Secondary Logo

Journal Logo

Institutional members access full text with Ovid®

Load Carriage and Physical Exertion Influence Cognitive Control in Military Scenarios


Medicine & Science in Sports & Exercise: December 2019 - Volume 51 - Issue 12 - p 2540–2546
doi: 10.1249/MSS.0000000000002085

Introduction Physical exertion has both beneficial and detrimental effects on cognitive performance, particularly cognitive control. Research into physical exertion under conditions of load carriage is particularly important given that military personnel and first responders must perform optimally under such combinatorial physical stressors. The present work sought to characterize cognitive control as a function of physical exertion and load carriage in a military operational scenario.

Methods Thirty-one active-duty soldiers underwent a 4-h operationally relevant and fatiguing scenario that included two 1-h foot marches under load carriage conditions of 8.8, 47.2, 50.7 kg on each of three separate days. During each foot march, they completed five 5-min blocks of an auditory go/no-go task of response inhibition.

Results Results showed that response inhibition declined with increasing load carriage and physical exertion, as evidenced by lower proportion of correct responses, higher proportion of false alarms, and lower response sensitivity between all three load conditions, particularly upon successive foot marches and time blocks within each foot march.

Conclusions The results support previous laboratory-based work on load carriage and physical exertion and suggest that deteriorations in cognitive control witnessed in laboratory settings are more pronounced within realistic operational scenarios akin to those encountered by military personnel and first responders.

US Army Combat Capabilities Development Command Soldier Center (CCDC Soldier Center), Natick, MA

Address for correspondence: Grace E. Giles, Ph.D., US Army Combat Capabilities Development Command Soldier Center (CCDC Soldier Center), 10 General Greene Avenue, Natick, MA 01760; E-mail:

Submitted for publication March 2019.

Accepted for publication June 2019.

Online date: July 6, 2019

© 2019 American College of Sports Medicine