Salivary testosterone and cortisol concentrations after two different resistance training exercises

Area of Science:

• Exercise Physiology
• Endocrinology
• Sports Science

Background:

• Understanding acute hormonal responses to resistance training is crucial for optimizing athletic performance and recovery.
• Salivary testosterone (T) and cortisol (C) are key biomarkers of the stress and anabolic response to exercise.

Purpose of the Study:

• To investigate the acute hormonal changes in salivary testosterone and cortisol following lower-body (back-squat) versus upper-body (bench press) resistance exercises.
• To compare the T/C ratio as an indicator of hormonal balance after different resistance training protocols.

Main Methods:

• 13 recreationally trained males completed a standardized resistance training protocol (5x10 reps, ~75% 1RM) for both bench press and back-squat exercises in a cross-over design.
• Saliva samples were collected at baseline, mid-training, immediately post-training, and 45 minutes post-training.
• Samples were analyzed for testosterone and cortisol concentrations, and the T/C ratio was calculated.

Main Results:

• Back-squat exercise led to significant increases in salivary T and C concentrations post-exercise.
• Bench press exercise did not produce significant changes in salivary T or C concentrations.
• The T/C ratio increased immediately after back-squat but decreased by 45 minutes post-exercise.

Conclusions:

• Intense lower-body resistance exercise, specifically the back-squat, significantly alters acute hormonal profiles (T and C).
• Upper-body exercises involving less muscle mass, like the bench press, have a negligible impact on these acute hormonal responses.
• The findings suggest exercise selection plays a critical role in modulating hormonal responses to resistance training.