Changes in Body Weight, Physical Activity, and Lifestyle During the Semi-lockdown Period After the Outbreak of COVID-19 in China: An Online Survey.

Background: The outbreak of novel coronavirus (COVID-19) provided an opportunity to undertake an online survey to study the relationships between body weight changes with changes in physical activity and lifestyle during an unusual event of forced isolation or quarantine.Methods: We distributed an electronic questionnaire using the popular social application WeChat to adults from any province of China except Hubei Province, the epicenter of the outbreak. The questionnaire asked for demographic information, body weight, physical activity and lifestyle factors before, during the quarantine.Results: Of 376 questionnaires returned, 339 were valid (90.2%). During the period of semi-lockdown, both females and males with BMI < 24 gained weight, while males with BMI ≥ 24 lost weight while females with BMI≥24 gained weight. The average steps per day and the average moderate or vigorous-intensity exercise declined significantly for both males and females during the semi-lockdown. Changes in body weight inversely correlated with changes in steps per day and moderate or vigorous-intensity exercise during the quarantine.Conclusions: Normal weight individuals, who are not normally troubled by overweight or obesity had less awareness of weight gain than people with a BMI≥24. Under the conditions of the semi-lockdown, they tended to gain weight.