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

journal contribution
posted on 02.09.2015, 09:02 authored by Nicole Coull, Samuel L. Watkins, Jeffrey W.F.A. Aldous, Lee K. Warren, Bryna C.R. Chrismas, Benjamin Dascombe, Alexis R. Mauger, Grant Abt, Lee Taylor
Purpose The aim of this study was to investigate the effect of tyrosine (TYR) ingestion on cognitive and physical performance during soccer-specific exercise in a warm environment. Methods Eight male soccer players completed an individualised 90 min soccer-simulation intermittent soccer performance test (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 5 h and 1 h 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 vs 11.5 ± 2.4, p = 0.015) with negative responses (MISS) significantly lower (2.4 ± 1.8 vs 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 vs 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 soccer-specific exercise (iSPT) in a warm environment. This suggests that increasing the availability of TYR may improve cognitive function during exposure to exercise-heat stress.

History

School

  • Design

Published in

European Journal of Applied Physiology

Volume

115

Issue

2

Pages

373 - 386

Citation

COULL, N. et al., 2014. 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), pp. 373 - 386.

Publisher

© Springer-Verlag

Version

VoR (Version of Record)

Publisher statement

This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/

Publication date

2014

Notes

Closed access.

ISSN

1439-6327

Language

en