Stable fitness during COVID-19: Results of serial testing in a cohort of youth with heart disease

Abstract

Background: Little is known about how sport and school restrictions early during the novel coronavirus 2019 (COVID-19) pandemic impacted exercise performance and body composition in youth with heart disease (HD).

Methods: A retrospective chart review was performed on all patients with HD who had serial exercise testing and body composition via bioimpedance analysis performed within 12 months before and during the COVID-19 pandemic. Formal activity restriction was noted as present or absent. Analysis was performed with a paired t-test.

Results: There were 33 patients (mean age 15.3 ± 3.4 years; 46% male) with serial testing completed (18 electrophysiologic diagnosis, 15 congenital HD). There was an increase in skeletal muscle mass (SMM) (24.1 ± 9.2-25.9 ± 9.1 kg, p < 0.0001), weight (58.7 ± 21.5-63.9 ± 22 kg, p < 0.0001), and body fat percentage (22.7 ± 9.4-24.7 ± 10.4%, p = 0.04). The results were similar when stratified by age <18 years old (n = 27) or by sex (male 16, female 17), consistent with typical pubertal changes in this predominantly adolescent population. Absolute peak VO₂ increased, but this was due to somatic growth and aging as evidenced by no change in % of predicted peak VO₂. There remained no difference in predicted peak VO₂ when excluding patients with pre-existing activity restrictions (n = 12). Review of similar serial testing in 65 patients in the 3 years before the pandemic demonstrated equivalent findings.

Conclusions: The COVID-19 pandemic and related lifestyle changes do not appear to have had substantial negative impacts on aerobic fitness or body composition in children and young adults with HD.

Keywords: COVID-19; body composition; cardiopulmonary exercise test (CPET); congenital heart disaese; exercise changes.