Dual energy X-ray absorptiometry positioning protocols in assessing body composition: A systematic review of the literature

Assessment of Adiposity in Patients with Psoriasis and its Correlation with Disease Severity: A Case-Control Study

Background

Psoriasis and obesity are known to share many mediators of inflammation with each other such as TNF-α and IL-6. Obesity, being a low-grade inflammatory state, is known to affect the disease course, severity, predisposition, and response to therapy in psoriatic patients. Whole-body dual-energy X-ray absorptiometry (DEXA) is a proven method to estimate total, abdominal, and extremity fat mass.

Objectives

The present study aimed to assess the correlation of the severity of psoriasis with adiposity using regional fat mass DEXA indices.

Patients and Methods

This was a case-control study involving 153 cases followed through till the completion of the study. A total of 153 age and gender-matched controls were included in the study after ruling out confounding factors. DEXA scans were conducted on both cases and controls; the following indices, including total body fat percentage, android-gynoid ratio, and trunk/limb fat mass ratio, were analyzed.

Results

The total fat percentage, as assessed by DEXA scan, had a mean of 29.13 ± 9.66 (32.12 ± 9.51 for cases and 26.13 ± 8.87 for controls) with a significant P value of <0.001. The android/gynoid ratio had a mean of 1.01 ± 0.22 (1.09 ± 0.21 for cases and 0.93 ± 0.21 for controls). Percentage fat trunk/percentage fat limbs (central/peripheral fat) had a mean of 1.05 ± 0.16 (1.08 ± 0.15 for cases and 1.03 ± 0.16 for controls) with a significant P value of <0.001. The correlation of DEXA adiposity grading with the severity of psoriasis was found to be significant, with a P value of <0.001.

Limitations

The cross-sectional design restricts assessment to associations rather than causality. Although major confounding factors were ruled out during recruitment, variables such as lifestyle and dietary habits, physical activity levels, and treatment history were not the primary focus and hence not extensively analyzed. The sample size analyses, such as stratification by gender or treatment modalities, may benefit from larger cohorts in future research.

Conclusion

DEXA is a useful indicator of adiposity, with greater total fat percentage, android/gynoid ratio, and trunk/limb fat mass ratio in cases compared to controls and it was positively correlated with the severity of psoriasis in our study.

The Effect of Creatine Supplementation on Lean Body Mass with and Without Resistance Training

Background/Objectives: Creatine monohydrate (CrM) is considered to be one of the most effective supplements for enhancing lean body mass during resistance training. However, CrM may influence body water content, potentially confounding lean body mass measurements. Therefore, this randomised controlled trial assessed the effect of CrM alone on lean body mass following a supplement wash-in, and when combined with a resistance training program. Methods: Sixty-three (34 females, 29 males, 31 ± 8 years) participants were randomised to supplement with CrM (5 g/day for 13 weeks: wash-in + 12-week resistance training) or serve as a control (received no creatine or placebo). Lean body mass was measured using dual X-ray absorptiometry at baseline, post 7-day wash-in, and post 12 weeks of resistance training. Both groups began the same training program post CrM wash-in. Results: After the 7-day wash-in, the supplement group gained 0.51 ± 1.79 kg more lean body mass than the control group (p = 0.03). Following the wash-in, both groups gained 2 kg after resistance training (p < 0.0001), with no between-group difference in lean body mass growth (p = 0.71). Sex-disaggregated analysis showed that the supplement group, only in females, gained 0.59 ± 1.61 kg more lean body mass than the controls (p = 0.04). There were no group differences in lean body mass growth following resistance training in females (p = 0.10) or males (p = 0.35). Conclusions: A 7-day CrM wash-in increased lean body mass, particularly in females. Thereafter, CrM did not enhance lean body mass growth when combined with resistance training, likely due to its short-term effects on lean body mass measurements. A maintenance dose of higher than 5 g/day may be necessary to augment lean body mass growth.

The Effect of Creatine Supplementation on Resistance Training-Based Changes to Body Composition: A Systematic Review and Meta-analysis

ABSTRACT

Desai, I, Wewege, MA, Jones, MD, Clifford, BK, Pandit, A, Kaakoush, NO, Simar, D, and Hagstrom, AD. The effect of creatine supplementation on resistance training-based changes to body composition: A systematic review and meta-analysis. J Strength Cond Res 38(10): 1813-1821, 2024-The purpose of this review was to determine the added effect of creatine supplementation on changes in body composition with resistance training in adults younger than 50 years. The review protocol was preregistered on the Open Science Framework (osf.io/x48a6/). Our primary outcome was lean body mass (LBM); secondary outcomes were body fat percentage (%) and body fat mass (kg). We performed a random-effects meta-analysis in R using the metafor package. Subgroup analyses were conducted to examine the effects of training status and use of a carbohydrate drink with creatine. We conducted a meta-regression to examine the moderating effect of total training volume. Statistical significance was set at p < 0.05. One thousand six hundred ninety-four records were screened, and 67 full-text articles were assessed for eligibility. Twelve studies were included in the meta-analysis. Fifty-two percentages of the studies had low risk, 41% some concerns, and 7% high risk of bias. Compared with resistance training (RT) alone, creatine supplementation increased LBM by 1.14 kg (95% CI 0.69 to 1.59), and reduced body fat percentage by -0.88% (95% CI -1.66 to -0.11) and body fat mass by -0.73 kg (95% CI -1.34 to -0.11). There were no differences between training status or carbohydrate subgroups. Training volume was not associated with effect size in all outcomes; 7 g or 0.3 g/kg of body mass of creatine per day is likely to increase LBM by 1 kg and reduce fat mass by 0.7 kg more than RT alone. Concurrent carbohydrate ingestion did not enhance the hypertrophy benefits of creatine.

A critical review of the feasibility of emerging technologies for improving safety behavior on construction sites

INTRODUCTION

Advancements in the modern construction industry have contributed to the development of a range of technology-based interventions to improve the safety behavior of front-line construction workers. Notwithstanding the extensive research on safety behavior, there is still a paucity of research on assessing technology interventions of safety behavior to provide an overview of their strengths and limitations. The present study aims to bridge this gap in the literature and identify the main trends of research.

METHOD

A systematic review and critical content analysis are adopted to capture an overview of the state of knowledge on safety behavior technologies. As a result of searching Scopus, Web of Science, and Google Scholar databases in the period from Jan 2010 to Feb 2023, a total of 359 potential studies went through the systematic screening process and finally, 48 representative studies were selected followed by an assessment of the feasibility and applicability of the safety behavior technologies.

RESULTS

It was found that safety behavior technology is characterized by seven technologies including virtual-reality simulation (T1), eye-tracking technology (T2), prediction modeling of safety behavior (T3), computer-based training (T4), drone/sensor-based hazard monitoring (T5), vision-based behavior monitoring (T6), and real-time positioning (T7).

CONCLUSIONS

This research improves understanding of the status of safety behavior technologies and provides a critical review of their feasibility from the perspective of four assessment criteria including application, limitation, benefit, and feasibility.

PRACTICAL APPLICATIONS

The categorizations of technologies add value to the body of knowledge in terms of generic requirements for their implementation and adaptation on construction sites.

Body Composition and Its Interaction with Bone Mineral Density and Biochemical and Nutritional Parameters in Chilean Adults with Overweight/Obesity and Normal Weight

This study aimed to compare and relate the body composition (obtained through anthropometry with the pentacompartmental model and the tricompartmental model by DXA) with bone mineral density and biochemical and nutritional parameters in Chilean adults with overweight/obesity and normal weight from La Araucanía region, Chile. A case-control study was conducted with 116 adults and volunteers from the PURE cohort, collecting sociodemographic data, BMI assessment, waist-to-hip ratio (WHR), and body composition using the pentacompartmental model (5CM) and tricompartmental model (3CM) by DXA, as well as bone mineral density (BMD). Blood biochemical parameters (fasting glucose and lipid profile), physical activity (PA) measured by GPAQ, and average dietary habits (R24h) were measured. In the overweight/obesity group, the 5CM and 3CM adipose mass were indirectly and moderately correlated with PA (p < 0.05), except in the male 5CM group. In the overweight/obesity group, muscle and fat-free mass (FFM) of the 5CM and 3CM correlated directly and moderately with blood fasting glucose (BFG) and BMD (p < 0.05), except in females, where FFM was not related to BMD but was related to residual mass (p < 0.01). Independent of gender and BMI, bone mineral content was positively and highly correlated with BMD (p < 0.0000). In the male overweight/obesity group, bone, skin, and residual mass were correlated with BFG (p < 0.05). In conclusion, for the assessment of non-athletic adult populations, more routine use of the 5CM in clinical practice is recommended.

The Correlation of Total Percent Fat With Alterations in Cholesterol and Triglycerides in Adults

Background

To evaluate the detailed relationship between total percent fat (TPF) and cardiovascular disease (CVD)-related lipid biomarkers among adults and find a non-invasive indicator for screening and monitoring of the high CVD risk population.

Methods

Data of 13,160 adults were obtained from the National Health and Examination Survey (NHANES) from 1999 to 2018. TPF was assessed by dual-energy x-ray absorptiometry (DXA), and CVD-related lipid biomarkers included total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). Multivariable linear regression models were used to examine associations between TPF with four kinds of lipid biomarkers, and smooth curve fittings and generalized additive models were used to address the non-linear relationship between them. The inflection points were calculated by the recursive algorithm when non-linearities were detected and then weighted two-piecewise linear regression models were constructed.

Results

In multivariable regression, increasing TPF was positively associated with TC, TG, and LDL-C and negatively with HDL-C (all p < 0.001). In addition, the non-linear relationships between them were also identified by generalized additive models and smooth curve fittings. When further stratified TPF by sex, the fitted smooth curves were nearly inverted U-shaped and U-shaped curves, the inflection points were calculated, and the weighted two-piecewise linear regression models were constructed, respectively. The same results existed between android percent fat and these four lipid biomarkers.

Conclusions

Total percent fat was significantly associated with CVD-related lipid biomarkers in adults, positively with TC, TG, and LDL-C and negatively with HDL-C. It could be used as a non-invasive screener and monitor of high CVD risk population when their TPF values were less than the inflection points.

The Correlation of Prediabetes and Type 2 Diabetes With Adiposity in Adults

Background

Fat metabolism is associated with prediabetes and type 2 diabetes mellitus (T2DM). The aim of this study was to evaluate the detailed correlation of diabetes status with adiposity among adults.

Methods

Briefly, 28,429 adults aged ≥18 years from both sexes in the National Health and Nutrition Examination Survey (NHANES) 1999–2018 were included in this study. Multivariable linear regression models were used to examine associations of prediabetes and diabetes status, disease duration of T2DM, serum glucose, glycohemoglobin (HbA1c) with total percent fat (TPF), and fat mass distribution.

Results

After adjusting for sociodemographic covariates, health behaviors, hypertension, hypercholesterolemia, there were direct associations of prediabetes and T2DM status with TPF, trunk fat mass, android fat mass, gynoid fat mass and android to gynoid ratio compared with non-diabetes. But the fat mass decreased with the increase of the disease duration in patients with T2DM. Besides, when stratifying by diabetes status, we found direct associations of serum glucose and HbA1c with TPF, trunk fat mass, android fat mass, gynoid fat mass, and android to gynoid ratio in non-diabetic and prediabetic participants. But in patients with T2DM, inverse associations of serum glucose and HbA1c with fat mass were observed.

Conclusions

This study indicated that adults with prediabetes and T2DM had significantly higher TPF, trunk fat mass, android fat mass, gynoid fat mass, and android to gynoid ratio compared with those without diabetes. Moreover, fat mass decreased as the disease duration increased in patients with T2DM. The associations of serum glucose and HbA1c with TPF and fat mass distribution in patients with T2DM were opposite to the relationships observed in non-diabetic and prediabetic participants.

Effects of supervised high-intensity hardstyle kettlebell training on grip strength and health-related physical fitness in insufficiently active older adults: the BELL pragmatic controlled trial

The Ballistic Exercise of the Lower Limb (BELL) trial examined the efficacy and safety of a pragmatic hardstyle kettlebell training program in older adults. Insufficiently active men and women aged 59–79 years, were recruited to a 6-month repeated measures study, involving 3-months usual activity and 3-months progressive hardstyle kettlebell training. Health-related physical fitness outcomes included: grip strength [GS], 6-min walk distance [6MWD], resting heart rate [HR], stair-climb [SC], leg extensor strength [LES], hip extensor strength [HES], Sit-To-Stand [STS], vertical jump [CMVJ], five-times floor transfer [5xFT], 1RM deadlift, body composition (DXA), attendance, and adverse events. Sixteen males (68.8 ± 4.6 yrs, 176.2 ± 7.8 cm, 90.7 ± 11.0 kg, 29.2 ± 2.6 kg/m²) and sixteen females (68.6 ± 4.7 yrs, 163.9 ± 5.4 cm, 70.4 ± 12.7 kg, 26.3 ± 4.9 kg/m²) were recruited. Compliance with the supervised exercise program was very high (91.5%). Kettlebell training increased GS (R: MD = 7.1 kg 95% CI [4.9, 9.3], L: MD = 6.3 kg 95% CI [4.1, 8.4]), 6MWD (41.7 m, 95% CI [17.9, 65.5]), 1RM (16.2 kg, 95% CI [2.4, 30.0]), 30 s STS (3.3 reps, 95% CI [0.9, 5.7]), LES (R: MD = 61.6 N, 95% CI [4.4, 118.8]), HES (L: MD = 21.0 N,95% CI [4.2,37.8]), appendicular skeletal lean mass (MD = 0.65 kg, 95% CI [0.08, 1.22]), self-reported health change (17.1%, 95% CI [4.4, 29.8]) and decreased SC time (2.7 s, 95% CI [0.2, 5.2]), 5xFT time (6.0 s, 95% CI [2.2, 9.8]) and resting HR (7.4 bpm, 95% CI [0.7, 14.1]). There were four non-serious adverse events. Mean individual training load for group training sessions during the trial was 100,977 ± 9,050 kg. High-intensity hardstyle kettlebell training was well tolerated and improved grip strength and measures of health-related physical fitness in insufficiently active older adults.

Trial registration: Prospectively registered: 20/08/2019, Australian New Zealand Clinical Trials Registry (ACTRN12619001177145).

Physical fitness profiles of female Australian football players across five competition levels

OBJECTIVES

To examine physical fitness profiles of female Australian football players and investigate differences according to competition level.

METHODS

A testing battery of 28 physical fitness assessments was undertaken with 240 players across five competition levels: elite senior (≥18 years), non-elite senior (≥18 years), high-level junior (<18 years), non-elite junior (14-17 years), and non-elite junior (10-13 years). Physical fitness profiles were examined and competition level differences were investigated using multivariate analyses of variance.

RESULTS

Significant differences (p<0.001) were observed between competition levels in body composition (η²_p=0.225), flexibility (η²_p=0.071), muscular strength and endurance (η²_p=0.238), balance (η²_p=0.093), reaction time (η²_p=0.103), and whole-body locomotor performance (η²_p=0.200). Elite seniors and high-level juniors were stronger (p<0.001-0.043), faster (p=0.001-0.022), more responsive (p<0.001-0.048), and had better cardiorespiratory fitness (p<0.001) compared to the non-elite groups. Additionally, body composition and muscular strength and endurance differences were common between the senior and non-elite junior groups.

CONCLUSIONS

This is the first study to comprehensively profile physical characteristics of female Australian footballers across a broader development pathway. These preliminary findings may assist sport practitioners to better understand athlete development, provide insight on talent identification and development programs, and injury management in this population.

Reliability and validity of smartphone applications to measure the spinal range of motion: A systematic review

Introduction: The objective of this study is to conduct a systematic review on the reliability and validity of various smartphone applications for spinal range of motion (ROM) measurements.Methods: Eleven studies were selected following an electronic search of PubMed, CINAHAL, Medline, Embase and SPORTDiscus. Quality appraisals of selected studies were conducted using a standardized appraisal tool.Results: Most studies demonstrated a good intra- and inter-rater reliability, as well as validity in more than 50% of joint movements. At the same time, relative reliability/validity outcomes (e.g. interclass correlation co-efficient) were stronger than absolute reliability/validity outcomes (e.g. mean differences, limits of agreement). Spinal rotation movement showed less reliability and validity when compared to other spinal movements.ConclusionsːResult of the study supports the use of smartphone applications for ROM measurements of spinal joints. However, we cannot advocate the most appropriate application for spinal ROM measurement or suggest which application is superior to all others. As clinicians have multiple options in selecting applications, it is recommended they use applications that have proven reliable and valid for that particular joint. Data from this study provides clinicians with evidence-based research on smartphone devices for measuring spinal joint ROM in clinical settings.

Assessment of body composition in spinal cord injury: A scoping review

The objective of this scoping review was to map the evidence on measurement properties of body composition tools to assess whole-body and regional fat and fat-free mass in adults with SCI, and to identify research gaps in order to set future research priorities. Electronic databases of PubMed, EMBASE and the Cochrane library were searched up to April 2020. Included studies employed assessments related to whole-body or regional fat and/or fat-free mass and provided data to quantify measurement properties that involved adults with SCI. All searches and data extractions were conducted by two independent reviewers. The scoping review was designed and conducted together with an expert panel (n = 8) that represented research, clinical, nutritional and lived SCI experience. The panel collaboratively determined the scope and design of the review and interpreted its findings. Additionally, the expert panel reached out to their professional networks to gain further stakeholder feedback via interactive practitioner surveys and workshops with people with SCI. The research gaps identified by the review, together with discussions among the expert panel including consideration of the survey and workshop feedback, informed the formulation of future research priorities. A total of 42 eligible articles were identified (1,011 males and 143 females). The only tool supported by studies showing both acceptable test-retest reliability and convergent validity was whole-body dual-energy x-ray absorptiometry (DXA). The survey/workshop participants considered the measurement burden of DXA acceptable as long as it was reliable, valid and would do no harm (e.g. radiation, skin damage). Practitioners considered cost and accessibility of DXA major barriers in applied settings. The survey/workshop participants expressed a preference towards simple tools if they could be confident in their reliability and validity. This review suggests that future research should prioritize reliability and validity studies on: (1) DXA as a surrogate 'gold standard' tool to assess whole-body composition, regional fat and fat-free mass; and (2) skinfold thickness and waist circumference as practical low-cost tools to assess regional fat mass in persons with SCI, and (3) females to explore potential sex differences of body composition assessment tools. Registration review protocol: CRD42018090187 (PROSPERO).

Explaining Discrepancies Between Total and Segmental DXA and BIA Body Composition Estimates Using Bayesian Regression

INTRODUCTION/BACKGROUND

Few investigations have sought to explain discrepancies between dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA) body composition estimates. The purpose of this analysis was to explore physiological and anthropometric predictors of discrepancies between DXA and BIA total and segmental body composition estimates.

METHODOLOGY

Assessments via DXA (GE Lunar Prodigy) and single-frequency BIA (RJL Systems Quantum V) were performed in 179 adults (103 F, 76 M, age: 33.6 ± 15.3 yr; BMI: 24.9 ± 4.3 kg/m²). Potential predictor variables for differences between DXA and BIA total and segmental fat mass (FM) and lean soft tissue (LST) estimates were obtained from demographics and laboratory techniques, including DXA, BIA, bioimpedance spectroscopy, air displacement plethysmography, and 3-dimensional optical scanning. To determine meaningful predictors, Bayesian robust regression models were fit using a t-distribution and regularized hierarchical shrinkage "horseshoe" prior. Standardized model coefficients (β) were generated, and leave-one-out cross validation was used to assess model predictive performance.

RESULTS

LST hydration (i.e., total body water:LST) was a predictor of discrepancies in all FM and LST variables (|β|: 0.20-0.82). Additionally, extracellular fluid percentage was a predictor for nearly all outcomes (|β|: 0.19-0.40). Height influenced the agreement between whole-body estimates (|β|: 0.74-0.77), while the mass, length, and composition of body segments were predictors for segmental LST estimates (|β|: 0.23-3.04). Predictors of segmental FM errors were less consistent. Select sex-, race-, or age-based differences between methods were observed. The accuracy of whole-body models was superior to segmental models (leave-one-out cross-validation-adjusted R² of 0.83-0.85 for FM_TOTAL and LST_TOTAL vs. 0.20-0.76 for segmental estimates). For segmental models, predictive performance decreased in the order of: appendicular lean soft tissue, LST_LEGS, LST_TRUNK and FM_LEGS, FM_ARMS, FM_TRUNK, and LST_ARMS.

CONCLUSIONS

These findings indicate the importance of LST hydration, extracellular fluid content, and height for explaining discrepancies between DXA and BIA body composition estimates. These general findings and quantitative interpretation based on the presented data allow for a better understanding of sources of error between 2 popular segmental body composition techniques and facilitate interpretation of estimates from these technologies.

Fat-free mass characteristics vary based on sex, race, and weight status in US adults

Common body composition estimation techniques necessitate assumptions of uniform fat-free mass (FFM) characteristics, although variation due to sex, race, and body characteristics may occur. National Health and Nutrition Examination Survey data from 1999 to 2004, during which paired dual-energy x-ray absorptiometry (DXA) and bioimpedance spectroscopy assessments were performed, were used to estimate FFM characteristics in a sample of 4619 US adults. Calculated FFM characteristics included the density and water, bone mineral, and residual content of FFM. A rapid 4-component model was also produced using DXA and bioimpedance spectroscopy data. Study variables were compared across sex, race/ethnicity, body mass index (BMI), and age categories using multiple pairwise comparisons. A general linear model was used to estimate body composition after controlling for other variables. Statistical analyses accounted for 6-year sampling weights and complex sampling design of the National Health and Nutrition Examination Survey and were based on 5 multiply imputed datasets. Differences in FFM characteristics across sex, race, and BMI were observed, with notable dissimilarities between men and women for all outcome variables. In racial/ethnic comparisons, non-Hispanic blacks most commonly presented distinct FFM characteristics relative to other groups, including greater FFM density and proportion of bone mineral. Body composition errors between DXA and the 4-component model were significantly influenced by sex, age, race, and BMI. In conclusion, FFM characteristics, which are often assumed in body composition estimation methods, vary due to sex, race/ethnicity, and weight status. The variation of FFM characteristics in diverse populations should be considered when body composition is evaluated.

Non-Destructive Imaging and Spectroscopic Techniques for Assessment of Carcass and Meat Quality in Sheep and Goats: A Review

In the last decade, there has been a significant development in rapid, non-destructive and non-invasive techniques to evaluate carcass composition and meat quality of meat species. This article aims to review the recent technological advances of non-destructive and non-invasive techniques to provide objective data to evaluate carcass composition and quality traits of sheep and goat meat. We highlight imaging and spectroscopy techniques and practical aspects, such as accuracy, reliability, cost, portability, speed and ease of use. For the imaging techniques, recent improvements in the use of dual-energy X-ray absorptiometry, computed tomography and magnetic resonance imaging to assess sheep and goat carcass and meat quality will be addressed. Optical technologies are gaining importance for monitoring and evaluating the quality and safety of carcasses and meat and, among them, those that deserve more attention are visible and infrared reflectance spectroscopy, hyperspectral imagery and Raman spectroscopy. In this work, advances in research involving these techniques in their application to sheep and goats are presented and discussed. In recent years, there has been substantial investment and research in fast, non-destructive and easy-to-use technology to raise the standards of quality and food safety in all stages of sheep and goat meat production.

Strength training as a supplemental therapy for androgen deficiency of the aging male (ADAM): study protocol for a three-arm clinical trial

INTRODUCTION

Androgen deficiency of the ageing male is a clinical syndrome resulting from the low production of androgens (testosterone levels <6.9 nmol/L) with symptoms including decline in lean mass, muscle strength, increases in body mass and overall fat mass. The aim of the study is to examine the effect of a 12 week strength training intervention on body composition, physical function, muscle cellular and molecular and selected biochemical markers of metabolic health in hypogonadal patients.

METHODS AND ANALYSIS

The study is three-group controlled 12-week experiment to assess the effect of strength training on hypogonadal patients with testosterone replacement therapy and newly diagnosed males without testosterone replacement therapy. Age matched healthy eugonadal males are also engaged in strength training. Lean mass is used to determine sample size indicating, that 22 subjects per group will be sufficient to detect intervention related changes at the power of 0.90. All outcomes are collected before the intervention (pre-intervention assessments) and after the intervention (post-intervention assessments). Clinical outcomes are body composition (lean mass, fat mass and total body mass) measured by dual-energy X-ray absorptiometry, physical functioning assessed by physical tests and psychosocial functioning. The most important haematological and biochemical parameters included are glucose, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, testosterone, luteinizing hormone, follicle-stimulating hormone, sexhormone-binding globulin, insulin and prostate-specific antigen. Muscle cellular and molecular outcomes are muscle fibre size and regulators of muscle fibre size. Muscle cellular outcomes are measured from muscle biopsies obtained from musculus vastus lateralis.

ETHICS AND DISSEMINATION

This trial is approved by Ethics Committee of the University Hospital in Bratislava, Slovakia, (ref. trial number: 127/2017) and all subjects will be fully informed on the rationale, risks and benefits of the study and sign the written informed consent prior to entering the study. Results will be published in peer-reviewed journals and presented in scientific conferences.

TRIAL REGISTRATION NUMBER

NCT03282682.

Relationship between DXA measured metrics of adiposity and glucose homeostasis; An analysis of the NHANES data

Introduction

Obesity is associated with insulin resistance and type 2 diabetes. Dual-energy X-ray absorptiometry (DXA) is a means of determining body composition and body fat distribution at different sites including whole body and trunk–locations where there tends to be high correlation at an individual level.

Methods

We performed an analysis of DXA-derived metrics of adiposity (truncal fat %,subtotal fat % and total fat %) from the NHANES database and then correlated the findings with markers of insulin resistance. We analyzed the data from DXA scans in NHANES 1999–2004. Homeostatic model assessment-insulin resistance and HOMA-β (beta-cell function) were estimated. Spearman correlation coefficients were calculated (ρ) between HOMA-IR,HOMA-β and different measures of obesity (Waist circumference(in cm), Body Mass Index (kg/m2), truncal fat %, subtotal fat % as well as total fat %) to gauge the relationship between markers of glucose homeostasis and DXA derived metrics of obesity. We also performed logarithmic transformation of HOMA-IR as well as HOMA-β to ensure normality of distribution and to meet the criteria for regression analysis. A forward selection model (by outcome and gender) was performed to predict log transformed insulin resistance (log HOMA-IR) as well as log transformed HOMA-β (log HOMA-β,measure of beta cell function) from age, serum triglycerides, HDL, trunk fat % and the SBP (in both males and females separately), after reviewing the spearman correlation coefficients.

Results

There were a total of 6147 men and 6369 women who were part of the study cohort. There was a positive correlation between markers of adiposity and log HOMA-IR and log HOMA-β in both males and females.Truncal fat % had the highest nonparametric correlation coefficent with log HOMA-IR among the DXA derived fat% (0.54 in males and 048 in females). In the multivariate analysis, truncal fat % was an independent predictor of logHOMA-IR as well as logHOMA-β. In males, the significant predictors of log HOMA-IR were; age, truncal fat % and HDL cholesterol (Adjusted R square of 0.325 (±0.66), F(3,207) = 34.63, p < .01). In females, the significant predictors of log HOMA-IR were; age, truncal fat %, SBP, Serum triglyceride and HDL cholesterol (Adjusted R square of 0.307 (±0.65),F(5,198) = 18.9, p < .01). In both males and females, the significant predictors of log HOMA-β were; age, and truncal fat % (Males; adjusted R square of 0.25 (±0.63), F (2,208) = 36.4, p < .01, Females; adjusted R square of 0.27 (±0.62), F (2,201) = 38.4, p < .01).

Conclusions

Body fat % on DXA is an imaging biomarker for insulin resistance. Incorporating this important information into DXA acquisitions and reporting frameworks may allow for this information to be available to providers who refer patients for these imaging studies.

Reliability and validity of clinically accessible smartphone applications to measure joint range of motion: A systematic review

Measuring joint range of motion is an important skill for many allied health professionals. While the Universal Goniometer is the most commonly utilised clinical tool for measuring joint range of motion, the evolution of smartphone technology and applications (apps) provides the clinician with more measurement options. However, the reliability and validity of these smartphones and apps is still somewhat uncertain. The aim of this study was to systematically review the literature regarding the intra- and inter-rater reliability and validity of smartphones and apps to measure joint range of motion. Eligible studies were published in English peer-reviewed journals with full text available, involving the assessment of reliability and/or validity of a non-videographic smartphone app to measure joint range of motion in participants >18 years old. An electronic search using PubMed, Medline via Ovid, EMBASE, CINAHL, and SPORTSDiscus was performed. The risk of bias was assessed using a standardised appraisal tool. Twenty-three of the eligible 25 studies exceeded the minimum 60% score to be classified as a low risk of bias, although 3 of the 13 criteria were not achieved in >50% of the studies. Most of the studies demonstrated adequate intra-rater or inter-rater reliability and/or validity for >50% of the range of motion tests across all joints assessed. However, this level of evidence appeared weaker for absolute (e.g. mean difference ± limit of agreement, minimal detectable change) than relative (e.g. intraclass correlation, correlation) measures; and for spinal rotation than spinal extension, flexion and lateral flexion. Our results provide clinicians with sufficient evidence to support the use of smartphones and apps in place of goniometers to measure joint motion. Future research should address some methodological limitations of the literature, especially including the inclusion of absolute and not just relative reliability and validity statistics.

Metabolic Syndrome and Its Associations with Components of Sarcopenia in Overweight and Obese Older Adults

Ageing, obesity and the metabolic syndrome (MetS) may all contribute to poor muscle health (sarcopenia). This study aimed to determine the cross-sectional associations between MetS (International Diabetes Federation classification) and sarcopenia (revised European Working Group on Sarcopenia in Older People definition) in 84 overweight and obese older adults. Components of sarcopenia included muscle strength (hand grip and leg extension), physical performance (stair climb test and short physical performance battery (SPPB), including gait speed and repeated chair stands time), muscle mass (appendicular lean mass (ALM), dual-energy X-ray absorptiometry), muscle size (peripheral quantitative computed tomography-determined calf and forearm cross-sectional area (CSA)) and muscle quality (muscle density and strength normalised to lean mass). Waist circumference was associated with greater muscle size, but poorer leg extension strength, chair stands and stair climb time, gait speed, SPPB scores and muscle quality measures (all p < 0.05). MetS was positively associated with ALM and forearm muscle CSA, and negatively associated with muscle quality measures and chair stands time (all p < 0.05). MetS is associated with larger muscle size, yet poorer muscle quality in overweight and obese older adults. Assessments of muscle function and quality should be considered for obese older adults and those with MetS.

Body composition and sarcopenia: The next-generation of personalized oncology and pharmacology?

Body composition has gained increasing attention in oncology in recent years due to fact that sarcopenia has been revealed to be a strong prognostic indicator for survival across multiple stages and cancer types and a predictive factor for toxicity and surgery complications. Accumulating evidence over the last decade has unraveled the "pharmacology" of sarcopenia. Lean body mass may be more relevant to define drug dosing than the "classical" body surface area or flat-fixed dosing in patients with cancer. Since sarcopenia has a major impact on patient survival and quality of life, therapeutic interventions aiming at reducing muscle loss have been developed and are being prospectively evaluated in randomized controlled trials. It is now acknowledged that this supportive care dimension of oncological management is essential to ensure the success of any anticancer treatment. The field of sarcopenia and body composition in cancer is developing quickly, with (i) the newly identified concept of sarcopenic obesity defined as a specific pathophysiological entity, (ii) unsolved issues regarding the best evaluation modalities and cut-off for definition of sarcopenia on imaging, (iii) first results from clinical trials evaluating physical activity, and (iv) emerging body-composition-tailored drug administration schemes. In this context, we propose a comprehensive review providing a panoramic approach of the clinical, pharmacological and therapeutic implications of sarcopenia and body composition in oncology.