Effect of tyrosine ingestion on cognitive and physical performance utilising an intermittent soccer performance test (iSPT) in a warm environment

Chrismas, Bryna C. R.; Aldous, Jeffrey W. F.; Coull, Nicole A.; Watkins, Samuel L.; Aldous, Jeffrey W F; Warren, Lee K.; Dascombe, Benjamin; Chrismas, Bryna C R; Mauger, Alexis R.; Abt, Grant; Taylor, Lee

Abstract

Purpose: The aim of this study was to investigate the effect of tyrosine ingestion on cognitive and physical performance during soccer-specific exercise in a warm environment. Methods: Eight male soccer players completed an individualised 90-minute soccer-simulation (iSPT), on a non-motorised treadmill, on two occasions, within an environmental chamber (25°C, 40% RH). Participants ingested tyrosine (TYR; 250 mL sugar free drink plus 150 mg.kg body mass⁻¹ TYR) at both 5h and 1h pre-exercise or a placebo control (PLA; 250 mL sugar free drink only) in a double-blind, randomised, crossover design. Cognitive performance (vigilance and dual-task) and perceived readiness to invest physical effort (RTIPE) and mental effort (RTIME) were assessed: pre-exercise, half-time, end of half-time and immediately post-exercise. Physical performance was assessed using the total distance covered in both halves of iSPT. Results: Positive vigilance responses (HIT) were significantly higher (12.6 ± 1.7 v 11.5 ± 2.4, p = 0.015) with negative responses (MISS) significantly lower (2.4 ± 1.8 v 3.5 ± 2.4, p = 0.013) in TYR compared to PLA. RTIME scores were significantly higher in the TYR trial when compared to PLA (6.7 ± 1.2 v 5.9 ± 1.2, p = 0.039). TYR had no significant (p > 0.05) influence on any other cognitive or physical performance measure. Conclusion: The results show that TYR ingestion is associated with improved vigilance and RTIME when exposed to individualised soccerspecific exercise (iSPT) in a warm environment. This suggests that increasing the availability of TYR may improve cognitive function during exposure to exercise-heat stress.

Citation

Coull, N. A., Watkins, S. L., Aldous, J. W. F., Warren, L. K., Chrismas, B. C. R., Mauger, A. R., …Taylor, L. (2015). Effect of tyrosine ingestion on cognitive and physical performance utilising an intermittent soccer performance test (iSPT) in a warm environment. European journal of applied physiology, 115(2), 373-386. https://doi.org/10.1007/s00421-014-3022-7

• Acceptance Date: Oct 7, 2014
• Online Publication Date: Oct 19, 2014
• Publication Date: 2015-02
• Deposit Date: Oct 9, 2015
• Publicly Available Date: Nov 23, 2017
• Journal: European journal of applied physiology
• Print ISSN: 1439-6319
• Electronic ISSN: 1439-6327
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 115
• Issue: 2
• Pages: 373-386
• DOI: https://doi.org/10.1007/s00421-014-3022-7
• Keywords: Central fatigue; Tyrosine; Cognitive function; Intermittent exercise; Heat
• Public URL: https://hull-repository.worktribe.com/output/379540
• Publisher URL: http://link.springer.com/article/10.1007/s00421-014-3022-7
• Copyright Statement: ©2015 University of Hull
• Additional Information: Author's accepted manuscript of article published in: European journal of applied physiology, 2015, v.115, issue 2. The final publication is available at Springer via http://dx.doi.org/10.1007/s00421-014-3022-7