Background:

Lockdowns implemented by governments all over the world during the current COVID-19 pandemic highly affect most people’s daily activities. Albeit lowering infection rates, their potential impact on cardiovascular prevention behaviour has not been assessed yet. Therefore, we aimed to investigate the pandemic-related alteration of physical activity and nutrition among young adults.

Methods:

In this cross-sectional study, we enrolled 1,964 voluntary participants among Bavarian universities between March and April 2020. Study subjects were asked to complete a standardized online questionnaire, semi-quantitatively evaluating the amount and type of physical activity and food intake before and during the pandemic lockdown. Additionally, quantitative activity tracking by smartphones or wearables was performed in a subgroup of participants. The Cardiovascular Prevention During COVID-19 Pandemic Lockdown in Young Adults (COLA) trial was registered at clinicaltrials.gov (NCT04361877).

Results:

In the study cohort (mean age 23.3 ±4.0 years, 71.5 % female, mean body mass index 22.1 ±4.5 kg/m²), overall physical activity decreased in 44.5% of participants (n=867) after implementation of lockdown, in 32.8% (n=639) daily physical activity increased (Figure A). Among low active participants (<2 hours per week) 77% reported increased physical activity levels. Social distancing resulted in a drastic change in the type of physical activity and was mainly limited to running, cycling, and strength training after the lockdown. Activity tracking in 662 subjects revealed a reduction of daily step count after implementation of lockdown (6,777 [IQR 4,967-8,825], versus 4,829 [IQR 2,338-7,841] steps per day, p<0.001, Figure B). 

The overall food amount increased in 31.2% of participants (n=610) during lockdown and decreased in 16.8% (n=328). A multinominal regression model revealed that an increased food intake was less likely in male participants (OR, 0.7 [CI 0.6-0.9]) and more likely with increasing BMI (OR, 1.4 [CI, 1.3-2.0]), increased sports activity (OR, 1.3 [CI, 1.2-1,8]), and augmented mental stress (OR 1.4 [1.1-1.7]). Increase in food intake was mainly triggered by higher amounts of bread (increased in 46.8%, n=284) and confectionary consumption (increased in 64.4%, n=389).

Conclusion:

The COVID-19 pandemic lockdown significantly affected physical activity levels and eating habits in young adults. Impaired cardiovascular prevention behaviour warrants further investigation to evaluate long-term effects on weight changes and comorbidities.