Skinfold Thickness

BackgroundGiven that it is not feasible to use dual x-ray absorptiometry (DXA) or other reference methods to measure adiposity in all pediatric clinical and research settings, it is important to identify reasonable alternatives. Therefore, we sought to determine the extent to which other adiposity measures were correlated with DXA fat mass in school-aged children.MethodsIn 1110 children aged 6.5-10.9 years in the pre-birth cohort Project Viva, we calculated Spearman correlation coefficients between DXA (n=875) and other adiposity measures including body mass index (BMI), skinfold thickness, circumferences, and bioimpedance. We also computed correlations between lean body mass measures.Results50.0% of the children were female and 36.5% were non-white. Mean (SD) BMI was 17.2 (3.1) and total fat mass by DXA was 7.5 (3.9) kg. DXA total fat mass was highly correlated with BMI (r(s)=0.83), bioimpedance total fat (r(s)=0.87), and sum of skinfolds (r(s)=0.90), and DXA trunk fat was highly correlated with waist circumference (r(s)=0.79). Correlations of BMI with other adiposity indices were high, e.g., with waist circumference (r(s)=0.86) and sum of subscapular plus triceps skinfolds (r(s)=0.79). DXA fat-free mass and bioimpedance fat-free mass were highly correlated (r(s)=0.94).ConclusionsIn school-aged children, BMI, sum of skinfolds, and other adiposity measures were strongly correlated with DXA fat mass. Although these measurement methods have limitations, BMI and skinfolds are adequate surrogate measures of relative adiposity in children when DXA is not practical.

Whilst the assessment of body composition is routine practice in sport, there remains considerable debate on the best tools available, with the chosen technique often based upon convenience rather than understanding the method and its limitations. The aim of this manuscript was threefold: (1) provide an overview of the common methodologies used within sport to measure body composition, specifically hydro-densitometry, air displacement plethysmography, bioelectrical impedance analysis and spectroscopy, ultra-sound, three-dimensional scanning, dual-energy X-ray absorptiometry (DXA) and skinfold thickness; (2) compare the efficacy of what are widely believed to be the most accurate (DXA) and practical (skinfold thickness) assessment tools and (3) provide a framework to help select the most appropriate assessment in applied sports practice including insights from the authors' experiences working in elite sport. Traditionally, skinfold thickness has been the most popular method of body composition but the use of DXA has increased in recent years, with a wide held belief that it is the criterion standard. When bone mineral content needs to be assessed, and/or when it is necessary to take limb-specific estimations of fat and fat-free mass, then DXA appears to be the preferred method, although it is crucial to be aware of the logistical constraints required to produce reliable data, including controlling food intake, prior exercise and hydration status. However, given the need for simplicity and after considering the evidence across all assessment methods, skinfolds appear to be the least affected by day-to-day variability, leading to the conclusion 'come back skinfolds, all is forgiven'.

Dual-energy X-ray absorptiometry (DXA) has been considered a reference method for measuring body fat percentage (BF%) in children and adolescents with an excess of adiposity. However, given that the DXA technique is impractical for routine field use, there is a need to investigate other methods that can accurately determine BF%. We studied the accuracy of bioelectrical impedance analysis (BIA) technology, including foot-to-foot and hand-to-foot impedance, and Slaughter skinfold-thickness equations in the measurement of BF%, compared with DXA, in a population of Latin American children and adolescents with an excess of adiposity. A total of 127 children and adolescents (11⁻17 years of age; 70% girls) from the HEPAFIT (Exercise Training and Hepatic Metabolism in Overweight/Obese Adolescent) study were included in the present work. BF% was measured on the same day using two BIA analysers (Seca® 206, Allers Hamburg, Germany and Model Tanita® BC-418®, TANITA Corporation, Sportlife Tokyo, Japan), skinfold measurements (Slaughter equation), and DXA (Hologic Horizon DXA System®, Quirugil, Bogotá, Columbia). Agreement between measurements was analysed using t-tests, Bland⁻Altman plots, and Lin's concordance correlation coefficient (ρc). There was a significant correlation between DXA and the other BF% measurement methods (r > 0.430). According to paired t-tests, in both sexes, BF% assessed by BIA analysers or Slaughter equations differ from BF% assessed by DXA (p ® mBCA, Tanita® BC 420MA, and Slaughter equations, respectively. Concordance was poor between DXA and the other methods of measuring BF% (ρc < 0.5). BIA analysers and Slaughter equations underestimated BF% measurements compared to DXA, so they are not interchangeable methods for assessing BF% in Latin American children and adolescents with excess of adiposity.

Skinfold thickness assessment is one of the most widely used anthropometric methods for estimating subcutaneous adipose tissue and overall body adiposity in clinical, epidemiological, and sports settings. Despite its long-standing application, substantial heterogeneity persists across measurement protocols and standardization systems, potentially affecting reproducibility and comparability across studies. This narrative review aims to critically synthesize the historical, conceptual, methodological, and technical development of the main skinfold measurement protocols and standards, systematically compare their characteristics, and examine their methodological and practical implications for research and clinical applications. A targeted bibliographic synthesis of classic textbooks, consensus manuals, and original peer-reviewed studies on surface anthropometry was conducted. Seventeen anatomical skinfold sites and 31 distinct technical descriptions were identified, including 22 site-selection protocols and 9 measurement standards. Five established standards were comparatively analyzed, with emphasis on anatomical landmarking, fold orientation, spatial pinching procedures, and temporal reading control. Similarities were observed in general technical principles, including right-side assessment, perpendicular caliper application, controlled reading time, and maintenance of fold elevation. However, persistent divergences were identified in anatomical definitions, fold orientation, landmark precision, spatial positioning of pinch and caliper jaws, and recommended reading time, with greater heterogeneity at trunk sites than limb sites. Although the reviewed protocols and standards were developed for broad application across age groups, this review primarily reflected their use in adolescents and adults, as skinfold assessment in infants and young children involves additional considerations related to growth dynamics and rapid changes in adipose tissue. Skinfold measurement protocols and standards are not interchangeable and reflect pluralistic, complementary international initiatives rather than a single institutional standardization process.