The effects of exercise and body armor on cognitive function in healthy volunteers

Police officers routinely wear body armor to protect themselves against the threat posed by firearms and edged weapons, yet little is known of the cognitive effects of doing so. Two studies investigated the effects of exercise and body armor on working memory function in healthy volunteers. In study 1, male undergraduates were assigned to one of four groups: (i) brief exercise, (ii) brief exercise wearing body armor, (iii) extended exercise, and (iv) extended exercise wearing body armor. In study 2, university gym members were assigned to one of two groups: (i) wearing body armor and (ii) not wearing body armor. In both studies, heart rate and oral temperature were measured before, immediately after, and 5 minutes after exercise. The phonemic verbal fluency task and digits backward test were administered at the same time points. In both studies, a mixed analysis of variance revealed statistically significant changes to the cognitive functioning of participants. A change in cognitive strategy was observed, reflected by a decrease in executive function (switches) and an increase in nonexecutive function (cluster size). These data suggest that the cognitive effects of exercise and body armor may have profound implications for police officers' ability to make tactical decisions.