Physical Education and Sports Science Academic Group, Nanyang Technological University, Singapore.
School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore.
BMJ Mil Health. 2024 Jan 25;170(1):37-42. doi: 10.1136/bmjmilitary-2021-002061.
Combat boots are essential protective gear for military personnel. The purposes of the present study were to examine (1) the influence of combat boot type on ground reaction force (GRF) variables and perceived comfort during unloaded and loaded walking and (2) the relationship between comfort and biomechanical measurements.
Four types of combat boots with different physical features (eg, mass, thickness) and mechanical properties (eg, cushioning, rigidity) were compared across 61 male participants with experience in military marching while carrying heavy loads. In each boot type, participants completed a 10-m walk under an unloaded and a 20-kg loaded conditions at their preferred speeds. Peak force and loading rate during walking were measured using the loadsol wireless in-shoe sensor system. Comfort level was assessed using a 7-point Likert scale. Difference between loaded and unloaded walking, and across boot types were statistically compared. Correlation analyses were performed between comfort and GRF variables.
On average across all boot types, participants walked 2.1% slower when carrying 20-kg loads while experiencing 24.3% higher peak force and 20.8% higher loading rate. Boot D was perceived as most comfortable, followed by boots C, B and A (χ(2)=115.4, p<0.001). Participants walked slightly faster (p=0.022, η = 0.052) and displayed higher loading rates (p<0.001, η =0.194) in the two more comfortable boots (C and D) than the less comfortable boots (A and B). No significant correlations were found between perceived comfort and any GRF variables.
Combat boot features can influence perceived comfort ratings substantially during walking, whereas biomechanical differences among boot types are more subtle regardless of load conditions. The lack of relationship between comfort and force variables suggests that both subjective and objective measurements should be considered for comprehensive evaluation of combat boots.
作战靴是军事人员必备的防护装备。本研究的目的是（1）研究作战靴类型对空载和负载行走时地面反作用力（GRF）变量和感知舒适度的影响；（2）研究舒适度与生物力学测量之间的关系。
本研究比较了 61 名有负重行军经验的男性参与者在穿着 4 种不同物理特性（如质量、厚度）和机械特性（如缓冲、刚性）的作战靴时的行走情况，每种作战靴类型下，参与者都在空载和 20kg 负载条件下以自己喜欢的速度完成 10m 的行走。使用 loadsol 无线鞋内传感器系统测量行走过程中的峰值力和加载率。舒适度水平采用 7 分制 Likert 量表评估。对空载和负载行走以及不同靴型之间的差异进行统计学比较。对舒适度和 GRF 变量进行相关分析。
在所有靴型中，参与者平均负重 20kg 时行走速度减慢 2.1%，峰值力增加 24.3%，加载率增加 20.8%。靴 D 被认为是最舒适的，其次是靴 C、B 和 A（χ(2)=115.4，p<0.001）。在更舒适的靴（C 和 D）中，参与者行走速度稍快（p=0.022，η=0.052），加载率更高（p<0.001，η=0.194），而在不太舒适的靴（A 和 B）中则相反。感知舒适度与任何 GRF 变量之间均无显著相关性。
作战靴的特征在行走过程中会极大地影响感知舒适度评分，而靴型之间的生物力学差异则较为微妙，无论负载条件如何。舒适度和力变量之间缺乏关系表明，在全面评估作战靴时，应同时考虑主观和客观测量。
