Impact Of The Covid-19 Pandemic Lockdown On Body Mass Index And Physical Fitness Among Chinese University Students

Abstract

PURPOSE: To examine the impact of the COVID-19 pandemic lockdown on body mass index (BMI) and physical fitness (PF) among university students in China. METHODS: A total of 5,164 participants (male: 3,604, 69.8%) aged 18.4 ± 0.6 years from three Chinese universities were included in this study. These students were required to undergo BMI and PF tests by their universities annually. Two cohorts of students (the 1st cohort from Oct. 2018 to Oct. 2019, n = 2614; the 2nd cohort from Oct. 2019 to Oct. 2020, n = 2550) were compared, and 1-year changes in BMI and PFs of the 1st cohort (with no pandemic lockdown exposure: NoPL) and the 2nd cohort (with COVID-19 pandemic lockdown exposure: CoPL) were examined in this study. The changes in BMI and PFs were calculated by subtracting the data at baseline from the data at follow-up. Increase in BMI (the upper 25% of the distribution of the BMI change) and decrease in PFs (the lower 25% of the distribution of PFs changes) were the outcome variables. Odds ratios and 95% confidence intervals (95% CIs) for changes in BMI and PFs including vital capacity, 50-meter sprint, sit and reach, standing long jump, pull-ups (only for males) / timed sit-ups (only for females), and 1,000-meter run (only for males) / 800-meter run (only for females) were calculated using logistic regression models after adjustment for age and all other pre-measurement items. RESULTS: Comparing with the NoPL, the odds ratios (95% CIs) for increase in BMI, and decrease in PFs including vital capacity, 50-meter sprint, sit and reach, standing long jump, pull-ups, and 1,000-meter run were 1.68 (1.44-1.97), 1.03 (0.87-1.22), 3.99 (3.34-4.77), 0.74 (0.63-0.87), 1.13 (0.97-1.32), 2.94 (2.48-3.46), and 1.52 (1.30-1.77), respectively for males in the CoPL. Corresponding results in females for increase in BMI and decrease in PFs were 0.30 (0.23-0.39), 1.06 (0.82-1.36), 2.51 (1.97-3.21), 0.38 (0.29-0.49), 0.99 (0.78-1.26), 1.43 (1.13-1.81), and 2.06 (1.63-2.60). CONCLUSIONS: This study showed that there was a significant impact of the COVID-19 pandemic lockdown on BMI, explosive power, flexibility, muscular strength, aerobic fitness in both males and females. These findings may contribute to the development of targeted intervention strategies for weight loss and PF promotion during the lockdown caused by the public health emergency.