Association between physical activity and sedentary behavior with the risk of overweight and obesity in primary school students

Abstract

Objective To investigate the association between moderate to vigorous physical activity (MVPA) and sedentary behavior with the risk of overweight/obesity in children, and to provide a reference for health life style of primary school students.

Methods From November to December 2018, a cross-sectional survey of 949 school children aged 9-12 years in Guangdong Province was conducted. Children were classified as normal weight or overweight/obesity based on body mass index (BMI). Participants were advised to wear a wristwatch-type Gene Active accelerometer for 24 hours to record MVPA and sedentary time. Children’s screen time (ST) was provided by parents. Poisson regression was used to analyze the independent associations between MVPA, sedentary time, screen time and overweight/obesity risk.

Results About 20.8% (197) of the children were overweight/obesity. The percentage of children who met the MVPA recommendation was 22.1% (210), and the amount of sedentary time (excluding sleep) during the school day was 60.8% (577), or as high as 8.5 hours per day. Only 12.3% (117) of children have less than two hours of screen time per day. Compared with Q4, pupils with MVPA of Q1 had a 4.38 higher risk of overweight/obesity compared with normal pupils ( P<0.01), no similar associations were observed for sedentary time. Compared with pupils who met the recommended MVPA, pupils with lower MVPA had an increased risk of overweight/obesity by 2.54 times (95% CI = 1.59-3.77). Pupils with more than 2 hours per day had an increased risk of overweight/obesity by 1.87 times (95% CI = 1.21-3.02) compared with pupils with less than 2 hours per day.

Conclusion The risk of overweight/obesity decreases with the increase of MVPA. The proportion of students meeting the MVPA recommendation is relatively low, the proportion exceeding screen time recommendation is high.

Abstract

【摘要】 目的 探讨中度到大强度体力活动 (moderate to vigorous physical activity, MVPA) 和久坐行为与小学生超重/肥胖 风险之间的关联, 为改善小学生不良生活方式提供参考。 方法 2018 年 11一12 月对广东省某市 949 名 9~12 岁小学生进 行横断面调査。根据体质量指数 (BMI) 将小学生划分为正常和超重/肥胖两组。实验对象 24 h 戴腕表式 Gene active 加速 度计, 对 MVPA 和久坐时间进行区分和记录。由父母记录并提供小学生的屏幕时间。采用 Possion 回归分析 MVPA、久坐 时间、屏幕时间与超重/肥胖风险之间独立关联。 结果 20.8% (197 名) 的小学生超重/肥胖。小学生符合 MVPA 推荐值 比例为 22.1% (210 名), 上学日久坐时间 (不包括睡眠时间) 为 60.8% (577 名), 髙达 8.5 h/d。仅有 12.3% (117 名) 的小学 生屏幕时间 ≤2 h/d。与 Q4 相比, MVPA 为 Q1 的小学生与正常组小学生相比, 其超重/肥胖的风险比体质量正常的小学生 髙出 4.38 倍 ( P<0.01), 且与久坐时间无关。与符合 MVPA 推荐值的小学生相比, 未达到 MVPA 推荐值的小学生的超重/肥胖风险增加了 2.54倍 (95% CI =1.59~3.77)。每天 >2 h 的小学生超重/肥胖的风险比每天 ≤2 h 的小学生增加了 1.87 倍 (95% CI = 1.21~3.02)。 结论 MVPA 时间越长, 超重/肥胖的风险越低。能达到 MVPA 时间要求的小学生比例偏低, 小学 生的屏幕时间大多超出推荐值。