The effects of one vs. two exhaustive sessions exercise on Cortisol, TNF-α and Adenosine Deaminase enzyme in endurance runners

Background:  The purpose of the present study was to examine whether a first bout of exhaustive exercise can change inflammo-endocrine responses to second subsequent similar exercise on the same day.  Cortisol, TNF-α, and Adenosin Deaminas Enzyme (ADA) were assessed during a progressive endurance protocol.

Methods: Eight well trained endurance runners (aged 23.13±3.39 years; weight, 66.21±9.47 kg; Height 175.29±10.12 cm, and BMI 21.4±1.54 kg/m²), participated in a design with three following trials: 1) control condition day (rest)(C); 2) one bout of exhaustive exercise on a day (between the hours of 15.30-17)(E1); and 3) two bouts of exhaustive exercise on a day with 4 h rest between them (between the hours of 10-11.30 and again 15.30-17)(E2). Blood samples were drawn before exercise, immediately after exercise and 4 h post exercise from anterior median cubital vein.

Results: The results of the present study, using two way repeated ANOVA, showed that salivary Cortisol increased significantly, in both E1 and E2 situations (p<0.05). In this respect, there was no difference between exercise (E1 and E2) with respect to control condition. Exercise-induced increase of TNF-α was only significant during two bouts of exhaustive exercise on a day (E2) (p<0.05). The ADA enzyme activity did not alter in various conditions.

Conclusion: Increasing aerobic exhaustive exercise sessions in a day can enhance the amount of inflammation, though; these alterations are not caused by Cortisol.