Objectives: To determine the association between the nuclear respiratory factor 2 (NRF-2) polymorphisms and elite athletic performance. Design: We compared the genotype and allele frequencies of the NRF-2 A/C (rs12594956), NRF-2 A/G (rs7181866), and NRF-2 C/T (rs8031031) polymorphisms between world-class endurance athletes (n = 89), elite power-oriented athletes (n = 38), and non-athletic controls (n = 110) of the same Caucasian (Spanish) origin. Methods: Genomic DNA was extracted from peripheral EDTA-treated, anti-coagulated blood using a standard protocol. Genotyping was performed using polymerase chain reaction (PCR). Results: The frequency of the AA genotype of the NRF-2 A/C (rs12594956) polymorphism was significantly higher in endurance athletes compared with power athletes (P < 0.01) and controls (P < 0.01) (48% vs. 13% and 21%, respectively). The likelihood of having the AA (rs12594956) genotype was higher in elite endurance athletes compared with controls [odds ratio (OR): 3.536, 95% confidence interval (CI): 1.903-6.571] and elite power athletes (OR: 6.170, 95%CI: 2.206-17.253). Conclusions: Our results suggest that the NRF-2 A/C polymorphism might belong to a growing group of polymorphisms associated with endurance performance at the elite level. However, it is important to replicate these findings in other groups of elite athletes using larger sample sizes. (C) 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.