Time trial performance in normal and high ambient temperature: is there a role for 5-HT?

Authors: Roelands, Bart¹; Goekint, Maaike¹; Buyse, Luk¹; Pauwels, Frank¹; Schutter, Guy¹; Piacentini, Francesca¹; Hasegawa, Hiroshi²; Watson, Phil³; Meeusen, Romain⁴

Source: European Journal of Applied Physiology, Volume 107, Number 1, September 2009 , pp. 119-126(8)

Publisher: Springer

Buy & download fulltext article:

Price: $47.00 plus tax (Refund Policy)

Abstract:

The original central fatigue hypothesis suggested that fatigue during prolonged exercise might be due to higher 5-HT activity. Therefore, we examined the effects of acute administration of a selective 5-HT reuptake inhibitor (SSRI) on performance and thermoregulation. Eleven healthy trained male cyclists completed four experimental trials (two in 18°C, two in 30°C) in a double-blind randomised crossover design. Subjects ingested either a placebo (PLA: lactose 2 × 10 mg) or citalopram (CITAL 2 × 10 mg) on the evening before and the morning of the trial. Subjects cycled for 60 min at 55% W _max, immediately followed by a time trial (TT) to measure performance. The significance level was set at P < 0.05. Acute SSRI did not significantly change performance on the TT (18°C P = 0.518; 30°C P = 0.112). During recovery at 30°C, core temperature was significantly lower in the CITAL trial (P < 0.012). At 30°C heart rate was significantly lower after exercise in CITAL (P = 0.013). CITAL significantly increased cortisol concentrations at rest (P = 0.016), after the TT (P = 0.006) and after 15-min recovery (P = 0.041) at 30°C. 5-HT reuptake inhibition did not cause significant reductions in performance. Core temperature was significantly lower only after the time trial in heat after CITAL administration. The present work failed to prove whether or not 5-HT has an exclusive role in the onset of centrally mediated fatigue during prolonged exercise in both normal and high ambient temperature.

Keywords: Central fatigue; Serotonin; Exercise; Heat; Citalopram

Document Type: Research article

DOI: http://dx.doi.org/10.1007/s00421-009-1109-3

Affiliations: 1: Department Human Physiology and Sports Medicine, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium 2: Laboratory of Exercise Physiology, Faculty of Integrated Arts and Sciences, Hiroshima University, Higashihiroshima, Japan 3: School of Sport and Exercise Sciences, Loughborough University, Leicestershire, LE11 3TU, UK 4: Department Human Physiology and Sports Medicine, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium, Email: rmeeusen@vub.ac.be

Publication date: 2009-09-01

Time trial performance in normal and high ambient temperature: is there a role for 5-HT?

Buy & download fulltext article:

Tools

Key

Text size:

Useful pages