Longitudinal Impact Of The Covid-19 Pandemic On Cardiorespiratory Fitness Of Youth In The United States

PURPOSE: Previous literature has shown that the COVID-19 pandemic led to a decline in physical activity levels among youth in the United States. This could have a negative impact on youth fitness and subsequent disease risk. The purpose of the study was to examine longitudinal changes in cardiorespiratory fitness (CRF) among schools participating in the NFL PLAY 60 FitnessGram Project. METHODS: The sample consisted of 264 schools (elementary: n = 237, junior/middle: n = 24, high: n = 24, and other: n = 3) from 21 states who reported CRF data once during the pandemic (Fall 2020 - Fall 2021) and at least one additional time before (Fall 2019 - Spring 2020) or after (Spring 2022 - Spring 2023). CRF results, assessed via PACER test, 1-mile run, or 1 mile-walk, were entered into the FitnessGram® software. Estimated maximal oxygen consumption (mL/kg/min) was categorized into one of three groups (Healthy Fitness Zone (HFZ), Needs Improvement, and Health Risk) based on age- and sex-specific criterion-referenced standards. While adjusting for grade level and sex, mixed effects regression models were used to estimate pandemic-related changes in CRF and HFZ achievement odds ratios. In a subset of 116 schools who provided learning modality data to the Center for Disease Control and Prevention, we examined the relationship between in-person and remote/hybrid environments and CRF. RESULTS: There was a significant decrease in CRF in youth during the COVID-19 pandemic. Adjusted aerobic capacity was 0.54 mL/kg/minute lower in girls and 0.85 mL/kg/minute lower in boys during the pandemic (p < 0.001). Compared to the pre- and post-pandemic periods, students were significantly less likely to achieve HFZ during the pandemic (OR: 0.72, 95% CI: 0.66 - 0.78). In a subset of 116 school who reported learning modality by week, those in remote/hybrid environments for 15-22 weeks were significantly more likely to achieve the HFZ compared to those who were hybrid/remote for shorter periods of time (0 - 4 weeks: OR: 1.25, 95% CI: 1.05 - 1.49; 5-14 weeks: OR: 1.33, 95% CI: 1.09 - 1.63). CONCLUSION: This is the first study to examine the longitudinal impact of the COVID-19 pandemic on youth CRF. Compared to pre- and post-pandemic, CRF was significantly lower during the pandemic, but the reduction does not appear to be the result of extended remote/hybrid environments. This work is part of the NFL PLAY 60 FitnessGram Project sponsored by the NFL Foundation.