The Impact of Macronutrient Intake on Sex Steroids During Onset of Puberty

Effects of 8-week strength training on basal hormone levels, sex hormone binding globulin, insulin-like growth factor binding protein-3, oxidative stress markers, and IL-6 levels in adolescent athletes

PURPOSE

The aim of the study was to investigate how 8-week strength training affects adolescent athletes' basal hormone concentrations, sex hormone binding globulin (SHBG), insulin-like growth factor binding protein-3 (IGFBP-3), cytokine, and oxidative stress markers.

METHODS

Twenty adolescent handball players participated in this study. The participants were randomly divided into the strength training group (ST, n = 10) and the control group (C, n = 10). ST participates in strength training 3 sessions a week for 8 weeks and C participates only in handball training. We quantified serum basal hormone concentration, SHBG, IGFBP3, oxidative stress markers, and IL-6 in each subject's blood samples before and after 8 weeks of strength training.

RESULTS

Interestingly, while insulin-like growth factor-1 (IGF-1) concentration declined in group C (p < 0.05), it did not in ST (p > 0.05). Furthermore, the basal concentration of growth hormone (GH), total testosterone (T), cortisol (Cor), total antioxidant status (TAS), and serum-free androgen index (FAI) basal concentration did not change in ST and C. Basal IGFBP-3 and SHBG concentrations decreased only in ST (p < 0.05), but not in C (p > 0.05). Serum-free testosterone (FT) levels increased in ST and C (p > 0.05). Total oxidant status (TOS) and oxidative stress index (OSI) reduced ST and C (p < 0.05). Serum interleukin-6 (IL-6) levels did not alter groups ST and C.

CONCLUSION

Strength training did not affect basal serum concentrations of T, GH, IGF-1, COR, IL-6, and TAS, but it caused a decrease in SHBG and IGFBP3 concentrations in ST. Increased basal FT concentration and improved serum TOS may not depend on strength training.

Association of the consumption of common drinks with early puberty in both sexes

Background

We examined the effect of sugar-sweetened beverages (SSB) and common drink intake on pubertal development in both sexes.

Methods

Data were retrieved from Taiwan Children Health Study, which involved detailed pubertal stage assessments of 2,819 schoolchildren aged 11 years in 2011-2012. Drawings of secondary sexual characteristics and self-reported age at menarche or voice breaking were used to assess pubertal stages. Dietary intake was assessed using a detailed semi-quantitative food frequency questionnaire. Generalized estimating equation modeling was applied to obtain odds ratios (ORs) and 95% confidence intervals (CIs) to represent the effects of each drink on early pubertal development outcomes.

Results

In boys, an one cup/day increment of a SSB was associated with earlier voice breaking (β = -0.12; 95% CI = -0.20, -0.04), whereas consuming yogurt (≥2 cups/day) was a protective factor against early puberty (OR = 0.78; 95% CI = 0.73, 0.83). In girls, SSB consumption was associated with increased risk of early puberty in a dose-response manner, and a similar protective effect of yogurt consumption and fermented probiotic drink (≥2 cups/day) against early puberty was observed (OR = 0.96; 95% CI = 0.94, 0.99). Furthermore, the intake of both total sugar and added sugar within SSBs increased risk of early puberty in girls but not in boys.

Conclusions

Sugar-sweetened beverages were associated with early puberty, and probiotic drinks appeared to mitigate this link. These findings indicate that the gut-brain axis could play a crucial role in sexual maturation.