Effects of Weight Carried by Soldiers: Combined Analysis of Four Studies on Maximal Performance, Physiology, and Biomechanics

Abstract

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Kinematic analysis of males with transtibial amputation carrying military loads

“…The two speed conditions were completed in separate sessions on two consecutive days; the three loading conditions were randomized within each session. These speeds and load magnitudes are consistent with published military guidance regarding the speed and load magnitudes to be carried during a foot march [5,15] and are representative of values used in previous studies assessing load carriage by nondisabled servicemembers [16][17].…”

“…More than 1,400 servicemembers have sustained injuries resulting in a major limb amputation during recent conflicts [1], and among those with a transtibial amputation (TTA), approximately 20 percent remain on Active Duty [2]. Yet despite investigations of the physiological and biomechanical responses to load carriage in nondisabled military and civilian populations [3][4][5][6], there remains limited objective evidence [7] regarding the ability of servicemembers with lower-limb amputations to meet military standards when executing physical tasks (e.g., load carriage).…”

Load carriage, human performance, and employment standards

“…The consequences of load carriage on graded maximal exercise performance have been evaluated by many groups over the last 30-40 years (Raven et al 1977;Louhevaara et al 1985Louhevaara et al , 1995White and Hodous 1987;Polcyn et al 2002;Eves et al 2005;Dreger et al 2006;Northington et al 2007;Taylor et al 2012;Peoples et al 2016;Phillips et al 2016a). From this research, the universal observation was a reduced work tolerance time, but without necessarily modifying the peak physiological responses.…”

The effect of load distribution within military load carriage systems on the kinetics of human gait

“…Forward lean is the body's way of balancing out the moments caused by adding additional load to the posterior of the body. The greater 8 the load or the further away this load is placed from the body's neutral CoM, the greater the forward lean (Attwells et al, 2006;Harman et al, 2000;Polcyn et al 2002).…”

“…The effect that military load carriage has on ground reaction force (GRF) parameters has been examined previously in the literature (Birrell et al, 2007;Harman et al, 2000;Kinoshita, 1985;Lloyd and Cooke, 2000a;Polcyn et al, 2002;Tilbury-Davis and Hooper, 1999). However, less attention has been paid to the distribution of load on the body, particularly with respects to the biomechanical changes of gait.…”