Cognitive disinhibition and infrequent moderate-to-intense physical activity linked with obesity in U.S. soldiers

To explore the relationship between body weight status and neurocognitive functioning in soldiers.

U.S. soldiers (N = 109) answered survey questions and completed neurocognitive tests including simple reaction time, code substitution, procedural reaction time, go-no-go, matching to sample, code substitution recall, and four versions of the Stroop test including congruent (color and meaning of word agreed); incongruent (color and meaning of word differed); neutral (nonsense words appeared), and emotional (combat-related words such as "I.E.D" and "convoy" appeared). Self-reported heights and weights were used to calculate BMI. A BMI ≥ 30.00 kg/m² was categorized as obese. Multivariate analysis of variance was used to analyze weight status differences (p ≤ 0.05) across neurocognitive variables. Binomial logistic regression analysis with obesity as the dependent variable was used to ascertain the contributions (p ≤ 0.05) of exercise and the neurocognitive measures that differed based on weight status.

Twenty-nine participants (26.6%) were obese. The obese group had significantly lower scores on code substitution, and both neutral and emotional Stroop tasks. Only Stroop emotional scores, p = 0.022, OR = 0.97, and frequency of moderate/intense physical activity, p = 0.009, OR = 0.10, were significant predictors of weight status.

Obesity was associated with less frequent moderate/intense physical activity and compromised executive functioning, namely decrements in response inhibition. Given the design and sample size, additional research is needed to better understand the direction of the relationship between these variables and to inform research related to the treatment and prevention of obesity within military populations.

Level III, case-control analytic study.