[Comparison of status of physical activity time at school and influencing factors in students in China, 2010 and 2014].

Objective: To compare the probability of physical activity (PA) time ≥1 hour at school and influencing factors in students in China between 2010 and 2014. Methods: We used the data of 2010 and 2014 Chinese National Survey on Students' Constitution and Health (CNSSCH). The surveys covered the Han students aged 9-22 years and Tibetan students aged 9-18 years (Tibet). The participants were primary school students (9-12 years old), junior high school students (13-15 years old), senior high school students (16-18 years old) and college students (19-22 years old). The probability of PA time ≥1 hour at school was compared using χ(2) tests between 2010 and 2014 survey years. Log-binomial Regression was used to estimate the relative risk (RR) for the probability of PA time ≥1 hour at school in different age groups. Results: The overall probability of PA time ≥1 hour at school in students aged 9-22 years was 20.5% in 2010, and 23.8% in 2014. The difference between 2010 and 2014 was significant (P<0.001). On the whole, the probability of PA time ≥1 hour at school increased in the eastern, central and western areas in 2014 compared with 2010 (P<0.05), and the increase range was highest in eastern area, followed by western area and central area (P<0.05). The probability of PA time of 1 hour at school in all age groups increased in 2014 compared with 2010 (P<0.05). The increase in the probability of PA time ≥1 hour at school was larger in primary school students than that in high school students and college students (P<0.05). The probability of PA time ≥1 hour at school increased in all age groups in three areas, except in junior and senior high school students in the central area where the probability of PA time ≥1 hour at school decreased. The probability of PA time ≥1 hour at school in primary and junior/senior high school students in the eastern area had the greatest increase, but in college students it had the smallest increase in the three areas. From 2010 to 2014, the changes in the probability of PA time ≥1 hour at school in students in different provinces were quite different, especially in primary school students. The probability of PA time ≥1 hour at school in four age groups increased in only three provinces. With the probability of PA time ≥1 hour at school in primary school students as the reference, the RR in junior high students had no significant change between 2010 and 2014. The RR in senior high school increased from 0.34 (0.33-0.35) in 2010 to 0.36 (0.36-0.37) in 2014, and the RR in college students increased from 0.33 (0.32-0.34) in 2010 to 0.43 (0.42-0.44) in 2014. Conclusions: The probability of PA time ≥1 hour at school in all age groups increased in 2014 compared with 2010, but there were great differences among provinces. The findings of our study suggests that although the national policy played a certain role, the provinces should take specific measures to improve the probability of PA time ≥1 hour at school in students according to their own conditions. In addition, more attention should be paid to PA of older students.目的： 比较中国9~22岁学生2010年与2014年校内体育锻炼1 h的概率及影响因素。 方法： 利用2010年与2014年全国学生体质与健康调研数据，选取年龄为9~22岁的汉族学生和9~18岁的藏族学生（西藏自治区）为研究对象，将研究对象分为小学生（9~12岁）、初中生（13~15岁）、高中生（16~18岁）和大学生（19~22岁）。采用χ(2)检验比较不同年度校内体育锻炼1 h的概率之间的差异，采用log-binomial回归计算不同年龄组间校内体育锻炼1 h的概率的RR值。 结果： 2010年中国9~22岁学生校内体育锻炼1 h的概率为20.5%，2014年为23.8%。相较于2010年，2014年中国9~22岁学生校内体育锻炼1 h的概率整体有所上升（P<0.001），且上升幅度东部>西部>中部地区（P<0.05）。各年龄组校内体育锻炼1 h的概率均有所上升（P<0.05），且小学生校内体育锻炼1 h的概率上升幅度高于初、高中生和大学生（P<0.05）。除中部地区的初、高中生校内体育锻炼1 h的概率不升反降外，其余各年龄组东中西部地区学生校内体育锻炼1 h的概率均上升；东部地区的中小学生校内体育锻炼1 h的概率上升幅度最大，但大学生校内体育锻炼1 h的概率的上升幅度在3个地区中最小。各省学生校内体育锻炼1 h的概率的变化情况差异较大，小学生表现尤为明显。仅有3个省份4个年龄组校内体育锻炼1 h的概率均显著上升。以9~12岁年龄组学生的体育锻炼1 h的概率为参照，13~15岁的RR值从2010年到2014年几乎无变化。16~18岁的RR值从2010年的0.34（95%CI：0.33~0.35）增加到2014年的0.36（95%CI：0.36~0.37，P<0.001），19~22岁的RR值从2010年的0.33（95%CI：0.32~0.34）增加到2014年的0.43（95%CI：0.42~0.44，P<0.001）。 结论： 相较于2010年，2014年各年龄组学生校内体育锻炼1 h的概率均上升，但省间差异较大，这说明国家政策虽然起到了一定的作用，但各省应针对各自的情况采取有针对性的措施来提高学生体育锻炼1 h的概率。此外，高年龄组学生的体育锻炼也应当给予更多的重视。.