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Cited by 69Muscle metabolism and nutritionExercise and Physiological ResponsesSports Performance and Training

Contrasting plasma free amino acid patterns in elite athletes: association with fatigue and infection.

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Kingsbury, K J, Kay, L, Hjelm, M·1998·British Journal of Sports Medicine
DOI 10.1136/bjsm.32.1.25PMC PMC1756055
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Abstract

AIM: There is little information on the plasma free amino acid patterns of elite athletes against which fatigue and nutrition can be considered. Therefore the aim was to include analysis of this pattern in the medical screening of elite athletes during both especially intense and light training periods. METHODS: Plasma amino acid analysis was undertaken in three situations. (1) A medical screening service was offered to elite athletes during an intense training period before the 1992 Olympics. Screening included a blood haematological/biochemical profile and a microbial screen in athletes who presented with infection. The athletes were divided into three groups who differed in training fatigue and were considered separately. Group A (21 track and field athletes) had no lasting fatigue; group B (12 judo competitors) reported heavy fatigue at night but recovered overnight to continue training; group C (18 track and field athletes, one rower) had chronic fatigue and had been unable to train normally for at least several weeks. (2) Athletes from each group were further screened during a post-Olympic light training period. (3) Athletes who still had low amino acid levels during the light training period were reanalysed after three weeks of additional protein intake. RESULTS: (1) The pre-Olympics amino acid patterns were as follows. Group A had a normal amino acid pattern (glutamine 554 (25.2) micromol/l, histidine 79 (6.1) micromol/l, total amino acids 2839 (92.1) micromol/l); all results are means (SEM). By comparison, both groups B and C had decreased plasma glutamine (average 33%; p<0.001) with, especially in group B, decreased histidine, glucogenic, ketogenic, and branched chain amino acids (p<0.05 to p<0.001). None in group A, one in group B, but ten athletes in group C presented with infection: all 11 athletes had plasma glutamine levels of less than 450 micromol/l. No intergroup differences in haematological or other blood biochemical parameters, apart from a lower plasma creatine kinase activity in group C than in group B (p<0.05) and a low neutrophil to lymphocyte ratio in the athletes with viral infections (1.2 (0.17)), were found. (2) During post-Olympic light training, group A showed no significant amino acid changes. In contrast, group B recovered normal amino acid levels (glutamine 528 (41.4) micromol/l, histidine 76 (5.3) micromol/l, and total amino acids 2772 (165) micromol/l) (p<0.05 to p<0.001) to give a pattern comparable with that of group A, whereas, in group C, valine and threonine had increased (p<0.05), but glutamine (441 (24.5) micromol/l) and histidine (58 (5.3) micromol/l) remained low. Thus none in group A, two in group B, but ten (53%) in group C still had plasma glutamine levels below 450 micromol/l, including eight of the 11 athletes who had presented with infection. (3) With the additional protein intake, virtually all persisting low glutamine levels increased to above 500 micromol/l. Plasma glutamine rose to 592 (35.1) micromol/l and histidine to 86 (6.0) micromol/l. Total amino acids increased to 2761 (128) micromol/l (p<0.05 to p<0.001) and the amino acid pattern normalised. Six of the ten athletes on this protein intake returned to increased training within the three weeks. CONCLUSION: Analysis of these results provided contrasting plasma amino acid patterns: (a) a normal pattern in those without lasting fatigue; (b) marked but temporary changes in those with acute fatigue; (c) a persistent decrease in plasma amino acids, mainly glutamine, in those with chronic fatigue and infection, for which an inadequate protein intake appeared to be a factor.

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Research works printed but not linked: 4

  1. Douglas DJ, Hanson PG. Upper respiratory infections in the conditioned athlete. Med Sci Sports Exerc 1978;10:55.
  2. Peters EM, Bateman ED. Ultramarathon running and upper respiratory tract infections. S Afr Med J 1983;64: 582-4.
  3. Burke D, Alverdy JC, Aoys E, et al. Glutamine supple- mented TPN improves gut immune function. Arch Surg 1989;124:1396-9.
  4. Kingsbury, Kay, Hjelm on August 20, 2023 by guest. Protected by copyright. http://bjsm.bmj.com/ Br J Sports Med: first published as 10.1136/bjsm.32.1.25 on 1 March 1998. Downloaded from

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Authors
Kingsbury, K. J., Kay, L., & Hjelm, M.
Venue
British Journal of Sports Medicine
Publisher
BMJ
Published
1998-03
Volume
32
Issue
1
Pages
25-32
ISSN
  • 0306-3674 (ISSN-L)
  • 1473-0480
DOI
10.1136/bjsm.32.1.25
PMC
PMC1756055
OpenAlex
W2166826211
Cited by
69
References
45
Citations by year
2024: 4 · 2023: 1 · 2022: 2 · 2021: 6 · 2020: 1 · 2019: 5 · 2018: 3 · 2017: 5 · 2016: 1 · 2015: 4 · 2014: 3 · 2013: 5 · 2012: 5
FWCI
0.72
Type
journal article
Language
en
Open access
Locations
  • British Journal of Sports Medicine (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Muscle metabolism and nutrition
  • Health Sciences › Medicine › Rehabilitation › Exercise and Physiological Responses
  • Health Sciences › Medicine › Orthopedics and Sports Medicine › Sports Performance and Training
Keywords
plasma free amino acids, elite athletes, exercise fatigue, glutamine, histidine, branched-chain amino acids, protein intake, health screening, creatine kinase, neutrophil-to-lymphocyte ratio, viral infection, judo, track and field, rowing, training load
MeSH terms
Amino Acids, Dietary Proteins, Fatigue, Humans, Sports, Track and Field, Nutrition Assessment, Martial Arts, Dietary Supplements

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