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Aim: Emerging evidence suggests that pubertal tempo, that is rate of passage through puberty, has relevance to adolescent mood and behaviour. However, its wider health and developmental significance remain unclear. This systematic review sought to clarify the relationship of pubertal tempo to indicators of health and development, and to document tempo definitions and pubertal durations reported in the literature.Methods: Eight electronic databases were searched from earliest record to July 2018. Study eligibility: healthy participants; age 8-21 years; ≥2 longitudinal measures of puberty; analysis of tempo against a health or developmental indicator.Results: Thirty-eight studies met eligibility, and these reported on diverse tempo definitions and seven health- and development-related domains. Data sets with varying tempo definitions converged on an association of rapid pubertal progression to: (a) higher adiposity during childhood and adolescence in both sexes; and (b) lower psychosocial well-being in adolescent males. Later thelarche unanimously predicted faster progression to menarche in females, but this compensation was largely undetected when alternate definitions of pubertal timing and/or tempo were used. Duration of puberty ranged from 2.5-4.1 years.Conclusion: Pubertal tempo may be clinically relevant when considering trajectories of adiposity and psychosocial well-being among adolescents, especially males. Consensus on the definition of tempo would facilitate between-study comparisons. [ABSTRACT FROM AUTHOR]

Iron is an essential micronutrient for human health and inadequate intake may result in iron deficiency (ID) or iron deficiency anaemia (IDA). Unlike other recent studies investigating iron status in young women, this cross-sectional study analysed dietary intake and biochemical data from healthy young (18-35 years) women (n = 299) to determine the association between both haem iron (HI) and non-haem iron (NHI) intakes and serum ferritin (SF). Dietary restraint and possible inflammation secondary to obesity were also measured and accounted for, and energy intake was adjusted for using the residuals method. Independent samples t-tests and chi-squared tests were performed, and factors found to be significantly different between iron replete (IR) and ID/IDA participants were analysed using general linear modelling. ID/IDA participants consumed significantly lower total energy than iron replete (IR) (p = 0.003). Lower energy intake was also associated with higher levels of dietary restraint (p = 0.001). Both HI and NHI were positively associated with SF with HI was found to be a stronger predictor (β = 0.128, p = 0.009) than NHI (β = 0.037, p = 0.028). The study demonstrates that intake of both HI and NHI, as well as adequate dietary energy, are associated with normal iron status levels in young women, and that restrained eaters may be at greater risk of low iron status. [ABSTRACT FROM AUTHOR]

Women of reproductive age are at increased risk for iron deficiency (ID) and iron deficiency anemia (IDA), with both implicated in decreased cognitive function (CF). Obesity may complicate this association via inflammatory-mediated ferritin elevation. This cross-sectional study examined the association between hematological iron status (iron replete (IR), ID or IDA) and CF in healthy, young (18-35 years) women of normal-weight (NW: BMI 18.5-24.9 kg/m²) or obese-weight (OB: BMI >30 kg/m²). Participants completed a validated, computer-based cognition assessment evaluating impulsivity, attention, information processing, memory and executive function; CF reported as z-scores (mean ± SD). Iron status and CF were compared between groups via ANOVA, with adjustment for potential confounders (BMI, physical activity, C-reactive protein) via ANCOVA. A total of 157 NW and 142 OB women (25.8 ± 5.1 years) participated. Prevalence of ID and IDA were 14% and 6% respectively, with no significant difference between NW and OB groups. Women with IDA scored significantly lower on attention (although within normal range; ±1 z-score), compared to ID (IDA: -0.75 ± 1.89; ID: 0.53 ± 1.37; p = 0.004) but not IR (0.03 ± 1.33, p = 0.21) groups; there were no significant differences between ID and IR groups (p = 0.34). Adjustment for confounders did not significantly alter these results. In conclusion, women with IDA showed significantly reduced attention compared to women with ID. [ABSTRACT FROM AUTHOR]

Weight-making practices have been shown to impair musculoskeletal and physiological function of jockeys. This study investigated the “in-race” heart rate (HR) responses and hydration status during competitive racing, as well as selected physiological and lifestyle parameters of professional jockeys based in Hong Kong. “In-race” HR responses and early morning hydration status of 20 male jockeys were examined in hot and moderate climactic occasions. Additionally, bone mineral density (BMD), dietary intake and lifestyle choices were assessed. Osteopenia was observed in the calcanei of jockeys (left: 0.51 ± 0.06; right: 0.46 ± 0.12 g · cm−2). Energy and protein intake were significantly lower on a race day compared to a non-race day (P < 0.05). “In-race” HRmaxvalues were similar to those from VO2maxlaboratory tests (186 ± 14 vs. 185 ± 8 bpm). Hypohydration was observed on both racing days. (USG: 1.0247 ± 0.006 and 1.0256 ± 0.0258 mg · L−1for hot and moderate conditions, respectively). Sauna usage (25.5%) and food restriction (20.4%) were the most common weight-making practices. Current lifestyle choices of jockeys result in suboptimal bone health, hydration status and nutritional intake, which can significantly enhance the fracture risk. Further research should develop exercise and nutrition guidelines for optimising their skeletal health. [ABSTRACT FROM AUTHOR]

Context The study of gonadal hormone effects on adolescent wellbeing has been limited by logistical challenges. Urine hormone profiling offers new opportunities to understand the health and behavioral implications of puberty hormones. Objective To characterize pubertal change in urinary testosterone and estradiol among male and female adolescents, respectively. Design Three-year prospective cohort study. Setting Australian regional community. Participants 282 (163 male) normally developing adolescents aged 11.8 ± 1.0 years at baseline. Main outcome measure Quarterly urine measurements of testosterone and estradiol (mass spectrometry); annual anthropometric assessment and Tanner stage (TS) self-report. Results Two-class sigmoidal and quadratic growth mixture models (centered on age at TS3) were identified as best-fit for describing testosterone (male) and estradiol (female) change. Classes 1 (male: 63%; female: 82%) and 2 (male: 37%; female: 18%) were respectively named the "stable" and "unstable" trajectories, characterized by different standard deviation of quarterly hormone change and magnitude of hormone peaks and troughs (all P < 0.001). Compared with class 1 (stable), class 2 males were taller at baseline (154 vs 151 cm), reported earlier and faster TS progression (P < 0.01), and showed higher serum testosterone levels at baseline and 3 years (P ≤ 0.01). Class 2 females exhibited smaller height and weight gains over the 3 years and had higher baseline serum estradiol (249 vs 98 pmol/L; P = 0.002) than class 1. Conclusions Adolescents showed 2 distinct urinary gonadal hormone trajectories, characterized by stability of change over time, which were not associated with consistent anthropometric differences. Results provide a methodology for studying gonadal hormone impacts on other aspects of biopsychosocial wellbeing. Identification of potential "at-risk" hormone groups would be important for planning supportive interventions. [ABSTRACT FROM AUTHOR]