Raustorp Anders, Boldemann Cecilia, Mårtensson Fredrika, Sternudd Catarina, Johansson Maria
School of Sport Sciences, Linnaeus University, Kalmar, Sweden.
Int J Adolesc Med Health. 2013;25(2):171-6. doi: 10.1515/ijamh-2013-0026.
Active travel has a potential to increase children's physical activity (PA). Pedometers offer a valid option to measure PA, but do not capture cycling activity. Children's self-reported cycling distances can be analyzed by the Geografic Information System (GIS).
To combine pedometry and GIS mapping to identify the relative amount of cycling in children's PA.
Of all children in 4th grade (n=187) in Staffanstorp Sweden, 144 had valid pedometer data. Fifty-six children were non-cyclists while 88 children (32 boys, 47 girls, 9 gender unknown) reported at least one cycle journey.
Cycle trips were entered into GIS and calculated to total cycling distance. Average length of the single distances cycled per day was 676 m (SD=534 m). A previously reported cycling speed (13.5 km/h) was used to calculate time spent cycling. Consequently distance=676 m, speed=13.5 km/h=13,500 m/3600 s=3.75 m/s and time=676m/3.75m/s=180.26 s=3 min. Expenditure of 4 and 5 metabolic equivalents (METs) has in children been reported equivalent to 122 and 127 steps/min, respectively. We estimated 4.7 METs (13.5 km/h) as 126 steps for every min of cycling (127-122=5×0.7=125.5).
The daily mean cycle distance was 676 m, on average 379 additional steps/day for cycling children (min. 21, max. 1385, SD=299) with no gender difference. Additional "steps" obtained by cycling corresponded to on average 3% of their PA.
The relative contribution of cycling in 10-year-old children's PA level is quite small and stable between children across different levels of activity levels, regardless of gender.
主动出行有可能增加儿童的身体活动（PA）。计步器是测量身体活动的有效工具，但无法记录骑行活动。儿童自我报告的骑行距离可通过地理信息系统（GIS）进行分析。
结合计步测量和GIS地图绘制，以确定儿童身体活动中骑行的相对占比。
在瑞典斯塔凡斯托普的所有四年级儿童（n = 187）中选取，其中144名儿童有有效的计步器数据。56名儿童不骑车，88名儿童（32名男孩、47名女孩、9名性别不明）报告至少有一次骑行。
将骑行行程录入GIS并计算出总骑行距离。每天单次骑行的平均长度为676米（标准差 = 534米）。使用先前报告的骑行速度（13.5公里/小时）来计算骑行时间。因此，距离 = 676米，速度 = 13.5公里/小时 = 135,000米/3600秒 = 3.75米/秒，时间 = 676米/3.75米/秒 = 180.26秒 = 3分钟。据报告，儿童4和5代谢当量（METs）的消耗分别相当于每分钟122步和127步。我们估计以4.7代谢当量（13.5公里/小时）骑行每分钟相当于126步（127 - 122 = 5×0.7 = 125.5）。
每日平均骑行距离为676米；骑车儿童平均每天额外增加379步（最少21步，最多1385步，标准差 = 299），无性别差异。骑行所获得的额外“步数*”平均占其身体活动量的3%。
骑行在10岁儿童身体活动水平中的相对贡献相当小，且在不同活动水平的儿童中较为稳定，与性别无关。
*注：原文中“steps”在不同语境下含义不同，这里为了使译文通顺，“Additional "steps" obtained by cycling”翻译为“骑行所获得的额外‘步数’”，实际指的是与骑行相关的身体活动量换算成的相当于计步器步数的数值 。
