A new study published in the International Journal of Environmental Research and Public Health found that roughly 45 minutes of vigorous exercise during the pandemic sufficiently reduced negative emotions in a sample of Chinese college students.
Strict social distancing measures implemented during the pandemic have impacted the daily lives of citizens around the world. Despite the mental health impact of such prolonged social isolation, little research has considered possible mitigating factors that might reduce mental suffering.
In a longitudinal study, Yao Zhang and colleagues aimed to explore the mental health of college students quarantined during the peak of the coronavirus and to consider the possible mitigating effects of exercise.
The study involved 66 Chinese college students who stayed at home during the outbreak to comply with social distancing regulations. The students completed three online surveys at roughly two-week intervals, on the following dates: February 19, 2020, March 5, 2020, and March 20, 2020. During this time, the pandemic continued to increase in severity and steadily peaked in China. None of the subjects were diagnosed with COVID-19 during the study.
Students were asked to indicate how many days in the past two weeks they had engaged in light physical activity, moderate physical activity, and vigorous physical activity and how many minutes they had typically spent on each type of exercise. Subjects also reported their sleep quality, and, using the Depression and Anxiety Stress Scale (DASS), their negative emotions in the past week. Aggressiveness was additionally assessed with a questionnaire measuring hostility, anger, verbal aggression, and physical aggression.
Results showed that almost 85% of the sample reported worries about COVID-19 and 42% showed sleep scores that indicated poor quality of sleep. As the number of local COVID-19 deaths increased, participants’ sleep quality dropped, with sleep efficiency showing the strongest relationship with the number of COVID-19 deaths. Interestingly, while neither negative emotion nor global DASS score was related to the number of COVID-19 deaths, aggressiveness was negatively correlated with death count. The authors suggest that this drop in aggressiveness reflects the fact that people have begun to “realize the fragility of life” and are “cherishing every moment.”
When it came to physical activity, researchers used something called MET values to compute each subject’s energy expenditure, depending on the intensity of the activities they reported. On average, participants exerted 355 METs of vigorous physical activity per week.
Physical activity was related to lower DASS scores, lower negative emotions, and reduced depression. Interestingly, further analysis pointed to a sweet spot when physical activity produced its protective benefits. The authors describe a “dose-response curve” between physical activity and negative emotions, demonstrating that both too much and too little physical exercise worsened negative emotions. “A suitable amount to minimize negative emotions occurred when weekly physical activity was about 2500 METs, corresponding to 108 min of light, 80 min of moderate, or 45 min of vigorous physical activity every day,” the authors report.
This recommended amount of exercise is higher than previous studies which have suggested 60 minutes of moderate-vigorous physical activity per day. The authors suggest that during this difficult time, people need more physical activity than usual “to offset the psychological burden and negative emotions” brought about by the pandemic.
The study, “Mental Health Problems during the COVID-19 Pandemics and the Mitigation Effects of Exercise: A Longitudinal Study of College Students in China”, was authored by Yao Zhang, Haoyu Zhang, Xindong Ma, and Qian Di.
(Image by Taco Fleur from Pixabay)