The levels of testosterone secretion during the post-awakening period in men

The levels of testosterone secretion during the post-awakening period were determined in saliva samples collected from adult men (aged 24-80 years). The participants of this study can be classified into two subgroups based on their CARi (CARi = Cortisol levels at 30 min after awakening - Cortisol levels immediately upon awakening ) . Typical CAR (i.e., CARi > 2.5 nmol/L) was observed in 155 participants (participants exhibiting typical CAR). No typical CAR, either less than a 2.5 nmol/L increase or the complete absence of a post-awakening increase (i.e., negative CAR), was found in 70 participants (participants exhibiting no typical CAR).