Monitoring salivary testosterone and cortisol concentrations across an international sports competition: Data comparison using two enzyme immunoassays and two sample preparations

Objectives: Salivary testosterone (T) and cortisol (C) concentrations were monitored across a sports competition. Data were compared using two enzyme-immunoassay (EIA) methods and two sample preparations to determine their influence on hormone concentrations. Design and methods: A group of male athletes (n = 19) provided a saliva sample the morning before and one day after (24 h post) an international rugby union match. Following an extraction procedure, the samples were analysed for T and C concentrations using a commercial kit (CME) and an in-house method (IHE). Raw samples (no extraction procedure) were also tested using the commercial kit (CMR). Results: There were no significant changes in T and C levels from pre to post competition with each EIA method and sample preparation, but significant differences in T ((IHECME)-C->>CMR) and C (CMR>IHE and CME) concentrations were seen when both samples were pooled. Bland-Altman analyses confirmed the presence of fixed and proportional bias. Strong and significant correlations were demonstrated between the IHE and CME measures of salivary T (r = 0.93-0.97) and C (r = 0.95-0.97). The T and C values from the raw and extracted samples were also strongly correlated (r = 0.93-0.96). Conclusions: The measurement of salivary T and C concentrations across an international sports event was influenced by different EIA methods and sample preparations, but all measures were strongly correlated with some bias. Both T and C were unresponsive to the sports event, but within the group results large individual variation was seen. (C) 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.