual reasons), and 8 participants have not yet completed or begun the program due to the Covid-19 pandemic. Enrollment and data analysis are ongoing, and results are expected to be submitted for publication in October 2021.

Conclusions:

Our study aims to demonstrate that an increase in physical activity with a simultaneous improvement in aerobic capacity is associated with an increase in resilience. This study design allows to investigate the effect of an active lifestyle on circulating molecular marker levels and their relationship to resilience factors. This will offer novel approaches for the diagnosis of depression and the therapy by exercise prescription. Clinical Trial: DRKS00018078, registered October 02, 2019, German Clinical Trials Register. Retrospectively registered: First participant September 10, 2019.