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Background: The present study was performed to clarify fatigue-induced effects of a strenuous and moderate intensity endurance training session on temporary changes of cardiopulmonary (CP) chemosensitivity and fast kinetics response. Material/Methods: Eleven high performance (national level) male rowers participated in this study [age 21.8 ±1.7 (range 18-25 years), 89.3 ±2.0 kg, 190.1 ±1.7 cm, VO2 max 67.9 ±1.1 ml·kg-1·min-1]. The studies involved three steps: 1) a study of effects related to a training session of moderate intensity, 2) effects of a high intensity session, and 3) an impact of a high intensity session on values of peak response. The high intensity session consisted of intermittent training loads made up of five sets of four repetitions of sixty-second work intervals (HR of 149-186 bt·min-1). The moderate intensity session consisted of unvarying type of exercise (HR of 138-167 bt·min-1). Measurements were made at rest before, 13-15, and 37-39 hours after the training session. In rebreathing tests ventilatory sensitivity to CO2 and HR response sensitivity to normocapnic hypoxia were measured. Fast kinetics of ventilation, oxygen uptake, CO2 production and the heart rate were measured in a 5-min standard power test (0.7 VO2 max, 5 min, transition from 25 w) and in a 6-min test (1.12 ±0.11 VO2max). Results: We found that a training session of high intensity resulted in a significant decrease in sensitivity to hypercapnia, an increase in CP sensitivity to hypoxia, a decrease in CP fast kinetics and stability of peak response 13-15 hours after the session vs. baseline. Mean power in a 6-min maximum test decreased, which was mainly determined by a decrease in mean power during the first 3 min and utilization of VO2 max for a 6-min test. Moderate intensity of a training session resulted in an increase in ventilatory sensitivity to hypercapnia whereas sensitivity CP to hypoxia and fast kinetics remained unaffected. Conclusions: These results suggest that not only CP chemosensitivity to hypoxia but also CP chemosensitivity to hypercapnia are variable in high intensity endurance training. The variability related to the effect of fatigue in the recovery phase (up to 15-15 hours) after strenuous training sessions.
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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