Growth and pubertal development in adolescent male wrestlers.

BACKGROUNDː Adolescence is a crucial period for linear growth, and sports training during this time may have positive or negative effects on some physiological processes as growth. The purpose of this study was to evaluate the effects of intense training during somatic growth on the onset of puberty and growth development in adolescent wrestlers. METHODS: Fifty adolescent male wrestlers and twenty-one sedentary healthy male controls aged between 13-15 years were selected. The wrestlers were from five different wrestling schools and were active at competitive level. The maturity status of the subjects and data about the anthropometric characteristics including age, body weight, height, and Body Mass Index (BMI) were evaluated. Serum testosterone, dehydroepiandrosterone sulphate, follicle stimulating hormone, luteinizing hormone, prolactin, cortisol, insulin like growth factor-1 (IGF-1), thyroid stimulating hormone (TSH) and free thyroxin were determined. RESULTS: Anthropometric characteristics and puberty levels according to the Tanner stage were similar in both groups. There were no significant differences between wrestlers and sedentary control groups in sex hormones, cortisol, IGF-1, prolactin levels (P>0.05) but TSH concentrations differed significantly (P=0.015). CONCLUSIONS: The results suggested that training in adolescent male wrestlers did not significantly change resting sex hormones or alter the onset of puberty as determined by assessment of pubertal stages. The wrestlers had lower body fat and greater energy expenditure per week, there were no significant differences in height, weight, or BMI.

The effect of exercises on left ventricular systolic and diastolic heart function in sedentary women: Step-aerobic vs core exercises.

The purpose of this study is to investigate the effect of 16 weeks step-aerobic exercises and core exercises on left ventricular structure and function with some physiological parameters in sedentary women. METHODS: To achieve the purpose of this study, a total of 45 volunteers including (step-aerobic group (SAG, n = 25), core exercise group (CEG, n = 20) were selected as participants. Two different exercises were applied for 4 days a week, throughout 16 weeks, within 60 minutes for each exercise with the intensity of heart rate (HR) 60-70 percent. The HR was measured using a heart rate monitor for each subject. The physical, biochemical and echocardiographic characteristics of the women were measured before and after the exercise. RESULTS: During the exercise periods, there were a meaningful decrease in the body weight, BMI, value of waist region and hip circumference of the women in both intervention groups as well as in the values of HR, DBP, SBP (p < 0,05). In addition, serum homocysteine (Hcy) and high-sensitivity C-reactive protein (Hs-CRP) levels decreased and the VO2max and left ventricular diastolic end-diastolic dimension increased in both SAG and CEG (p < 0.05). The left ventricular diastolic functions of the SAG improved more than CEG. Left ventricular systolic ejection time and fractional shortening meaningfully improved in both SAG and CEG (p < 0.01). CONCLUSION: 16 weeks of step-aerobic and core exercise showed significant changes of inflammatory and lipid markers with cardiac dimensions and had favorable effects on both left ventricular systolic function. Left ventricular diastolic function had more improved in SAG than the CEG.

The effects of two different exercise programmes on adipose tissue hormones in sedentary middle-aged women.

Adipokines play an important role in obesity and related inflammatory disorders. We aimed to determine the effects of exercise training on serum adipokines. Forty sedentary women were randomly assigned to two groups as aerobic (AE) and core exercise (CE). The exercise programmes were performed 4 days a week for 16 weeks. Blood samples were taken before and after the 8 and 16 weeks training period. Percent changes of each parameter were calculated. Sixteen weeks of exercise caused significant decrease in body weight and fat mass (p < 0.001), significant increase in adiponectin (16.1% in AE, 15.8% in CE group, p < 0.05) and resistin levels (21.1% in AE and 26.6% in CE group, p < 0.05) but had no effect on leptin and ghrelin levels. Eight weeks of exercise had no effect on adipokines except leptin. These data suggest that both exercise programmes have improving effects on body composition, adiponectin and resistin levels.

Gonadal function in male mountain bikers.

Some studies reported testicular disorders associated with biking in mountain cyclists, which include injuries, erectile dysfunction, and higher scrotal temperatures. But none of these studies evaluated gonadal function. Therefore, the aim of this study was to evaluate gonadal function in male mountain bikers. Twenty-two male professional mountain bikers and 30 healthy noncyclist controls were included in the study. The mean age and body mass index were similar in both groups. Fasting blood samples for the measurement of the levels of total testosterone (TT), sex-hormone binding globulin (SHBG), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were obtained from all study participants before any physical activity. In addition, because insulin sensitivity and leptin modulate gonadal function, the concentrations of insulin, glucose, and leptin were also measured in the same samples. Calculated free testosterone (cFT) and bioavailable testosterone (bioT) were calculated from SHBG and TT. Basal hormonal levels including insulin, leptin, LH, FSH, SHBG, TT, glucose, and homeostasis model assessment scores were similar between the groups. However, bioT and cFT levels were significantly lower (p ≤ 0.05) in the mountain bikers than those in the controls. Despite the lower mean testosterone levels in the study group, the levels of LH and FSH were similar to controls. Insulin and leptin do not contribute to lower testosterone levels. In conclusion, male mountain bikers have lower testosterone concentrations compared to controls. This alteration cannot solely be explained by testicular dysfunction. The etiology of lower testosterone levels in cyclists appears to be complex and requires further research. The influence of such a decline on the athlete's performance, quality of life, and muscle strength is not known as yet.