evaluation of the alterations in blood cortisol and triglyceride levels in endurance athletes in comparison with controls

introduction exercise is associated with an increase in cortisol - the most important hormone in fat metabolism. cortisol levels vary during a day. this study was conducted in view of the lack of any documents on cortisol levels in endurance athletics in iran. methods in a cross-sectional study, 25 male endurance runners age 18-25 years and 25 non-athlete men were selected. the cortisole and tg levels were analyzed using elisa in the morning and evening. t-test was used for statistical analysis and p<0.05 was considered as significant. results the cortisol level in athletes was 25±1.1 µg/dl in the morning and 12±1.5 µg/dl in the evening. the morning and evening cortisol levels in the control group were 11±2.7 µg/dl and 3±1.4 µg/dl, respectively. tg levels in athletes in the morning and evening were 80±6 µg/dl and 162±12 µg/dl, respectively. the morning and afternoon tg levels in the control group were 150±25 µg/dl and 200±34 µg/dl, respectively. all of the differences were statistically significant. conclusions fat burning is higher in endurance athletes including endurance runners because of higher levels of cortisol in the mornings than evenings. keywords endurance athletes, runner, cortisol, triacylglycerol.