Serum leptin concentration and anaerobic performance do not change during the menstrual cycle of young females.

OBJECTIVES It was aimed to determine whether there was a difference in the leptin levels and short term exercise performance during the menstrual cycle of the young females who had normal menstrual cycle and no pregnancy story. SETTING AND DESIGN Fifteen sedentary females aged 19-23 yrs were included. All had regular menstrual cycle of 28-30 days and no pregnancy story. Blood samples were taken for the analysis of serum estradiol, progesterone and leptin levels and Wingate test was applied on a Monark 818E ergometer with 75 g/kg load on the 7th, 14th and 21st cycle days, randomly. RESULTS The differences in serum leptin levels and peak power, mean power and fatigue index during these days and the correlations between serum leptin and FSH, LH, estradiol and progesterone levels were not significant. CONCLUSIONS We concluded that performance in a short intense exercise which require high motivation is not affected by menstrual cycle and in young females with normal menstrual cycle, serum leptin concentration does not change during the cycle. Further studies constituting more standard groups, controlling food intake, timing the blood sampling, studying more days of menstrual cycle will help to obtain more accurate results.