Reticulocyte and haemoglobin profiles in elite triathletes over four consecutive seasons

Area of Science:

• Sports Science
• Anti-Doping Research

Background:

• The World Anti-Doping Agency uses the Blood Passport to detect blood doping.
• The passport monitors changes in reticulocyte percentage (Ret %) and haemoglobin concentration ([Hb]).
• Limited research exists on the long-term stability of Ret % and [Hb] in athletes undergoing intense exercise.

Purpose of the Study:

• To assess the concurrent stability of Ret % and [Hb] in elite triathletes over four competitive seasons.
• To validate the use of these parameters for anti-doping purposes.

Main Methods:

• Measurements of Ret % and [Hb] were taken from elite triathletes (10 males, 7 females) over four seasons.
• Blood samples were collected at multiple points within each season: start, precompetitive, competitive, and end of the season.

Main Results:

• Significant differences in [Hb] and Ret % were observed between genders, with high inter-subject variability.
• No significant differences in [Hb] were found across seasonal periods for either gender.
• Ret % showed significant variation between periods only in female athletes within a season.

Conclusions:

• Ret % and [Hb] demonstrate stability over four seasons in elite triathletes, supporting their use in Blood Passport anti-doping strategies.
• Further investigation into seasonal Ret % fluctuations in female athletes is warranted.