Moderate-to-vigorous Physical Activity Improves Inhibitory Control In Adults With Overweight And Obesity

Interrupting sitting with brief bouts of light physical activity (PA) may improve executive functions (EFs) in older adults with overweight and obesity (OW/OB). However, the effects of moderate-to-vigorous intensity PA (MVPA) breaks to sitting on EFs in younger and middle-aged adults with OW/OB remain unknown. PURPOSE: To examine the effects of interrupting 3-h continuous sitting every 30 min with 3.5-min MVPA breaks relative to a sedentary attention control condition (standardized social interactions; SED) on EFs in young and middle-aged aduts with OW/OB. METHODS: Data from 19 adults (12 [63%] females; Mage = 29.9 ± 7.5 years; MBMI = 30.0 ± 3.6 kg/m2; MVO2peak = 32.1 ± 6.5 mL/kg/min) were analysed from the SITLess randomized crossover trial (NCT04926207). Inhibitory control was expressed as accuracy and reaction time (RT) on incongruent trials of a modified Eriksen flanker task. Working memory (WM) was expressed as a d prime (d’) index on the 2-back task (z-scoretarget accuracy - z-scorefalse alarms). Information processing was measured with RTs on congruent flanker trials and accuracy and RT on a 1-back task. Generalized Linear Mixed Effects Models with Time (pre, post) by Condition (MVPA, SED) interactions and simple effects measured within each time point were used to test intervention effects. RESULTS: Participants achieved on average 71 ± 13.3 % of their maximum heart rate (HRmax) during MVPA and 39.6 ± 5.1% HRmax during SED conditions. The Time x Condition interactions were significant for congruent (F(1,53) = 4.08, P = 0.48; b = -16.6 ± 8.2, 95% CI: -33.2, -0.12) and incongruent (F(1,37) = 5.05, P = 0.03; b = -20.4 ± 9.1, 95% CI: -38.7, -2.01) trials. MVPA breaks resulted in faster responses on congruent (b = -17.3 ± 5.5 ms, P = 0.01; 95% CI: 5.7, 29.0) and incongruent (b = -16.7 ± 7.1 ms, P = 0.03; 95% CI: 1.6, 31.7) flanker trials compared to SED with no differences on RTs during pre-test (Ps ≥ 0.39). No other behavioral effects were observed (Ps ≥ 0.06). CONCLUSION: Interrupting prolonged sitting with brief MVPA breaks improves inhibitory control and information processing in young and middle-aged adults with OW/OB. Short MVPA breaks could be used as a time-efficient strategy to enhance EFs during long sitting hours. Keywords: prolonged sitting, physical activity breaks, executive functions, obesity, crossover trial Campus Research Board #RB20025