School of Human and Health Sciences, University of Huddersfield, Huddersfield, UK.
Human Movement Biomechanics Research Group, KU Leuven, Leuven, Belgium.
Ergonomics. 2021 Sep;64(9):1191-1204. doi: 10.1080/00140139.2021.1909754. Epub 2021 May 3.
The determinants of energy saving phenomena reported for load carried on the head, back and in a doublepack remain unclear. This study compared the energetic, kinematic and kinetic responses to head (H), back (B) and doublepack (DP) loading. Fifteen volunteers walked on an instrumented treadmill at 3 kmh with 0, 3, 12 and 20 kg in each loading method. Whole body motion, ground reaction forces (GRF) and metabolic cost were measured. H was less economical than B ( = 0.014) and DP ( = 0.010). H was also associated with increased step length ( = 0.045), decreased cadence ( = 0.001), greater trunk ( < 0.001) and hip ( < 0.001) extension and greater minimum vertical GRF ( = 0.001) than B and DP. In conclusion, no energy saving was found for head- or back-loading but economy may be improved with methods that cause smaller perturbations from unloaded walking. Energy saving phenomena have been reported for load carried on the head, back and in a doublepack, yet the determinants are unclear. This study shows that smaller perturbations from unloaded to loaded walking are associated with improved economy for certain load carriage conditions, such as the doublepack.
头部、背部和双肩背包负重的能量节省现象的决定因素尚不清楚。本研究比较了头部（H）、背部（B）和双肩背包（DP）负重的能量、运动学和动力学响应。15 名志愿者以 3km/h 的速度在带仪器的跑步机上行走，每种负重方式下分别负重 0、3、12 和 20kg。测量全身运动、地面反作用力（GRF）和代谢成本。H 比 B（ = 0.014）和 DP（ = 0.010）更不经济。H 还与步长增加（ = 0.045）、步频降低（ = 0.001）、躯干（ < 0.001）和髋关节（ < 0.001）伸展更大以及最小垂直 GRF 更大（ = 0.001）有关，而 B 和 DP 则更小。总之，头部或背部负重没有发现节能现象，但对于引起与空载行走较小扰动的方法，经济性可能会提高。头部、背部和双肩背包负重的能量节省现象已有报道，但决定因素尚不清楚。本研究表明，与空载到负载行走的较小扰动相关的某些负载携带条件，例如双肩背包，与经济性提高有关。
