Division of Sport and Exercise Sciences, University of Abertay Dundee, UK.
Ergonomics. 2011 Apr;54(4):380-91. doi: 10.1080/00140139.2011.558636.
The purpose of this study was to compare the kinetic responses associated with ground reaction force measurements to both head-loading and back-loading in a group of Xhosa women. Altogether, 16 women were divided into two groups based on their experience of head-loading. They walked over a force plate in three conditions: unloaded or carrying 20 kg in either a backpack or on their head. The most striking finding was that there was no difference in kinetic response to head-loading as a consequence of previous experience. Considering the differences between the load carriage methods, most changes were consistent with increasing load. Head-loading was, however, associated with a shorter contact time, smaller thrust maximum and greater vertical force minimum than back-loading. Both loading conditions differed from unloaded walking for a number of temporal variables associated with the ground contact phase, e.g. vertical impact peak was delayed whilst vertical thrust maximum occurred earlier. STATEMENT OF RELEVANCE: Consideration of the kinetics of head and back load carriage in African women is important from a health and safety perspective, providing an understanding of the mechanical adaptations associated with both forms of load carriage for a group of people for whom such load carriage is a daily necessity.
本研究的目的是比较与头部加载和背部加载相关的地面反作用力测量的动力学反应，该研究对象为一组科萨妇女。共有 16 名妇女根据其头部加载经验分为两组。她们在三种条件下在力板上行走：空载或头部或背包中携带 20 公斤。最引人注目的发现是，由于以前的经验，头部加载的动力学反应没有差异。考虑到负载携带方式的差异，大多数变化与负载增加一致。与背部加载相比，头部加载与较短的接触时间、较小的推力最大值和更大的垂直力最小值相关。这两种加载条件与空载行走相比，地面接触阶段的许多时间变量都有所不同，例如，垂直冲击峰值延迟，而垂直推力最大值出现更早。研究的相关性：从健康和安全的角度来看，考虑非洲妇女的头部和背部负重的动力学非常重要，这有助于理解与这两种形式的负重相关的机械适应性，对于一组日常需要负重的人来说，这是必要的。
