American Journal of Sports Science and Medicine. 2013, 1(2), 17-27
DOI: 10.12691/AJSSM-1-2-2
Original Research

Overestimated Effect of Epo Administration on Aerobic Exercise Capacity: A Meta-Analysis

Hein F.M. Lodewijkx1, , Bram Brouwer1, Harm Kuipers2 and René van Hezewijk1

1Department of Psychology, Open University, Heerlen, The Netherlands

2Department of Movement Sciences, University of Maastricht, Maastricht, The Netherlands

Pub. Date: April 28, 2013

Cite this paper

Hein F.M. Lodewijkx, Bram Brouwer, Harm Kuipers and René van Hezewijk. Overestimated Effect of Epo Administration on Aerobic Exercise Capacity: A Meta-Analysis. American Journal of Sports Science and Medicine. 2013; 1(2):17-27. doi: 10.12691/AJSSM-1-2-2

Abstract

Recent studies examining the relationship between epo doping and aerobic performance (the EDAP–relationship) yield conflicting results. To resolve this inconclusiveness in an empirical way, we conducted a meta–analysis on 17 laboratory studies and assessed effect sizes (unbiased d, r and r2) of the epo–induced improvements in aerobic exercise capacity measured by maximal oxygen uptake (VO2max) and maximal aerobic power output (Wmap). The fixed, pooled EDAP effect size estimates were moderate, d = 0.41–0.49, r = .19–.44, and r2 = .04–.19, revealing a shift of approximately half SD in performances of the epo–treated compared to the non–treated participants. As to VO2max, we observed the strongest post test performance (M = 64.39ml kg-1 min-1) in double blind, placebo controlled studies on performances assessed at sea level with an increase from pre to post tests of M = 4.02ml kg-1 min-1. Regarding Wmap, the increase was M = 26W with the strongest post test performance of M = 398W observed in similar studies as VO2max. Percents improvement from pre to post tests varied between M = 6–7% (VO2max), and M = 7–8% (Wmap). The largest improvement in VO2max we found equals an increase in velocity of about 1km/h. Consistent with recent studies criticizing the EDAP-relationship our findings indicate that its strength is overestimated. In turn, this entails that the relationship between epo doping and cyclists’ performances at real contests is overrated too.

Keywords

aerobic performance, epo doping, meta-analysis, professional road racing

Copyright

Creative CommonsThis work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

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