Reduced Triiodothyronine (T3) Levels are Associated With Decreased Physical Performance in Female Collegiate Rowers: A Case-Control Report
Abstract
Background: Even though women’s rowing has been an Olympic sport for nearly 50 years, it is an understudied topic in female physiology. This oversight is critically important in lieu of the serious health consequences to the training athlete from conditions such as the Female Athlete Triad or Relative Energy Deficiency in Sport. As such, the current study was undertaken to examine hypothalamic-pituitary-thyroidal hormones and select other blood biomarkers (e.g. immune) in female rowers over the course of a 20-week training cycle, to determine whether changes in these parameters differed in athletes whose physical performance varied (improved vs. became worse) during the cycle.
Methods: The approach herein was to conduct a single-subject experimental design in a case-control fashion. A number of biomarkers were assessed at the beginning and end of the 20-week training cycle, as was physical performance via a 2,000-meter time trial (ergometer).
Results: The major finding was that development of a euthyroid sick syndrome-like scenario existed in the female rower who had physical performance compromise (decline) at the end of a 20-week training cycle.
Conclusion: It is hypothesised that the major hormonal outcome of this study, low triiodothyronine (T3) levels, is a plausible major factor for inducing a maladaptive training response in the athlete with performance decline during the study.
Keywords: Athletes, women, euthyroid sick syndrome, sport, REDs, overtraining, biomarkers
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