Acute effect of three different exercise training modalities on executive function in overweight inactive men: A secondary analysis of the BrainFit study

There is currently a consensus about the positive effects of physical exercise on cognition. However, the exercise intensity-dependent effect on executive function remains unclear. Thus, the aim of this study was to compare the acute effects of high-intensity aerobic interval training (HIIT), progressive resistance training (PRT), or combined training (PRT + HIIT) on executive function indicators in overweight inactive adult men (aged 18-30 years old). The participants were screened and excluded for medical conditions known to impact cognitive functioning, which was measured with the Montreal Cognitive Assessment (MoCA) screening cognitive test. A randomised, parallel-group clinical trial was conducted among 36 adults who were randomly assigned to a HIIT (n = 12), PRT (n = 7), PRT + HIIT (n = 7), or control group (n = 10) until the energy expenditure of 400-500 kcal. Cognitive inhibition and attention capacity were examined using the Stroop test and d2 test of attention, respectively, and were obtained pre-exercise for baseline measurement and 1 min post-exercise for each exercise training modality. Cognitive inhibition measured by the Stroop test was improved after the HIIT protocol for the domains of reading by +5.89 (η2 = 0.33), colour naming +9.0 (η2 = 0.60), interference +10.1 (η2 = 0.39), and index interference +6.0 (η2 = 0.20). Additionally, the PRT + HIIT group had an increase for the reading condition of +7.1 (η2 = 0.40), colour naming +7.5 (η2 = 0.80), and interference +5.8 (η2 = 0.39). In regard to attentional capacity, the HIIT group elicited small to medium improvements in the concentration level domain of +21.7 (η2 = 0.44), total performance domain +56.6 (η2 = 0.50), and consistency domain -3.0 (η2 = 0.27). These results were similar in the PRT and PRT + HIIT groups in the concentration level and items-processed domains (P < 0.05). In conclusion, acute HIIT and PRT + HIIT sessions reported important effect sizes than PRT alone for cognitive inhibition and attention capacity. Taken together, the results suggest that even short-term exercise interventions can enhance overweight adults' executive functions.