Effects Of Menstrual Cycle Phases And Incremental Exercise On Blood Lactate And Salivary Cortisol

Abstract

PURPOSE: The purpose of this investigation was to examine circamensal variations and incremental exercise effects on blood lactate and salivary cortisol concentrations. METHODS: Fifteen eumenorrheic athlete females (Mean ± SD age: 21.9 ± 2 years, weight: 58.4 ± 4.6 kg, height: 161.7± 4.2 cm) participated in this study. They were tested during two phases of the menstrual cycle (the mid-follicular and the mid-luteal) at 7:00 a.m. Blood and salivary samples were obtained for analysis. For cortisol assessment, samples were obtained from the tip of their index finger and analyzed by lactometer before (rest) and immediately after incremental test on a cycle ergometer. All subjects completed consent form. This study was approved by University of Isfahan Ethic Committee. RESULTS: No significant circamensal variations were observed in blood lactate (F=0.14, P>0.05) and salivary cortisol concentrations (F=0.29, P>0.05 (before and immediately after incremental test on cycle ergometer. Lactate concentration was significantly increased in both follicular and luteal phases, after incremental exercise (F= 148.2, P<0.05). However, the mean salivary cortisol level was not significantly affected by incremental exercise (F=1.09, P>0.05) in both phases. In addition, no significant correlation was found in lactate and cortisol before and after incremental exercise across the menstrual cycle phases (Table 1).TABLE 1: Lactate and cortisol concentrations at follicular and luteinize phases (N= 15)CONCLUSION: The findings of this study suggest that there are no circamensal variations in lactate and cortisol concentrations before or after incremental exercise.