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Males typically outperform females in Olympic-style weightlifting, as judged by total weight lifted, and similarly heavier athletes outperform lighter athletes. Current methods can standardise weightlifting performances across body mass to compare different body mass classes, but they do not address the sex gap. This study introduces a novel approach that puts male and female performances on a single unified scale, across the range of body mass, allowing mixed sex teams to be compared. The method uses standardised residuals or "z-scores" derived from models of performance regressed on sex and body mass fitted by GAMLSS (generalised additive models for location, scale and shape). Reference data come from the International Weightlifting Federation (IWF) world championships and Olympics 2017–2023. To ensure the validity of the model for ranking team performances in the future, results from 2000 to 2023 were compared and shown to be stable over time. A web application is available to aid athletes, coaches and health professionals to compare performances and monitor progress over time. [ABSTRACT FROM AUTHOR]

Background Until recently, pediatric body composition reference data were very limited, hindering interpretation of measurements. In the last decade, such data emerged for several techniques for children [greater than or equal to] 5 years, but equivalent data for younger age groups remain lacking, due to their poor compliance with most techniques. Objectives To provide reference data for use in clinical practice and research from 6 weeks to 5 years, that are based on measurements of total body water (TBW) by isotope dilution. Design The data on anthropometry and TBW were available from studies of 463 infants and children aged 6 weeks to 7 years, conducted between 1988 and 2010. Both breast-fed and formula-fed infants were included. TBW was measured by .sup.2H- or .sup.18O-labeled water, and converted to fat-free mass (FFM) using published hydration coefficients. Reference charts and SD scores (SDS) were constructed for FFM, fat mass (FM), FFM index and FM index for each sex, using the lambda-mu-sigma method. Results Both sexes were significantly heavier and longer than UK 1990 reference data (p < 0.01), but did not differ in body mass index SDS. Breast-fed infants were longer than formula-fed infants but did not differ in body composition. Conclusions These reference data will enhance the ability of clinicians to assess and monitor body composition and FFM/FM accretion in clinical practice in younger age groups. Total body water can be measured in most patients, though abnormalities of hydration must be addressed. However, the centiles do not overlap exactly with those published for older age groups, limiting comparability between younger and older children., Author(s): Jonathan C. K. Wells [sup.1] [sup.2] , Peter S. W. Davies [sup.3] , Mary S. Fewtrell [sup.1] [sup.2] , Tim J. Cole [sup.2] Author Affiliations: (1) Childhood Nutrition Research [...]

Hypochondroplasia (HCH) is a rare skeletal dysplasia causing mild short stature. There is a paucity of growth reference charts for this population. Anthropometric data were collected to generate height, weight, and head circumference (HC) growth reference charts for children with a diagnosis of HCH. Mixed longitudinal anthropometric data and genetic analysis results were collected from 14 European specialized skeletal dysplasia centers. Growth charts were generated using Generalized Additive Models for Location, Scale, and Shape. Measurements for height (983), weight (896), and HC (389) were collected from 188 (79 female) children with a diagnosis of HCH aged 0–18 years. Of the 84 children who underwent genetic testing, a pathogenic variant in FGFR3 was identified in 92% (77). The data were used to generate growth references for height, weight, and HC, plotted as charts with seven centiles from 2nd to 98th, for ages 0–4 and 0–16 years. HCH‐specific growth charts are important in the clinical care of these children. They help to identify if other comorbidities are present that affect growth and development and serve as an important benchmark for any prospective interventional research studies and trials. [ABSTRACT FROM AUTHOR]

Background Individuals with obesity do not represent a homogeneous group in terms of cardiometabolic risk. Using 3 nationally representative British birth cohorts, we investigated whether the duration of obesity was related to heterogeneity in cardiometabolic risk. Methods and findings We used harmonised body mass index (BMI) and cardiometabolic disease risk factor data from 20,746 participants (49.1% male and 97.2% white British) enrolled in 3 British birth cohort studies: the 1946 National Survey of Health and Development (NSHD), the 1958 National Child Development Study (NCDS), and the 1970 British Cohort Study (BCS70). Within each cohort, individual life course BMI trajectories were created between 10 and 40 years of age, and from these, age of obesity onset, duration spent obese (range 0 to 30 years), and cumulative obesity severity were derived. Obesity duration was examined in relation to a number of cardiometabolic disease risk factors collected in mid-adulthood: systolic (SBP) and diastolic blood pressure (DBP), high-density-lipoprotein cholesterol (HDL-C), and glycated haemoglobin (HbA1c). A greater obesity duration was associated with worse values for all cardiometabolic disease risk factors. The strongest association with obesity duration was for HbA1c: HbA1c levels in those with obesity for Conclusions Given that the obesity epidemic is characterised by a much earlier onset of obesity and consequently a greater lifetime exposure, our findings suggest that health policy recommendations aimed at preventing early obesity onset, and therefore reducing lifetime exposure, may help reduce the risk of diabetes, independently of obesity severity. However, to test the robustness of our observed associations, triangulation of evidence from different epidemiological approaches (e.g., mendelian randomization and negative control studies) should be obtained., Author(s): Tom Norris 1,*, Tim J. Cole 2, David Bann 3, Mark Hamer 4, Rebecca Hardy 5, Leah Li 2, Ken K. Ong 6, George B. Ploubidis 3, Russell Viner [...]

Bland-Altman plots can be useful in paired data settings such as measurement-method comparison studies. A Bland-Altman plot has differences, percentage differences, or ratios on the y axis and a mean of the data pairs on the x axis, with 95% limits of agreement indicating the central 95% range of differences, percentage differences, or ratios. This range can vary with the mean. We introduce the community-contributed blandaltman command, which uniquely in Stata can 1) create Bland-Altman plots featuring ratios in addition to differences and percentage differences, 2) allow the limits of agreement for ratios and percentage differences to vary as a function of the mean, and 3) add confidence intervals, prediction intervals, and tolerance intervals to the plots. [ABSTRACT FROM AUTHOR]

Objective: To explore patterns of post-malnutrition growth (PMGr) during and after treatment for severe malnutrition and describe associations with survival and non-communicable disease (NCD) risk 7 years post-treatment. Design: Six indicators of PMGr were derived based on a variety of timepoints, weight, weight-for-age z-score and height-for-age z-score (HAZ). Three categorisation methods included no categorisation, quintiles and latent class analysis (LCA). Associations with mortality risk and seven NCD indicators were analysed. Setting: Secondary data from Blantyre, Malawi between 2006 and 2014. Participants: A cohort of 1024 children treated for severe malnutrition (weight-for-length z-score < 70 % median and/or MUAC (mid-upper arm circumference) < 110 mm and/or bilateral oedema) at ages 5–168 months. Results: Faster weight gain during treatment (g/d) and after treatment (g/kg/day) was associated with lower risk of death (adjusted OR 0·99, 95 % CI 0·99, 1·00; and adjusted OR 0·91, 95 % CI 0·87, 0·94, respectively). In survivors (mean age 9 years), it was associated with greater hand grip strength (0·02, 95 % CI 0·00, 0·03) and larger HAZ (6·62, 95 % CI 1·31, 11·9), both indicators of better health. However, faster weight gain was also associated with increased waist:hip ratio (0·02, 95 % CI 0·01, 0·03), an indicator of later-life NCD risk. The clearest patterns of association were seen when defining PMGr based on weight gain in g/d during treatment and using the LCA method to describe growth patterns. Weight deficit at admission was a major confounder. Conclusions: A complex pattern of benefits and risks is associated with faster PMGr. Both initial weight deficit and rate of weight gain have important implications for future health. [ABSTRACT FROM AUTHOR]