A 3-dimensional biomechanical analysis of British Army foot-drill in untrained personnel: Implications for lower-extremity injury risk

Rawcliffe, Alex; Morrison, Andrew; Graham, Scott; Simpson, Richard; Psycharakis, Stelios; Connaboy, Chris

Abstract

Abstract presented at 4th International Congress on Soldiers’ Physical Performance, 28 November - 1 December 2017
Melbourne Australia
Purpose: To investigate and compare kinematic, kinetic, ground reaction force (GRF) and temporal parameters of British Army footdrill performed by civilian men and women.
Methods: A two-way ANOVA model (foot drill [5 levels]; sex [2 levels]) with repeated measures on the within-subject factor (foot drill) was used to determine the differences in the GRF components and temporal variables, while a three-way ANOVA model (foot drill [5 levels]; joint [3 levels]; sex [2 levels]) with repeated measures on the two within-subject factors (foot drill, joint) was used to determine differences in the joint data. Footdrills
analysed consisted of quick march, stand at attention, stand at ease, halt, and walking at preferred speed. Healthy men (n = 8, 26.1 ± 0.8 yrs, 179.6 ± 2.5 cm, 79.3 ± 6.3 kg) and women (n = 8, 24.2 ± 2.3 yrs, 175.8 ± 4.8 cm, 62.4 ± 4.7 kg) volunteered. A 3-dimensional lower-extremity analysis of four foot-drills was conducted using time-synchronised motion analysis and force plates. A three-segment six-degrees of freedom link model was used to quantify 3D coordinate data.
Results: Men and women produced knee extension angles ≤42◦ across foot-drill whilst producing peak vertical GRF (PvGRF) and vertical rate of force development values in excess of 6 bodyweights (BW) and 700 BW per second (BW/s), respectively. Women exhibited greater knee and hip extension, greater knee abduction
(valgus), and greater ankle inversion angles at initial contact and PvGRF across foot-drill, whilst producing significantly lower impact forces than men. Men produced greater knee extensor moments than women across foot drills.
Conclusions: The greater extended lower-extremity posture and knee valgus motion in women, and the greater impact loading forces and knee extensor moments of men are suggested to hold implications for the potential risk of musculoskeletal injury in men and women.

• Journal Article Type: Other
• Acceptance Date: Jan 2, 2017
• Online Publication Date: Nov 15, 2017
• Publication Date: 2017-11
• Deposit Date: Jan 11, 2018
• Journal: Journal of Science and Medicine in Sport
• Print ISSN: 1440-2440
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 20
• Pages: S152
• DOI: https://doi.org/10.1016/j.jsams.2017.09.528
• Keywords: Physical Therapy, Sports Therapy and Rehabilitation; Orthopedics and Sports Medicine
• Public URL: http://researchrepository.napier.ac.uk/Output/1011877