Hong Y, Li J X, Wong A S, Robinson P D
Department of Sports Science & Physical Education, The Chinese University of Hong Kong, Shatin, New Territories.
Ergonomics. 2000 Jun;43(6):717-27. doi: 10.1080/001401300404698.
Fifteen male primary school children, aged 10 years, were selected to carry school bags of 10, 15 and 20% of their own body weights, where 0% body weight was used as a control. Maximum oxygen uptake (VO2max) tests were conducted on a motorized treadmill using a continuous incremental protocol. During the load carrying test, subjects walked on a treadmill at 1.1 m s(-1) for 20 min at each load condition. Blood pressures were measured before, immediately following, and at 3 and 5 min after every trial. Heart rate and expired VO2 were recorded before, during and 5 min after walking using a cardiopulmonary function system. The results showed a significant difference in oxygen uptake, energy expenditure and the recovery of blood pressure rise for between 10 and 20% body weight load conditions. The carrying weight of a school bag for children could be recommended as 10% of body weight because it was not significantly different from 0% load in the metabolic cost.
选取了15名10岁的男性小学生，让他们分别背负相当于自己体重10%、15%和20%的书包，其中0%体重作为对照。使用连续递增方案在电动跑步机上进行最大摄氧量（VO2max）测试。在负重测试期间，受试者在每个负荷条件下以1.1米/秒的速度在跑步机上行走20分钟。每次试验前、试验后立即以及试验后3分钟和5分钟测量血压。使用心肺功能系统在行走前、行走期间和行走后5分钟记录心率和呼出的VO2。结果表明，在体重负荷为10%至20%的条件下，摄氧量、能量消耗和血压上升恢复情况存在显著差异。儿童书包的负重可建议为体重的10%，因为其代谢成本与0%负荷无显著差异。
