Consistent with the literature, this research found that the 1,500 m freestyle at maximal speed led to a decrease in cognitive function; IC in the Stroop task, SGT, and TMT were reduced, and serum 5-HT increased, which is possibly due to central fatigue and cognitive decline, affecting the effective contraction of skeletal muscle (Kieran et al., 2018; Zhai et al., 2018). This evidence concerns the gene HTR5A and Mental deterioration.