The relationship between the cortisol awakening response, mood states, and performance.

This study examined the variation in the diurnal profile of cortisol, with an emphasis on the cortisol awakening response (CAR), in relation to mood states and performance during a professional swimming contest. Eleven athletes were examined during 2 consecutive days of competition and during a recreated event 2 weeks later that was matched to the time of the day and day of the week of the competition. On each day, salivary cortisol was determined upon awakening (07:00 hours); 30 and 60 minutes post-awakening; immediately before warming up for competition (16:00 hours); and 5 minutes (18:20 hours), 20 minutes (18:40 hours), and 40 minutes (19:00 hours) after competition. Psychometric instruments included the Profile of Mood States and self-reports of performance. Cortisol awakening responses did not differ between days of competition and control and were not related to performance on any day. However, a difference was observed in the concentration of cortisol before and after the contest between the competition and control days. Higher levels of cortisol before competition were associated with feelings of tension, anxiety, and hostility. The perceived demands of the day ahead might not produce the same magnitude of variation in the CAR in well-trained men. Explanations for this probably include better coping mechanisms and responses to the phase and time of competition.

Determination of the lactate threshold by means of salivary biomarkers: chromogranin A as novel marker of exercise intensity.

This study examined intra-individual variations in salivary lactate (sLac), alpha-amylase (sAA) and chromogranin A (sCgA) with reference to the accumulation of blood lactate (bLac) during incremental maximal exercise in swimmers. Samples of blood and saliva were collected simultaneously from 12 male professional athletes during an incremental test that consisted of eight series of 100 m in front crawl with increasing velocity (0.03 m s(-1) each) and 70-s intervals. The concentration of blood and salivary lactate was determined by an electro-enzymatic assay, whereas sAA and CgA were analysed by Western blotting. Inflection points in the concentration of bLAc, sLac, sAA and CgA were found in all subjects. The accumulation of lactate in saliva followed the same pattern observed in blood with a high correlation between the two (r = 0.91). Similar results were observed between the dynamics of sAA (r = 0.81) and sCgA (r = 0.82) in relation to bLac. These findings support the usefulness of saliva for the determination of the lactate threshold and provide the first demonstration of sCgA as a novel marker of exercise intensity in well-trained men.