Hemodynamic and Executive Function Responses to A Single Bout of Aerobic and Deep-leg Squat Exercise

An acute bout of aerobic exercise ‘boosts’ postexercise executive function (EF) and is a finding - in part - attributed to an exercise-induced increase in cerebral blood flow (CBF). It is, however, less well known whether body weight exercise (i.e., deep leg squats) elicit a similar EF benefit. Indeed, deep leg squats induce intermittent changes to CBF and may result in biomolecule alterations that provide a larger magnitude postexercise EF benefit. PURPOSE: The present study sought to determine whether distinct CBF reactivity to deep leg squats and continuous aerobic exercise differentially benefit the magnitude of a postexercise EF benefit. METHODS: Participants (age range: 18 to 25 years) completed three 15-min conditions involving: (1) a non-exercise control, (2) deep leg squats with eight 1-min intervals (20 squats/min) separated by 1-min of rest, and (3) 15-min of moderate intensity aerobic exercise (60% HRR via cycle ergometer at 70 rpm). During all conditions, transcranial Doppler ultrasound (TCD) measured middle cerebral artery velocity (MCAv) to provide an estimate of exercise-based changes in CBF. EF was examined prior to and following each condition via antisaccades (i.e., saccade mirror-symmetrical to target). RESULTS: As expected, baseline to steady-state MCAv did not reliably vary for the control condition (p = 0.16), whereas deep leg squats and aerobic exercise produced peak increases in systolic MCAv of 26 cm/s and 40 cm/s, respectively (ps < 0.001). For the EF task, control condition antisaccade reaction times (RTs) did not vary from pre- to postexercise (p = 0.34), whereas deep leg squats and aerobic exercise produced a postexercise reduction in RTs (ps < 0.04). Moreover, a two-one sided statistic indicated that the magnitude of the RT reduction in deep leg squat and aerobic conditions was equivalent (p < 0.05). In other words, the magnitude of the EF benefit was equivalent across the two conditions. CONCLUSION: Deep leg squats increase CBF and provide a postexercise benefit to EF equivalent to aerobic exercise. Thus, for a single bout of exercise a hysteretic (deep leg squats) and continuous (aerobic) increase in CBF does not impact the magnitude of an EF benefit. Supported by: Natural Sciences and Engineering Research Council (NSERC) of Canada