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Sports Medicine
Published in: Sports Medicine 10/2003

01-08-2003 | Review Article

Elucidating the Unexplained Underperformance Syndrome in Endurance Athletes

The Interleukin-6 Hypothesis

Author: Dr Paula J. Robson

Published in: Sports Medicine | Issue 10/2003

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Abstract

The unexplained underperformance syndrome (UPS), previously known as the overtraining syndrome (OTS), has been defined as a persistent decrement in athletic performance capacity despite 2 weeks of relative rest. It has been proposed that UPS may be caused by excessive cytokine release during and following exercise causing a chronic inflammatory state and ‘cytokine sickness’. This article extends that hypothesis by proposing that time-dependent sensitisation could provide a model through which the aetiology of UPS may be explained. In this model, the principal abnormal factors in UPS are an increased production of and/or intolerance to interleukin (IL)-6 during exercise. Strategies to attenuate the IL-6 response to exercise that may also reduce an athlete’s susceptibility to UPS are proposed.
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Metadata
Title
Elucidating the Unexplained Underperformance Syndrome in Endurance Athletes
The Interleukin-6 Hypothesis
Author
Dr Paula J. Robson
Publication date
01-08-2003
Publisher
Springer International Publishing
Published in
Sports Medicine / Issue 10/2003
Print ISSN: 0112-1642
Electronic ISSN: 1179-2035
DOI
https://doi.org/10.2165/00007256-200333100-00004