Does an aerobic exercise induced alteration in blood lactate concentration effect brain excitability?

Abstract

Aerobic exercise (AE) is thought to increase corticospinal excitability (CSE), creating an optimal environment for motor learning to occur. During AE, metabolic by-products, including lactate, accumulate in the blood. Increased concentration of lactate during fatiguing exercise has been shown to increase CSE. Our research questions if increased blood lactate concentration mediated by an acute bout of moderate-intensity AE alters CSE. Participants completed two sessions; session 1 consisted of determining peak power output (PPO), and in the second session measures of brain excitability and blood lactate concentration were obtained before, immediately after, and 10-min after a 20-min bout of moderate-intensity AE performed at 60% of PPO. Our results show that no relationship between blood lactate concentration and CSE exists following a bout of moderate intensity AE suggesting that altered lactate concentration is not a factor involved in increasing CSE with AE.