Citation

Jaworski RL, Jensen A, Niederberger B, Congalton R, Kelly KR. Mil. Med. 2015; 180(3 Suppl): 179-186.

Affiliation

Department of Warfighter Performance, Naval Health Research Center, 140 Sylvester Road-Building 328-208C, San Diego, CA 92106.

Copyright

(Copyright © 2015, Association of Military Surgeons of the United States)

DOI

10.7205/MILMED-D-14-00432

PMID

25747650

Abstract

UNLABELLED: U.S. Marines perform mission tasks under heavy loads which may compromise performance of combat tasks. However, data supporting this performance decrement are limited.

PURPOSE: The aim of this study was to determine the effects of load on performance of combat-related tasks.

METHODS: Subjects (N = 18) ran a modified Maneuver Under Fire ([MANUF], 300 yards [yd] total: two 25-yd sprints, 25-yd crawl, 75-yd casualty drag, 150-yd ammunition can carry, and grenade toss) portion of the U.S. Marine Corps Combat Fitness Test under 4 trial conditions: neat (no load), 15%, 30%, and 45% of body weight, with a shooting task pre- and post-trial.

RESULTS: There was a significant increase in total time to completion as a function of load (p < 0.0001) with a relationship between load and time (r = 0.592, p < 0.0001). Pre- to post-MANUF shot accuracy (p = 0.005) and precision (p < 0.0001) was reduced.

CONCLUSION: Short aerobic performance is significantly impacted by increasing loads. Marksmanship is compromised as a function of fatigue and load. These data suggest that loads of 45% body weight increase time to cover distance and reduce the ability to precisely hit a target.

Language: en