The present study aimed to examine relationships between executive function (EF) and variables of aerobic fitness. Participants were 32 healthy older adults (M age = 65.1, SD = 6.6 years). We measured the first ventilatory threshold (VeT1) and the kinetics of oxygen uptake (O2), heart rate (HR), and muscle deoxygenation [HHb] during treadmill walking of either constant, moderate intensity, or increasing intensity. We assessed EF with a computerized Stroop test and Stroop measures of correct answers, reaction time, and percent interference. We found the Stroop interference score to be negatively associated with the VeT1 (r = -0.387, p = 0.031) and positively associated with the on-transition aerobic metabolism time constant (τ) of HR (r = 0.519, p = 0.003), O2 (r = 0.454; p = 0.010), and [HHb] (r = 0.644, p = 0.001). Correct responses were negatively related with τHR (r = -0.372, p = 0.039) and τO2 (r = -0.500, p = 0.004). The Stroop average reaction time, congruent reaction time and incongruent reaction time were positively related to τ[HHb] (r = 0.507, p = 0.010; r = 0.437, p = 0.029; r = 0.558, p = 0.004, respectively). Better EF was associated with faster on-transition aerobic metabolism and higher aerobic fitness among older adults.
Keywords: elderly; executive function; mono-exponential; oxygen uptake kinetics; ventilatory threshold.