In spite of the number of participants in soccer, it would appear that there is no specific physical, motor, anthropometric and sport psychological profile by which soccer players can be evaluated to determine whether they comply with the specific requirements of soccer. Therefore, the purpose of this study was to determine which physical, motor performance, anthropometric and sport psychological variables distinguish soccer teams of different participation levels. Fifteen Uniwest (classed as successful), twelve Vaal Triangle Technikon (classed as less successful) and sixteen North-West Sports Academy players (classed as the developmental team) were subjected to a test battery that consisted of 8 physical and motor tests as well as 14 anthropometric measurements. Only two teams (Uniwest and Vaal Triangle Technikon) completed the CSAI-2, AMSSE, ACSI-28 and PVI sport psychological questionnaires. The results of the stepwise forward discriminant analysis showed that isokinetic dorsi and plantarflexion peak torque, together with right hamstring flexibility, agility, muscle mass percentage, speed over 5m and abdominal muscle strength, were the physical, motor performance and anthropometric test variables which significantly (p ≤0.05) and accurately (94.74%) distinguish between soccer teams of different participation levels. The results of the sport psychological variables revealed that goal directedness, concentration, optimal performance under pressure, goal setting, performance motivation and activation control are the variables that have an 86.1 1% success rate in discriminating between successful and less-successful soccer players. In conclusion, although the potential of a physical, motor performance, anthropometric and sport psychological test battery to discriminate accurately between soccer players of different participation levels can not be discounted, it appears that the successful soccer team will not necessarily achieve better test battery results than players of other participation levels. The successful group only obtained significantly better results in 4 variables (speed over 5, 10 and 20m as well as striving for success) when compared to the less successful group, who achieved significantly better results in 16 variables. / Thesis (M.Sc. (Human Movement Science))--North-West University, Potchefstroom Campus, 2005.

Thesis studied correlations between swallowing accelerometry parameters and anthropometrics in 50 healthy participants. Anthropometrics include: age, gender, weight, height, body fat percent, neck circumference and mandibular length. Dual-axis swallowing signals, from a biaxial accelerometer were obtained for 5-saliva and 10-water (5-wet and 5-wet chin-tuck) swallows per participant. Two patient-independent automatic segmentation algorithms using discrete wavelet transforms of swallowing sequences segmented: 1) saliva/wet swallows and 2) wet chin-tuck swallows. Extraction of swallows hinged on dynamic thresholding based on signal statistics. Canonical correlation analysis was performed on sets of anthropometric and swallowing signal variables including: variance, skewness, kurtosis, autocorrelation decay time, energy, scale and peak-amplitude. For wet swallows, significant linear relationships were found between signal and anthropometric variables. In superior-inferior directions, correlations linked weight, age and gender to skewness and signal-memory. In anterior-posterior directions, age was correlated with kurtosis and signal-memory. No significant relationship was observed for dry and wet chin-tuck swallowing

Sex steroids influence the storing of fat, and differences in the distribution of fat are a typical secondary sexual characteristic. Androgens act on fatty tissues in males either directly through stimulation of the androgen receptor or indirectly through aromatization of the estrogen receptor. Androgens can be classified as aromatizable or non-aromatizable. Testosterone (T) is the main aromatizable androgen, while its metabolite dihydrotestosterone (DHT) is a non-aromatizable androgen that acts only through the androgen receptor. It is precisely this difference in having activity only through the androgen receptor that has given rise to the hypothesis concerning the differing effects of DHT and T on body composition, with DHT possibly being responsible for male-type fat distribution. As part of my post-graduate studies we analyzed the dependence serum levels of T and DHT on age, as well as changes in their ratio with age. Further, we sought relationships between aromatizable and non-aromatizable androgens and metabolic and anthropometric parameters. We also focused on following any changes in steroidogenesis in obese males. We showed that before puberty the dominant androgen is rather DHT than T, that the fDHT/fT ratio during the life of adult males is constant, and that there is no evidence of a reversal...

Sex steroids influence the storing of fat, and differences in the distribution of fat are a typical secondary sexual characteristic. Androgens act on fatty tissues in males either directly through stimulation of the androgen receptor or indirectly through aromatization of the estrogen receptor. Androgens can be classified as aromatizable or non-aromatizable. Testosterone (T) is the main aromatizable androgen, while its metabolite dihydrotestosterone (DHT) is a non-aromatizable androgen that acts only through the androgen receptor. It is precisely this difference in having activity only through the androgen receptor that has given rise to the hypothesis concerning the differing effects of DHT and T on body composition, with DHT possibly being responsible for male-type fat distribution. As part of my post-graduate studies we analyzed the dependence serum levels of T and DHT on age, as well as changes in their ratio with age. Further, we sought relationships between aromatizable and non-aromatizable androgens and metabolic and anthropometric parameters. We also focused on following any changes in steroidogenesis in obese males. We showed that before puberty the dominant androgen is rather DHT than T, that the fDHT/fT ratio during the life of adult males is constant, and that there is no evidence of a reversal...

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No description available.

[ES] Los problemas de selección de talla y ajuste en la compra online de ropa son la causa de aproximadamente el 70% de las devoluciones. Esto se debe principalmente a la falta de estandarización del tallaje y al funcionamiento deficiente de los métodos de recomendación de talla. Actualmente, el comercio online de ropa tiene mucho potencial, sin embargo, las elevadas tasas de devolución, suponen costes relevantes en logística y gestión de stocks. En el estado del arte de esta tesis se refleja la complejidad del problema del ajuste de ropa, en el que intervienen múltiples factores tanto objetivos (tipo de tejido, patronaje, número de tallas, moda, morfotipo del usuario, medidas corporales, etc.), como subjetivos (percepción de ajuste y preferencias del usuario). Siendo el ajuste de las prendas uno de los problemas de mayor relevancia en el sector de la confección es de crucial interés avanzar en la generación de un conocimiento que permita relacionar con mayor precisión las dimensiones corporales, el ajuste de las prendas y el tallaje. El objetivo general de esta tesis consiste en establecer los fundamentos para desarrollar un sistema de recomendación del ajuste y talla de prendas de ropa a partir de medidas antropométricas del usuario y valoraciones de ajuste planteando un desarrollo metodológico que sirve de punto de partida para posteriormente escalar el proceso a cualquier tipo de prenda, estilo y sistema de tallaje de ropa. La aproximación propuesta consiste en la predicción del ajuste por zonas de la prenda a partir de medidas antropométricas del usuario y pruebas de ajuste previas utilizando el método estadístico de regresión logística multinomial. A partir de esta predicción de ajuste por zonas, y aplicando de nuevo modelos de regresión logística multinomial, se obtiene la probabilidad de ajuste de la serie de tallas de la prenda analizada. En primer lugar, se ha determinado la fiabilidad de las medidas antropométricas obtenidas a partir de escaneados 3D del cuerpo. Para desarrollar los modelos de predicción, se ha puesto a punto un método de caracterización del ajuste de ropa mediante valoración subjetiva de usurarios y expertos. Además, se han definido los conjuntos de medidas antropométricas relacionadas con el ajuste de la prenda en cada zona. El proceso de entrenamiento de los modelos de predicción de ajuste ha permitido determinar cuáles son las medidas antropométricas más relevantes para el ajuste de cada tipo de prenda, así como las zonas de ajuste que influyen en la selección de la talla. En la fase de validación, se ha demostrado que, con un porcentaje de acierto entre el 80-100%, los modelos de predicción de talla basados en probabilidades de ajuste obtenidas mediante regresión logística multinomial en zonas relevantes de la prenda, ofrecen mayor fiabilidad que los métodos actuales que solo consideran una variable corporal y sus intervalos. Finalmente, se ha propuesto un método para extrapolar los modelos individuales de predicción de talla a toda población objetivo, estimar la cuota de mercado potencial y optimizar la distribución de tallas de cada prenda. / [CA] Els problemes de selecció de talla i ajust en les compres de roba en la xarxa representen aproximadament el 70% de les devolucions. Això es degut principalment a la manca d'estandardització en les talles i al funcionament deficient dels mètodes de recomanació de talles. Actualment, el comerç de roba en la xarxa té molt potencial, no obstant això, les altes taxes de devolució comporten costos rellevants en logística i gestió d'estocs. L'estat de l'art en aquesta tesi reflecteix la complexitat del problema de l'ajust de la roba, que implica múltiples factors, tant objectius (tipus de teixit, patró, nombre de talles, tendències de moda, tipus de cos de l'usuari, mesures corporals, etc.) com subjectius (percepció de l'ajust per part de l'usuari i preferències). Ja que l'ajust de les peces de vestir és un dels problemes més importants en la indústria de la moda, és crucial avançar en la generació de coneixement que permeti establir una relació més precisa entre les dimensions del cos, l'ajust de la roba i les talles. L'objectiu general d'aquesta tesi és establir els fonaments per al desenvolupament d'un sistema de recomanació de l'ajust i la talla de peces de roba basat en les mesures antropomètriques de l'usuari. Això implica un desenvolupament metodològic que serveix com a punt de partida per a posteriorment escalar el procés a qualsevol tipus de peça de roba, estil i sistema de mides. L'aproximació proposada consistix en predir l'ajust per zones de la peça de roba basat en les mesures antropomètriques de l'usuari i proves prèvies d'ajust mitjançant el mètode estadístic de la regressió logística multinomial. A partir d'aquesta predicció d'ajust per zones, i aplicant novament models de regressió logística multinomial, s'obté la probabilitat d'ajust per a la gamma de talles de la peça de roba analitzada. S'ha determinat la fiabilitat de les mesures antropomètriques obtingudes a partir d'escaneigs 3D del cos. Per desenvolupar els models de predicció, s'ha posat a punt un mètode per caracteritzar l'ajust de la roba mitjançant avaluacions subjectives dels usuaris i experts. A més, s'han definit conjunts de mesures antropomètriques relacionades amb l'ajust de la peça a cada zona. El procés de formació dels models de predicció de l'ajust ha permès determinar les mesures antropomètriques més rellevants per a l'ajust de cada tipus de peça, així com les zones d'ajust que influeixen en la selecció de la talla. En la fase de validació, s'ha demostrat que, amb un percentatge d'encert entre el 80-100%, els models de predicció de talla basats en les probabilitats d'ajust obtingudes mitjançant la regressió logística multinomial en zones rellevants de la peça de roba ofereixen una major fiabilitat que els mètodes actuals que només consideren una variable corporal i els seus intervals. Finalment, s'ha proposat un mètode per extrapol·lar els models individuals de predicció de talla a tota la població objectiu, estimar la quota de mercat potencial i optimitzar la distribució de talles per a cada peça. / [EN] The problems of size selection and fit in online clothing purchases account for approximately 70% of returns. This is primarily due to the lack of standardization in sizing and the inefficient performance of current size recommendation methods. Currently, online clothing retail has a lot of potential; however, the high product return rates result in significant costs in logistics and stock management. The state of the art in this thesis reflects the complexity of the clothing fit problem, which involves multiple factors, both objective (fabric type, pattern, number of sizes, fashion trends, user body type, body measurements, etc.) and subjective (user's perception of fit and preferences). Since garment fit is one of the most significant issues in the fashion industry, it is crucial to advance in generating knowledge that allows for a more precise relationship between body dimensions, garment fit, and sizing. The general objective of this thesis is to establish the foundations for developing a recommendation system for clothing fit and size based on user anthropometric measurements and fit evaluations. This involves a methodological development that serves as a starting point for subsequently scaling the process to any type of garment, style, and sizing system. The proposed approach consists of predicting the fit by garment zones based on user anthropometric measurements and previous fit trials using the statistical method of multinomial logistic regression. From this prediction of fit by zones, and by once again applying multinomial logistic regression models, the probability of fit for the range of sizes of the analyzed garment is obtained. The reliability of anthropometric measurements obtained from 3D body scans has been determined. To develop the prediction models, a method for characterizing garment fit through subjective assessments by users and experts has been refined. In addition, sets of anthropometric measurements related to garment fit in each zone have been defined. The training process of the fit prediction models has enabled determining the most relevant anthropometric measurements for the fit of each type of garment, as well as the fit zones that influence size selection. In the validation phase, it has been demonstrated that, with an accuracy rate between 80-100%, size prediction models based on fit probabilities obtained through multinomial logistic regression in relevant garment zones offer greater reliability than current methods that only consider a single body variable and its intervals. Finally, a method has been proposed to extrapolate individual size prediction models to the entire target population, estimate the potential market share, and optimize the distribution of sizes for each garment. / Alemany Mut, MS. (2023). Desarrollo de modelos estadísticos de predicción del ajuste y talla de prendas de ropa a partir de la percepción y características antropométricas del usuario [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/202617

The measurement of cardiorespiratory fitness has been extensively researched among adult populations, but very few researchers have focused their attention on the cardiorespiratory fitness of children and adolescents. Due to various constraints of direct 2max VO testing, various indirect testing methods have been developed of which the 20-m Shuttle Run Test is the most widely used testing method. The influence of various anthropometric, physical and motor performance components as well as certain demographic factors such as gender, race, living area, and sport participation as well as physical activity level on the 2max VO value of participants seems to suggest that 2max VO can be predicted by including these components in prediction models. It is against this background that the objectives of this study are provided. The following four objectives of the study were achieved through a literature review: Firstly, to name and describe the various direct and indirect methods for determining 2max VO ; secondly, to provide a review on the findings with regard to the aerobic performances or 2max VO values of children and adolescents; thirdly, to discuss the possible influence of various anthropometric, physical and motor-performance components on the aerobic performances or 2max VO values of the last-mentioned groups of subjects. As part of this objective, other literature-identified factors such as certain demographic factors (living area, race and gender), sport and physical activity participation level which may also influence the aerobic performances or 2max VO values of the participants, were also discussed; fourthly, all literature identified models for the prediction of aerobic performances or 2max VO values in children, and in adolescents were mentioned and discussed. The next few objectives were achieved through a selected group, cross-sectional experimental research design; fifthly, to develop a valid 2max VO prediction function from several anthropometric measurements and demographic factors such as gender, race and living area as well as sport participation level of a cohort of adolescents living in the Tlokwe Local Municipality (Potchefstroom area) of North West Province, South Africa; sixthly, to develop a 2max VO prediction function from the physical and motor-performance components as well as demographic variables such as gender, race and living area as well as sport participation level of a cohort of adolescents living in the Tlokwe Local Municipality (Potchefstroom area) of North West Province, South Africa; and finally, to determine the validity of the 20-m SRT to estimate the 2 VO and 2max VO of a cohort of adolescent boys in the Tlokwe Local Municipality (Potchefstroom area) of North West Province, South Africa. In order to fulfil the fifth and sixth objectives of the study, a total of 214 grade 8 adolescents (boys: 88 and girls: 126) (age: 15.82 ± 0.68 years) of high schools in the Tlokwe Local Municipality (Potchefstroom area) of the Dr Kenneth Kaunda District of the North West Province, South Africa were purposefully selected from pre-acquired class lists, from six secondary schools. Data was collected by means of various questionnaires, anthropometric measurements and physical and motor-performance tests, which also included the 20-metre SRT. For the fulfilment of the final objective of the study, 52 boys were purposefully selected from the above-mentioned group that completed various questionnaires as well as the 20-m SRT while they were fitted with a portable gas analyser apparatus. With regard to the anthropometric and demographic variable prediction model, the forward stepwise regression analysis results showed that muscle mass percentage, sport participation level, stature, hip circumference and ectomorphy act as significant predictors (p ≤ 0.05) of the indirect, 20-m SRT 2max VO values of a cohort of adolescents. Muscle mass percentage emerged as the strongest predictor (59%) of adolescents’ 2max VO values, followed by sport participation level (6%), ectomorphy (2%), stature (1%) and hip circumference (1%). The physical, motor-performance and demographic prediction model revealed that 10-metre speed, sit-up repetitions, sport participation level, handgrip strength, Vertical Jump Test (VJT) Tendo peak power, maximal heart rate (HRmax), living area, right shoulder external rotation flexibility (RPSERT), horizontal jump test distance (HJT) and right Modified Thomas iliopsoas flexibility (RMTIT) served as significant predictors (p ≤ 0.05) of the indirect, 20m-SRT-derived 2max VO values of a cohort of adolescents. However, only 10-metre speed served as a major contributor (53.5%) to the indirect 2max VO values of the adolescents. The rest of the variables contributed 17.4% to the overall variance in 2maxVO values. Overall, the last-mentioned anthropometric, physical, motor performance and demographic variables were responsible for 70.5% of the variance in the 2max VO values of the adolescents. Cross-validations also revealed that both models are valid for predicting the 20-m SRT-derived indirect 2max VO values of this cohort of adolescents. The 20-m SRT validity study showed that a significant difference (p ≤ 0.05) existed between the predicted indirect 2max VO results (42.06 ± 4.53 ml/kg/min) as obtained from the 20-m SRT booklet and the direct 2max VO results (50.62 ± 7.11 ml/kg/min) as obtained from the gas analysis. Furthermore, significant differences (p ≤ 0.05) were observed between the direct and indirectly predicted 2 VO values at levels 1-9 of the 20-m SRT compared to no significant differences at levels 10 and 11 of the 20-m SRT. In conclusion, to the researchers’ knowledge, this is the first study to develop valid 2max VO prediction functions from the use of several anthropometric measurements, physical and motorperformance test results and demographic information for a group of South African adolescents. Furthermore, this is also the first study to reveal that the 20-m SRT is not a valid test for the accurate prediction of 2 VO and 2max VO of a cohort of adolescent South African boys. The results of this study may possibly allow practitioners in the field of Human Movement Science to more accurately screen the indirect 2max VO values of adolescents by making use of easily obtainable measures and information, instead of the predicted 2max VO values of the 20-m SRT / PhD (Human Movement Science), North-West University, Potchefstroom Campus, 2014

The measurement of cardiorespiratory fitness has been extensively researched among adult populations, but very few researchers have focused their attention on the cardiorespiratory fitness of children and adolescents. Due to various constraints of direct 2max VO testing, various indirect testing methods have been developed of which the 20-m Shuttle Run Test is the most widely used testing method. The influence of various anthropometric, physical and motor performance components as well as certain demographic factors such as gender, race, living area, and sport participation as well as physical activity level on the 2max VO value of participants seems to suggest that 2max VO can be predicted by including these components in prediction models. It is against this background that the objectives of this study are provided. The following four objectives of the study were achieved through a literature review: Firstly, to name and describe the various direct and indirect methods for determining 2max VO ; secondly, to provide a review on the findings with regard to the aerobic performances or 2max VO values of children and adolescents; thirdly, to discuss the possible influence of various anthropometric, physical and motor-performance components on the aerobic performances or 2max VO values of the last-mentioned groups of subjects. As part of this objective, other literature-identified factors such as certain demographic factors (living area, race and gender), sport and physical activity participation level which may also influence the aerobic performances or 2max VO values of the participants, were also discussed; fourthly, all literature identified models for the prediction of aerobic performances or 2max VO values in children, and in adolescents were mentioned and discussed. The next few objectives were achieved through a selected group, cross-sectional experimental research design; fifthly, to develop a valid 2max VO prediction function from several anthropometric measurements and demographic factors such as gender, race and living area as well as sport participation level of a cohort of adolescents living in the Tlokwe Local Municipality (Potchefstroom area) of North West Province, South Africa; sixthly, to develop a 2max VO prediction function from the physical and motor-performance components as well as demographic variables such as gender, race and living area as well as sport participation level of a cohort of adolescents living in the Tlokwe Local Municipality (Potchefstroom area) of North West Province, South Africa; and finally, to determine the validity of the 20-m SRT to estimate the 2 VO and 2max VO of a cohort of adolescent boys in the Tlokwe Local Municipality (Potchefstroom area) of North West Province, South Africa. In order to fulfil the fifth and sixth objectives of the study, a total of 214 grade 8 adolescents (boys: 88 and girls: 126) (age: 15.82 ± 0.68 years) of high schools in the Tlokwe Local Municipality (Potchefstroom area) of the Dr Kenneth Kaunda District of the North West Province, South Africa were purposefully selected from pre-acquired class lists, from six secondary schools. Data was collected by means of various questionnaires, anthropometric measurements and physical and motor-performance tests, which also included the 20-metre SRT. For the fulfilment of the final objective of the study, 52 boys were purposefully selected from the above-mentioned group that completed various questionnaires as well as the 20-m SRT while they were fitted with a portable gas analyser apparatus. With regard to the anthropometric and demographic variable prediction model, the forward stepwise regression analysis results showed that muscle mass percentage, sport participation level, stature, hip circumference and ectomorphy act as significant predictors (p ≤ 0.05) of the indirect, 20-m SRT 2max VO values of a cohort of adolescents. Muscle mass percentage emerged as the strongest predictor (59%) of adolescents’ 2max VO values, followed by sport participation level (6%), ectomorphy (2%), stature (1%) and hip circumference (1%). The physical, motor-performance and demographic prediction model revealed that 10-metre speed, sit-up repetitions, sport participation level, handgrip strength, Vertical Jump Test (VJT) Tendo peak power, maximal heart rate (HRmax), living area, right shoulder external rotation flexibility (RPSERT), horizontal jump test distance (HJT) and right Modified Thomas iliopsoas flexibility (RMTIT) served as significant predictors (p ≤ 0.05) of the indirect, 20m-SRT-derived 2max VO values of a cohort of adolescents. However, only 10-metre speed served as a major contributor (53.5%) to the indirect 2max VO values of the adolescents. The rest of the variables contributed 17.4% to the overall variance in 2maxVO values. Overall, the last-mentioned anthropometric, physical, motor performance and demographic variables were responsible for 70.5% of the variance in the 2max VO values of the adolescents. Cross-validations also revealed that both models are valid for predicting the 20-m SRT-derived indirect 2max VO values of this cohort of adolescents. The 20-m SRT validity study showed that a significant difference (p ≤ 0.05) existed between the predicted indirect 2max VO results (42.06 ± 4.53 ml/kg/min) as obtained from the 20-m SRT booklet and the direct 2max VO results (50.62 ± 7.11 ml/kg/min) as obtained from the gas analysis. Furthermore, significant differences (p ≤ 0.05) were observed between the direct and indirectly predicted 2 VO values at levels 1-9 of the 20-m SRT compared to no significant differences at levels 10 and 11 of the 20-m SRT. In conclusion, to the researchers’ knowledge, this is the first study to develop valid 2max VO prediction functions from the use of several anthropometric measurements, physical and motorperformance test results and demographic information for a group of South African adolescents. Furthermore, this is also the first study to reveal that the 20-m SRT is not a valid test for the accurate prediction of 2 VO and 2max VO of a cohort of adolescent South African boys. The results of this study may possibly allow practitioners in the field of Human Movement Science to more accurately screen the indirect 2max VO values of adolescents by making use of easily obtainable measures and information, instead of the predicted 2max VO values of the 20-m SRT / PhD (Human Movement Science), North-West University, Potchefstroom Campus, 2014

The scale of the current global obesity epidemic and the implications of this for health, functionality and economics, dictates that assessing the origins of overnutrition must become a priority in all research fields. To date anthropometric historians have mainly utilised institutional sources providing height and occasionally weight data for a sample of the working class who experienced deprivation. Tailoring institutions offer new, innovative sources for the field; uniquely measuring body shape in its entirety and sampling the upper-middle classes and elites. Anthropometric data for waist circumference, hip circumference and leg length has been collected from Morris & Son tailoring establishment in Barmouth, North West Wales and from Henry Poole & Co. ‘Savile Row’ tailors in Mayfair, London. This data from the second half of the nineteenth century has been nominally linked to census and probate records and cross-referenced with contemporary medical tracts and modern epidemiological literature to highlight obesity related health risks within both populations. Results indicate that 'diseases of affluence' permeated many nineteenth century class groups. Both waist circumferences and hip circumferences increased over the life span. Furthermore, Barmouth’s economic transition from a port to a tourist destination appears to have placed individuals' health (when measured by early adult waist-hip ratio) at greater risk than the overall wealthier customers attending Savile Row. The Barker hypothesis may be relevant - an influx of wealth being of greater detriment to health in later life than consistent affluence. For Henry Poole & Co.’s customers an elite lifestyle enabled girths to expand, increasing the risk of chronic diseases but seemingly protecting them from infectious pathogens. In later life, during the second half of the nineteenth century, it would appear that optimal waist circumferences to reduce mortality were larger than current recommended levels.