JMIR Publications

ABSTRACT

Background:

Societal measures to contain the outspread of COVID-19 (e.g., lockdown, contact restrictions) have been associated with decreased health and well-being. A multitude of pre-pandemic studies identified the beneficial effects of physical exercise on both physical and mental health.

Objective:

Here, we report on the feasibility of a remote physical exercise intervention and its stress-buffering potential in two untrained cohorts: a pre-COVID-19 cohort that completed the intervention in 2019 and a lockdown cohort that started the intervention shortly before pandemic related restrictions were implemented.

Methods:

In a randomized controlled trial, participants were assigned to either an intervention group (IG, n_pre-COVID-19 = 7; n_lockdown = 9) or a control group (CG, n_pre-COVID-19 = 6; n_lockdown = 6). IG participants received weekly individualized training recommendations delivered via web-based support. The intervention period was initially planned for 8 weeks, which was adhered to in the pre-COVID-19 cohort (mean = 8.3 weeks, SD = 0.5) but was extended to on average 17.7 (SD = 2.0) weeks in the lockdown cohort. Participants’ health parameters were assessed pre- and post-intervention: Aerobic capacity was measured as peak oxygen uptake (VO2peak) via cardiopulmonary exercise testing. Depressive symptoms were scored via the depression subscale of the Brief Symptom Inventory-18.

Results:

Dropout rates were low in both cohorts in the IG (pre-COVID-19: 0%, lockdown: 16.7%) and the CG (pre-COVID-19: 0%, lockdown: 20%). The mean adherence to the training sessions of the IG for both cohorts was 84% (SDpre-COVID-19 = 5.5%, SDlockdown cohort = 11.6%). Multivariate analyses of variance in the lockdown cohort indicated deterioration of VO2peak and depressive symptoms from pre- to post-intervention in the CG but no longitudinal changes in the IG. Analyses in the pre-COVID-19 cohort revealed significant increases in VO2peak for the IG compared to the CG but no group effects on depressive symptoms.

Conclusions:

With low dropout rates and a high adherence, the remote intervention was feasible in healthy adults under regular conditions and in the face of pandemic-related stressors. Moreover, our results hint at a stress-buffering effect, as well as a buffering of a lockdown induced deconditioning of remote physical exercise interventions in the pandemic scenario, which can be used in future studies to overcome equally stressful periods of life. Clinical Trial: German Clinical Trials Register (DRKS; DRKS00018078; October 2, 2019)