Acute Effects of Mindfulness-based Intervention on Athlete Cognitive Function: An FNIRS Investigation

Background: Mindfulness-based intervention (MBI) as a psychological treatment is adopted in the sports field, but its effect during competition has not been explored. This study investigated the acute effect of a brief MBI on athletes' cognitive function after a 45-min, lab-based soccer protocol.

Methods: In a single-blind randomized counter-balanced crossover design, 17 male soccer players completed two main trials-an MBI trial and a control trial. The MBI trial was provided with a brief MBI after 45-min exercise; the control trial was instead assigned a travel-related audio to listen to at that time. In each main trial, cognitive function (i.e., Stroop task for inhibition; Corsi-block tapping task for working memory), salivary cortisol, blood lactate and mental fatigue were measured at baseline (pretest) and after the intervention (posttest). The cerebral oxygenation status was recorded using functional near-infrared spectroscopy during the cognitive function test.

Results: The brief MBI improved working memory performance in terms of both reaction time (pre vs. post, P = 0.02, d = 0.71) and accuracy (pre vs. post, P = 0.009, d = 0.58), supported by eliciting increased oxyhemoglobin concentration in the prefrontal cortex of the brain. Whereas a slightly better cognitive performance for MBI trial than control trial at posttest (P = 0.37, d = 0.32) accompanied by a lower oxyhemoglobin concentration. A lower mental fatigue level (P = 0.05, d = 0.6) and lower cortisol concentration (P = 0.04, d = 0.65) were observed in the MBI trial than in the control trial after the intervention at posttest. The decreased cortisol concentration correlated with increased inhibition performance in the MBI trial.

Conclusion: The acute effect of MBI on athletes' mental fatigue and cortisol concentration was detected, and the beneficial effect on working memory was preliminarily supported. In general, MBI is recommended to be adopted at half-time of a soccer game.