The influence of exercise on growth hormone and testosterone in prepubertal and early-pubertal boys

Abstract

The purpose of this study was two fold a) to determine the levels of hormonal parameters which are related to growth and sexual maturation (T, SHBG, .AI, GH) in 66 pre-pubertal and early-pubertal boys (11-13 years old) who systematically engage in individual and team sports activities of endurance, strength, speed and skill, respectively, and b) to investigate the effect of two different forms of exercise namely aerobic (AG) and weight training (WG) on androgen levels in 19 sedentary pre-pubertal boys. The control groups (CG) consisted of boys of the same age who attended only the school physical education programmes. The individuals included in the study participated voluntarily after their parents had been informed and had given their written consent. Hormonal concentrations were determined using radioimmunoassay and immunoradiometric assays. No differences were observed among the various athletes groups as regards Tanner stages, height and weight. The mean T and .AI values of the control group did not differ from those of the corresponding athletes group. Significant differences were observed among the groups regarding BMI, % body fat, T, SHBG, .AI and GH (p<0.05). T and .AI values in the WG group were significantly higher than the corresponding concentrations: a) in the AG group by 338 and 609%, p<0.05 and b) in the control group CG by 91 and 96%, p<0.05, respectively. The hormonal differences detected among the various groups of athletes must be attributed as much to the type of physical exercise and to developmental factors as to the selection criteria used for the different athletic talents. The importance of the specificity of training stimulus in the hormonal adaptations of pre-pubertal sedentary subjects was demonstrated.

Olfactory Stimulation by Fennel (Foeniculum vulgare Mill.) Essential Oil Improves Lipid Metabolism and Metabolic Disorders in High Fat-Induced Obese Rats

“…Group H showed the highest level of insulin; however, group H had a lower length gain than the FEO-inhaled groups. The FEO-inhaled groups showed lower insulin resistance than group H. A previous study showed that body weight, body fat, and insulin levels were decreased by aerobic exercise, as well as increased GH and IGF-1 levels [27]. According to a previous study and the results of this study, insulin secretion and insulin resistance may indirectly induce an increased length gain, while increasing insulin resistance, which is affected by the excessive secretion of insulin, is one of the inhibitory factors of growth [1,27].…”

Androgen Responses to Sprint Exercise in Young Men

“…These results are in accordance with previous studies that observed no change in the basal plasma free testosterone and TT concentrations after resistance training in adolescent handball [11] and soccer players [12] . However, others studies have also reported an elevation of the basal TT levels in adolescent males in response to shorter physical training programs (i. e., 2 -3 months) that included heavy resistance training [34] and intense endurance training sessions [35] . These latter results suggest that training intensity and volume in our study would be insuffi cient to increase basal plasma testosterone concentrations.…”

The Influence of Physical Training on Blood Levels of Human Growth Hormone, Testosterone and Procollagen in Young Rowers

“…According to Hartley (1975) and Bunt et al (1986), GH levels increase during training period. Tsolakis et al (2003) found significant differences in T and GH among athletes group (handball, rowing, running, basketball, fencing etc.). The mean T of the control group (sedentary boys) did not differ from those of the corresponding exercise group.…”

“…The mean T of the control group (sedentary boys) did not differ from those of the corresponding exercise group. The study by Tsolakis et al (2003) demonstrated the importance of the specificity of the training stimulus in the hormonal adaptations of pre-pubertal sedentary subjects.…”