title: Effects of aerobic exercise under different thermal conditions on human somatosensory processing.
abstract: The present study aimed to investigate the effects of aerobic exercise on human somatosensory processing recorded by somatosensory evoked potentials (SEPs) under temperate [TEMP, 20°C and 40% relative humidity (RH)] and hot (HOT, 35°C and 30% RH) environments. Fifteen healthy subjects performed 4 × 15-min bouts of a moderate cycling exercise [mean power output: 156.5 ± 7.7 (SE) W], with a 10-min rest period and received a posterior tibial nerve stimulation at the left ankle before and after each exercise bout; SEPs were recorded in five sessions; 1st (pre), 2nd (post-1st exercise bout), 3rd (post-2nd exercise bout), 4th (post-3rd exercise bout), and 5th (post-4th exercise bout). The peak latencies and amplitudes of the P37, N50, P60, and N70 components at Cz were evaluated. The latencies of P37, N50, P60, and N70 were significantly shorter with the repetition of aerobic exercise, and these shortened latencies were significantly greater in the HOT condition than in the TEMP condition (P37: 3rd, P < 0.05, and 5th, P < 0.01; P60: 4th, P < 0.05, and 5th, P < 0.01; N70: 4th, P < 0.05, and 5th, P < 0.001). No significant differences were observed in the amplitudes of any SEP component under either thermal condition. These results suggest that the conduction velocity of the ascending somatosensory input was accelerated by increases in body temperature, and aerobic exercise did not alter the strength of neural activity in cortical somatosensory processing.
authors.affiliation: Department of Health Sciences, Faculty of Human Life and Environment, Nara Women's University, Nara, Japan; and.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Nakata
authors.affiliation: Graduate School of Humanities and Sciences, Nara Women's University, Nara, Japan.
authors.forename: Misaki
authors.initials: M
authors.lastname: Oshiro
authors.affiliation: Graduate School of Humanities and Sciences, Nara Women's University, Nara, Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Namba
authors.affiliation: Department of Health Sciences, Faculty of Human Life and Environment, Nara Women's University, Nara, Japan; and shiba@cc.nara-wu.ac.jp.
authors.forename: Manabu
authors.initials: M
authors.lastname: Shibasaki
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D001831:Body Temperature / Q000502:physiology*; D017753:Ecosystem; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008297:Male; D009431:Neural Conduction / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D013696:Temperature; D055815:Young Adult
keywords: central fatigue; dynamic exercise; hyperthermia; somatosensory evoked potentials; tactile