Validating the salivary testosterone and cortisol concentration measures in response to short high-intensity exercise
Crewther, BT, Lowe, TE, Ingram, J & Weatherby, RP 2010, 'Validating the salivary testosterone and cortisol concentration measures in response to short high-intensity exercise', The Journal of Sports Medicine and Physical Fitness, vol. 50, no. 1, pp. 85-92.
AIM: To validate the testosterone (T) and cortisol (C) concentration measures in saliva in response to short high-intensity exercise.
METHODS: Nine healthy males provided matching saliva and plasma samples before and after a 30-second Wingate cycle test. Saliva was assayed for T (Sal-T) and C (Sal-C) concentrations, and plasma for total T and total C, sex hormone-binding globulin, corticosteroid-binding globulin (CBG) and albumin concentrations. The plasma free and bioavailable hormones were calculated.
RESULTS: The Sal-T and plasma T correlations were weak to moderate (r=0.57-0.61) when examined between individuals (pooled data for all participants), but these relationships improved (r = 0.71-0.73) within individuals (data for each participant on average). The Sal-C and plasma C correlations were strong both between individuals (r=0.81-0.84) and within individuals (r=0.83-0.84). The peak relative increases in Sal-T (35±9%) and Sal-C (63±29%) concentrations exceeded the plasma total and/or free hormones, but not the bioavailable hormones. Albumin (10±3%) and CBG (16±4%) also increased with exercise, along with blood lactate (943±119%).
CONCLUSION: The Sal-T and Sal-C concentration measures were validated in response to short high-intensity exercise, especially for individuals. The hormonal changes in saliva were also more sensitive to exercise (i.e. greater relative responses) than the plasma total and/or free hormones, potentially arising from changes in the binding proteins and blood lactate. These findings support the use of saliva as a medium for steroid determination in sport.