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Cited by 68Thermoregulation and physiological responsesCardiovascular and exercise physiologyMuscle metabolism and nutrition

Oral tyrosine supplementation improves exercise capacity in the heat

Tumilty, Les, Davison, Glen, Beckmann, Manfred, Thatcher, Rhys·2011·European Journal of Applied Physiology
DOI 10.1007/s00421-011-1921-4
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Abstract

Increased brain dopamine availability improves prolonged exercise tolerance in the heat. It is unclear whether supplementing the amino-acid precursor of dopamine increases exercise capacity in the heat. Eight healthy male volunteers [mean age 32 ± 11 (SD) years; body mass 75.3 ± 8.1 kg; peak oxygen uptake ([Formula: see text]) 3.5 ± 0.3 L min(-1)] performed two exercise trials separated by at least 7 days in a randomised, crossover design. Subjects consumed 500 mL of a flavoured sugar-free drink (PLA), or the same drink with 150 mg kg body mass(-1) tyrosine (TYR) in a double-blind manner 1 h before cycling to exhaustion at a constant exercise intensity equivalent to 68 ± 5% [Formula: see text] in 30°C and 60% relative humidity. Pre-exercise plasma tyrosine:large neutral amino acids increased 2.9-fold in TYR (P < 0.01), while there was no change in PLA (P > 0.05). Subjects cycled longer in TYR compared to PLA (80.3 ± 19.7 min vs. 69.2 ± 14.0 min; P < 0.01). Core temperature, mean weighted skin temperature, heart rate, ratings of perceived exertion and thermal sensation were similar in TYR and PLA during exercise and at exhaustion (P > 0.05) despite longer exercise time in TYR. The results show that acute tyrosine supplementation is associated with increased endurance capacity in the heat in moderately trained subjects. The results also suggest for the first time that the availability of tyrosine, a nutritional dopamine precursor, can influence the ability to subjectively tolerate prolonged submaximal constant-load exercise in the heat.

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  • Among six studies of endurance exercise performance in physically trained young men, five found no significant difference between tyrosine and placebo, while one found tyrosine enhanced performance.

    “While one study found tyrosine to enhance endurance exercise performance (Tumilty et al., 2011), five studies found no significant differences between tyrosine and the placebo (Strüder et al., 1998;Sutton et al., 2005;Chinevere et al., 2002;Tumilty et al., 2014;Watson et al., 2012).”

    From Behavioral and cognitive effects of tyrosine intake in healthy human adults (2015) · cites this paper as Tumilty et al., 2011

  • Tyrosine reduced response inhibition reaction times in one study.

    “Tyrosine reduced response inhibition reaction times in one study (Tumilty et al., 2011).”

    From Behavioral and cognitive effects of tyrosine intake in healthy human adults (2015) · cites this paper as Tumilty et al., 2011

  • The mixed results on endurance exercise performance suggest that tyrosine loading may not be very useful for that purpose.

    “The mixed results on endurance exercise performance suggest that tyrosine loading may not be very useful in this context: only one out of six similarly designed studies found tyrosine to enhance performance relative to placebo (Tumilty et al., 2011).”

    From Behavioral and cognitive effects of tyrosine intake in healthy human adults (2015) · cites this paper as Tumilty et al., 2011

  • Tyrosine supplements (150 mg/kg) reduce many of the adverse effects of various types of acute stress.

    “A series of studies have indicated that tyrosine supplements (150 mg/kg) reduce many of the adverse effects of various types of acute stress [126].”

    From Exercise-induced stress behavior, gut-microbiota-brain axis and diet: a systematic review for athletes (2016) · cites this paper as [126]

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Authors
Tumilty, L., Davison, G., Beckmann, M., & Thatcher, R.
Affiliations
Aberystwyth University (GB)
Corresponding author
Tumilty, Les
ORCID
Venue
European Journal of Applied Physiology
Publisher
Springer Science and Business Media LLC
Published
2011-03-25
Volume
111
Issue
12
Pages
2941-2950
ISSN
  • 0020-9376 (ISSN-L)
  • 1439-6319
  • 1439-6327
DOI
10.1007/s00421-011-1921-4
OpenAlex
W2046303374
Cited by
68
References
52
Citations by year
2026: 4 · 2025: 5 · 2024: 7 · 2023: 2 · 2022: 4 · 2021: 1 · 2020: 2 · 2019: 3 · 2018: 4 · 2017: 5 · 2016: 3 · 2015: 11 · 2014: 11 · 2013: 3 · 2012: 2
FWCI
3.71
Type
journal article
Language
en
Open access
closed
Licence
www.springer.com/tdm (tdm)
Locations
  • European Journal of Applied Physiology (publishedVersion)
  • PubMed (publishedVersion)
  • Kent Academic Repository (University of Kent) (submittedVersion)
Funders
Aberystwyth University
Topics
  • Health Sciences › Medicine › Physiology › Thermoregulation and physiological responses
  • Health Sciences › Medicine › Complementary and alternative medicine › Cardiovascular and exercise physiology
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Muscle metabolism and nutrition
Keywords
tyrosine supplementation, exercise in the heat, heat acclimation, exercise endurance, dopamine precursor, plasma tyrosine, large neutral amino acids, thermal sensation, heat stress, cycling to exhaustion
MeSH terms
Adult, Body Temperature, Double-Blind Method, Heart Rate, Hot Temperature, Humans, Male, Physical Endurance, Skin Temperature, Thermosensing, Tyrosine, Exercise, Exercise Tolerance, Cross-Over Studies, Dietary Supplements

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