Comparative Effects of Acute HIIE and MICE on Executive Function, Prefrontal Oxyhaemoglobin Responses, and Related Biomarkers in Sedentary Young Adults: A Randomized Crossover Trial

Background/Objectives: To compare the acute effects of high-intensity interval exercise (HIIE) and moderate-intensity continuous exercise (MICE) on executive-function performance, prefrontal oxyhaemoglobin (Oxy-Hb) signals, brain-derived neurotrophic factor (BDNF), and lactate in sedentary young adults.

Methods

Fifteen participants (10 men, 5 women; 22 ± 2 years; BMI 23.07 ± 4.12 kg/m2) completed HIIE, MICE, and seated control sessions in randomized order with 7-day washouts. Stroop, N-back, and Switching tasks; prefrontal fNIRS; plasma BDNF; and blood lactate were assessed before and after each condition. Correlation and indirect-effect analyses were exploratory.