Ketogenic diet-induced weight loss is associated with an increase in vitamin d levels in obese adults

Vitamin D is an important micronutrient involved in several processes. Evidence has shown a strong association between hypovitaminosis D and cardio-metabolic diseases, including obesity. A ketogenic diet has proven to be very effective for weight loss, especially in reducing fat mass while preserving fat-free mass. The aim of this study was to investigate the effect of a ketogenic diet-induced weight loss on vitamin D status in a population of obese adults. We enrolled 56 obese outpatients, prescribed with either traditional standard hypocaloric Mediterranean diet (SHMD) or very low-calorie ketogenic diet (VLCKD). Serum 25(OH)D concentrations were measured by chemiluminescence. The mean value of serum 25-hydroxyvitamin D (25(OH)D) concentrations in the whole population at baseline was 17.8 +/- 5.6 ng/mL, without differences between groups. After 12 months of dietetic treatment, in VLCKD patients serum 25(OH)D concentrations increased from 18.4 +/- 5.9 to 29.3 +/- 6.8 ng/mL (p < 0.0001), vs 17.5 +/- 6.1 to 21.3 +/- 7.6 ng/mL (p = 0.067) in the SHMD group (for each kilogram of weight loss, 25(OH)D concentration increased 0.39 and 0.13 ng/mL in the VLCKD and in the SHMD groups, respectively). In the VLCKD group, the increase in serum 25(OH)D concentrations was strongly associated with body mass index, waist circumference, and fatty mass variation. In a multiple regression analysis, fatty mass was the strongest independent predictor of serum 25(OH)D concentration, explaining 15.6%, 3.3%, and 9.4% of its variation in the whole population, in SHMD, and VLCKD groups, respectively. We also observed a greater reduction of inflammation (evaluated by high-sensitivity C reactive protein (hsCRP) values) and a greater improvement in glucose homeostasis, confirmed by a reduction of HOMA values, in the VLCKD versus the SHMD group. Taken together, all these data suggest that a dietetic regimen, which implies a great reduction of fat mass, can improve vitamin D status in the obese

Relationship between anthropometric variables and body image dissatisfaction among fitness center users

The purpose of this study was to identify the anthropometric dimensions related with body image dissatisfaction among fitness center users. Participants were 276 Brazilian members of fitness centers (168 males and 108 females) with ages between 17 and 39 years (mage = 23.93, sd = 5.17). After body mass (BM), body mass index (BMI) and body fat (% BF) were measured, participants indicated their current (cs) and ideal (Is) silhouettes, allowing the calculation of body dissatisfaction as the difference between Is and cs. BMI and % BF were grouped by body dissatisfaction category and analyzed using one-way and repeated measures ANoVA. results revealed that only 1.2 % of men and 6.5 % of women considered themselves satisfied with their body. comparisons of global ratings of their cs and Is revealed that male and female individuals reported that their current bodies were significantly less muscular than their ideal bodies (p < .001), although the degree of dissatisfaction revealed no significant difference between sexes. Moreover, results demonstrated that the relationship between body composition and body dissatisfaction only occurs in individuals that feel very dissatisfied with their body image and appearance

Physical development, and progression to professional soccer, of elite child and adolescent academy players

The research described within this thesis was undertaken to investigate the physical development, and progression to professional soccer, of elite child and adolescent academy players. Firstly, a detailed understanding of professional practitioners perceptions of physical performance in soccer was developed. Secondly, a valid and reliable battery of physical field tests was established to examine the physical performance characteristics of elite child and adolescent soccer players. Finally, this battery of physical performance tests was administered to elite child and adolescent players in English professional soccer academies over a three year period. Coaches (n=170), fitness professionals (n=172) and players (n=101) perceptions of physical performance in soccer were assessed by means of a questionnaire. Speed was considered the principle physical attribute by coaches, with 80.5% deeming it as very important . Most coaches (88.8%), fitness professionals (93.0%) and players (89.1%) believed the relative importance of each physical attribute differed according to playing position. A players physical attributes were regarded by coaches as important (44.1%) and very important (41.8%) in the process of offering professional playing contracts. Most coaches (71.2%), fitness professionals (68.6%) and players (65.3%) thought international players physical attributes were different to club players. Nearly all coaches (93.5%), fitness professionals (86.6%) and players (83.2%) believed the physical attributes of players had become more important in the modern day game. It was widely considered by coaches (73.5%), fitness professionals (52.9%) and players (74.3%) that players from certain ethnic groups were naturally more physically able. Logical validity of physical performance testing was demonstrated by the majority of coaches (97.0%), fitness professionals (93.5%) and players (83.1%) considering testing to be an important aspect of preparation in soccer. Construct validity of vertical jump (RJ; CMJ; CMJA), sprint (10 m and 20 m) and agility tests was shown by their ability to distinguish between different age groups (p<0.01) and ability groups (p<0.05) of players. Absolute reliability of the physical performance tests was established with repeatability on the vertical jump tests ranging from 3.2 cm to 3.5 cm for the RJ and CMJA, respectively, whilst repeatability on the sprint tests ranged from 0.07 s to 0.24 s on the 10 m sprint and agility test, respectively. ICC and PCC values to assess the relative reliability of the physical performance tests were all high (>0.90) ranging from 0.96 for the agility test to 0.99 for the 20 m sprint

A single weekly Kt/Vurea target for peritoneal dialysis patients does not provide an equal dialysis dose for all

Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.Dialysis adequacy is traditionally based on urea clearance, adjusted for total body volume (Kt/Vurea), and clinical guidelines recommend a Kt/Vurea target for peritoneal dialysis. We wished to determine whether adjusting dialysis dose by resting and total energy expenditure would alter the delivered dialysis dose. The resting and total energy expenditures were determined by equations based on doubly labeled isotopic water studies and adjusted Kturea for resting energy expenditure and total energy expenditure in 148 peritoneal dialysis patients (mean age, 60.6 years; 97 male [65.5%]; 54 diabetic [36.5%]). The mean resting energy expenditure was 1534 kcal/d, and the total energy expenditure was 1974 kcal/day. Using a weekly target Kt/V of 1.7, Kt was calculated using V measured by bioimpedance and the significantly associated (r = 0.67) Watson equation for total body water. Adjusting Kt for resting energy expenditure showed a reduced delivered dialysis dose (ml/kcal per day) for women versus men (5.5 vs. 6.2), age under versus over 65 years (5.6 vs. 6.4), weight 80 kg (5.8 vs. 6.1), low versus high comorbidity (5.9 vs. 6.2), all of which were significant. Adjusting for the total energy expenditure showed significantly reduced dosing for those employed versus not employed (4.3 vs. 4.8), a low versus high frailty score (4.5 vs. 5.0) and nondiabetic versus diabetic (4.6 vs. 4.9). Thus, the current paradigm for a single target Kt/Vurea for all peritoneal dialysis patients does not take into account energy expenditure and metabolic rate and may lead to lowered dialysis delivery for the younger, more active female patient.Peer reviewedFinal Accepted Versio

How health-related behaviors predict body-esteem in men

While there is a general consensus on the biological implications of health-related behaviors, there is little research on the implications of health-related behaviors on body-esteem in a nonclinical population of men. This study aimed to examine, using a multidimensional measure of health-related behaviors and controlling for body mass index (BMI), whether body-esteem in men can be predicted by health-related behaviors. Five hundred and sixty-one men between the ages of 30 and 45 years (M = 35.42, SD = 4.41) completed the Body-Esteem Scale (BES), the Health Behaviour Inventory (HBI), and a questionnaire covering anthropometric measures including height and weight. Multiple regression analyses revealed that health-related behaviors (including positive nutrition habits, positive attitude, and healthy practices) significantly predicted body-esteem, R2adj = 0.05, F(5, 540) = 6.91, p < .001. The results are discussed in relation to healthy lifestyle promotion interventions targeting men

Hand Grip Strength in Students: Differences in the Gender Dimorphism

The hands are anatomically specialized for manipulative tasks with different physical objects, where they can cope with certain loads with different forces and intensity. During various physical and sports activities, the hands produce the appropriate muscular force for gripping, which manifests as the hand grip's force. For this reason, hand grip strength (HGS) is recognized as a limiting factor in all manipulative activities performed by the cranial part of the body. The current research included a sample of 22 subjects, 16 male Body Height (BH=180.28±4.65cm); Body Weight (BW=80.05±9.96kg), Body Mass Index (BMI=24.61±2.74kg/m²) and 6 female subjects Body Height (BH=167.42±11.11cm); Body Weight (BW=64.80±10.09kg); Body Mass Index (BMI=23.02±1.57kg/m²) on the third year of study at the Faculty of Physical Education and Sports. This study aimed to determine the maximum isometric muscle force of the handgrip and differences between the same gender of students. A t-test for small samples was applied for data processing, and the relevant statistical parameters were calculated. The obtained t-test results confirmed statistically significant differences between the so-called dominant and non-dominant hands in male subjects (t=4.158; p&lt;0.05) and female subjects (t=3.176; p&lt;0.05). The obtained results of this research will be used for analytical and diagnostic purposes with a wide range of activities in the population of physical education and sports students (assessment of physical ability, trends, and tendencies to monitor and change abilities, influence on the implementation of certain curricula of some subjects studied at the faculty, etc.)

Subject-adjustable computational modelling for the analysis of human head–neck motions in rear-end impacts

Whiplash Associated Disorder (WAD) is a general term used to describe minor injuries to the neck, mostly as a result of a rear-end motor vehicle collision. Although the injury is defined as minor, the long-term symptoms such as neck pain, stiffness, headache, or concentration difficulties, result in high costs to the economy, healthcare services and individuals. Consequently, there has been significant amount of research undertaken to understand and prevent WAD, covering experimental and computational studies. However, whiplash injuries are difficult to detect since diagnostic tools such as X-rays, CT (Computed Tomography) scans or MRI (Magnetic Resonance Imaging) are not suitable to identify the location or the extent of the injury. Also, the injury mechanisms are not fully understood; hence mathematical criteria are used as surrogates to estimate the likelihood of injury. In the present research, a biofidelic, subject-adjustable head-and-neck model (i.e. the model is adjustable for individual subject characteristics) has been developed for rear-end impact whiplash analysis. Existing literature is used to develop the overall research framework (methodology), which has three main objectives: first to explain the importance of personalised protection investigations, second to evaluate the suitability of existing data for a subject-adjustable model, and third to define the required steps in the design of such a model.To generate the geometry of the model, previously published cascading equations capable of predicting the main vertebrae dimensions based on the subject characteristics age, gender and height are used. Also, in line with previous work, seven cervical neck segments represent the seven cervical vertebrae and all surrounding cervical tissues properties. The mass and moment of inertia properties of each segment are lumped into each respective segment. The intervertebral behaviour for two adjacent segments is described by non-linear spring-damper functions, which change according to subject specific characteristics. The model is driven by specification of the first thoracic vertebra (T1) motion.The model combines existing data and methods from different sources, utilising available data in the public domain. New procedures and techniques are incorporated to create a homogeneous model, which is adaptable to a wide range of subjects. The developed computational model is not simply a linear scaling of a master-model to other dimensions, but rather uses prediction equations to create the desired anthropometric model. The anthropometric model predictions for body part dimensions and inertia properties are successfully verified using anthropometric surveys available in the literature.Using lumped and non-linear stiffness and damping equations for the intervertebral joints, and without modelling separate muscles, the model is dynamically calibrated for different experimental sled test data available in the open domain. The joint equations and their coefficients are derived based on published joint data measurements on Post Mortem Human Subjects (PMHS); a scaling of these coefficients is applied to match the overall head-and-neck kinematics of the computational model to the experimental sled test kinematics. For each experimental study, the global head kinematics of the model was calibrated successfully to mimic the head kinematics.The model has been modelled to represent subjects with different anthropometric characteristics, involving a novel relationship between intervertebral joint coefficients and anthropometric subject specifications. The observed effect of each change of anthropometric subject characteristic is evaluated independently using time-history diagrams; then the observed effect of multiple changes of anthropometric subject characteristics is assessed using multi-dimensional response surfaces for the response’s highest magnitude.The analysis of the proposed model has revealed that existing work involving the use of lumped parameter models is not as robust as claimed. This is because existing work has always been evaluated using a low number of validation graphs, i.e. using only the graphs which gave good validation results. The proposed model has been comprehensively evaluated and its limitations are addressed. The developed model had to merge different studies (different ethnical backgrounds, different subject types, etc.) together to create an adjustable model; this is because of the limited available data. The final model is the most homogeneous model currently possible. In addition, there is also limited relevant experimental data for full validation of the model, which is not ideal. Nevertheless, reliable results for the comparison of global head kinematics compared with several experimental sled test studies have been obtained for the average male subject model. Also, using the proposed model the dynamic effects resulting from anthropometric subject differences have been evaluated; these effects are almost perfectly linear relationships for each subject characteristic change. Potential applications for the developed model are the injury assessment based on mathematical whiplash injury criteria, head-restraint optimisation to minimise injury risk and the improvement of neck biofidelity in anthropometric test devices.</div

Ergonomics of the Operative Field in Paediatric Minimal Access Surgery

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Kinanthropometry IX

This is an edited collection of peer-reviewed papers presented at the Ninth International Conference of the Society for the Advancement of Kinanthropometry. Defined as the relationship between human body structure and function, kinanthropometry is an area of growing interest, and these proceedings will be of use to students, academics and professionals in the areas of ergonomics, sports science, nutrition, health, and other allied fields. The assembled works represent the latest research findings across kinanthropometry, moving the discipline forward and promoting good practice and the exchange of expertise