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.