QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Newsholme, E. A. Articles by Blomstrand, E. Search for Related Content PubMed PubMed Citation Articles by Newsholme, E. A. Articles by Blomstrand, E.

---

Branched-Chain Amino Acids: Metabolism, Physiological Function, and Application: Session III

Branched-Chain Amino Acids and Central Fatigue^1–3,

Eric A. Newsholme^* and Eva Blomstrand^,**,4

^* Merton College, Oxford, UK, University College of Physical Education and Sports, and ^** Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden

⁴ To whom correspondence should be addressed. E-mail: eva.blomstrand{at}gih.se.

ABSTRACT

An account of the tryptophan (Trp)–5-hydroxytryptamine (5-HT)–central fatigue theory is provided and an explanation of how oral administration of BCAAs can decrease fatigue on the basis of this theory is given. The rate-limiting step in the synthesis of 5-HT is the transport of Trp across the blood–brain barrier. This transport is influenced by the fraction of Trp available for transport into the brain and the concentration of the other large neutral amino acids, including the BCAAs, which are transported via the same carrier system. During endurance exercise, there is an uptake of Trp by the brain, suggesting that this may increase the synthesis and release of 5-HT in the brain. Oral intake of BCAAs may reduce this uptake and also brain 5-HT synthesis and release, thereby delaying fatigue. Other hypotheses for the effect of BCAAs on central fatigue are included.

KEY WORDS: • branched-chain amino acids • 5-hydroxytryptamine • tryptophan

This article has been cited by other articles:

				M. Amann and J. A. Dempsey Locomotor muscle fatigue modifies central motor drive in healthy humans and imposes a limitation to exercise performance J. Physiol., January 1, 2008; 586(1): 161 - 173. [Abstract] [Full Text] [PDF]

				M. Amann, L. M. Romer, A. W. Subudhi, D. F. Pegelow, and J. A. Dempsey Severity of arterial hypoxaemia affects the relative contributions of peripheral muscle fatigue to exercise performance in healthy humans J. Physiol., May 15, 2007; 581(1): 389 - 403. [Abstract] [Full Text] [PDF]

				J. L. Ryan, J. K. Carroll, E. P. Ryan, K. M. Mustian, K. Fiscella, and G. R. Morrow Mechanisms of Cancer-Related Fatigue Oncologist, May 1, 2007; 12(suppl_1): 22 - 34. [Abstract] [Full Text] [PDF]

				L. Cynober and R. A. Harris Symposium on Branched-Chain Amino Acids: Conference Summary J. Nutr., January 1, 2006; 136(1): 333S - 336S. [Full Text] [PDF]