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Background. This study was focused on investigations of secondary regulators of plasma leptin levels such as prolactin, testosterone, sex hormone binding globulin (SHBG) and nutritional status, in young female athletes with menstrual disorders. Material and methods. Thirty four female professional rowers with menstrual disorders (iamenorrhoea and oligomenorrhoea), aged 18.1 ±2.0, with a training period of 4.3 ±2.1 and BMI of 21.0 ±2.1 kg/m2, with too high (IL) or too Iow plasma leptin levels (DL) participated in the study. The nutritional status was evaluated based on the analysis of body composition using the BIA method - percentage of adipose tissue (FM) and fat free mass (FFM) and skinfold thickness (ST) using a Harpenden skinfold caliper. Moreover, serum levels of leptin, prolactin, testosterone and SHBG were estimated using RIA kits. Results. Values of BMI, ST, FM were significantly (p < 0.05) higher in IL athletes, while FFM was significantly (p < 0.05) lower compared to DL rowers (BMI: IL 22.3 ±2.2 kg/m2, DL 20.2 ±1.4 kg/m2, ST: IL 12.4 ±4.0 mm, DL 9.5 ±2.1 mm, FM: IL: 23.2 ±4.9%, DL: 19.3 ±3.3%, FFM: IL 76.8 ±4.9%, DL 80.7 ±3.4%). The results of plasma leptin level correlated (p < 0.05) with anthropometric parameters (age: r = -0.38, body mass: r = 0.46, BMI: r = 0.59, ST: r = 0.40), body composition (FM%: r = 0.48, FM kg: r = 0.55, FFM%: r = -0.48), prolactin (r = 0.72) and testosterone levels (r = 0.43). Conclusions. The results confirmed the strong influence of body mass and fat mass on serum leptin levels. However, high prolactin and testosterone levels may also favourably increased plasma leptin levels in athletes and also affect menstrual disorders.
Background. Some factors which have been considered to be responsible for female athlete triad include the specific type and amount of high intensity training in young female athletes (especially when begun before puberty), reduced body weight, a lower percentage of fat tissue, and psychological stress. The aim of this study is to estimate the risk of amenorrhoea in female athletes with menstrual irregularity, on the basis of body composition results, nutritional factors, and endocrine factors. Material and methods. Fifty-five female professional athletes with menstrual irregularities, of mean ages 17.9 ±2.1 years, with mean training histories of 5.8 ±2.6 years, and BMIs of 20.6 ±1.4 kg/m2 participated in the study. The first group (ED) included athletes from endurance disciplines (n = 30), while the second group (WD) consisted of females from weight category disciplines (n = 25). A second classification was also employed, distinguishing between the group of athletes (IH) with luteinizing hormone to folliclestimulating hormone ratio LH/FSH < 0.6 (n = 24) - diagnosed as hypofunction of the hypothalamus-pituitary axis - and a second group (GR) containing athletes with LH/FSH > 0.6, diagnosed as a good result (n = 31). Nutritional status was evaluated on the basis of body composition analysis using the BIA method employing a Harpenden skinfold callipers, which yielded measurements of the percentage of adipose tissue (FM), fat-free mass (FFM), and skinfold thickness (AST). Nutritional values were estimated by examining dietary records for 7 consecutive days, and using threefold recall for the last 24 h. Moreover, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E), progesterone (P), and serum leptin levels were measured. Results. Significant differences were found between the hormone levels of for each discipline group: for LH, the ED group had 3.6 ±2.5 mlU/ml, and the WC group had 5.4 ±2.4 mlU/ml (p < 0.05), while for FSH, the values were ED: 5.0 ±1.8 mlU/ml, WC: 6.3 ±1.5 mlU/ml 224 (p < 0.05). Furthermore, IH athletes had significantly lower LH levels compared with GR athletes (IH: 2.8 ±0.9 mlU/ml, GR: 6.2 ±2.7 mlU/ml, p < 0.05). FSH, LH, LH/FSH, and leptin levels were positively correlated with energy and intake of most nutrients. These results again confirm the strong influence of anthropometric parameters (BMI: r = 0.85, ST: r = 0.43, p < 0.05), body composition (FM%: r = 0.79, FFM%: r = -0.79, p < 0.05), and age at menarche (r = -0.39, p < 0.05) on serum leptin levels in IH athletes. Conclusion. Improperly balanced diets, low fat mass, and low leptin levels are factors which predispose to amenorrhoea. Furthermore, a gonadotropin level suggestive of hypothalamic-pituitary axis hypofunction, and positively correlated with energy intake and with leptin level, is a further factor conducive to amenorrhoea.
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