Relationships of activity and sugar drink intake on fat mass development in youths

Purpose: To determine whether a significant relationship exists between fat mass (FM) development and physical activity (PA) and/or sugar-sweetened drink (SD) consumption in healthy boys and girls aged 8-19 yr. Methods: A total of 105 males and 103 females were assessed during childhood and adolescence for a maximum of 7 yr and a median of 5 yr. Height was measured biannually. Fat-free mass (FFM) and FM were assessed annually by dual x-ray absorptiometry (DXA). PA was evaluated two to three times annually using the PAQ-C/A. Energy intake and SD were assessed using a 24-h dietary intake questionnaire also completed two to three times per year. Years from peak height velocity were used as a biological maturity age indicator. Multilevel random effects models were used to test the relationship. Results: When controlling for maturation, FFM, and energy intake adjusted for SD, PA level was negatively related to FM development in males (P < 0.05) but not in females (P > 0.05). In contrast, there was no relationship between SD and FM development of males or females (P > 0.05). There was also no interaction effect between SD and PA (P > 0.05) with FM development. Conclusion: This finding tends support to the idea that increasing PA in male youths aids in the control of FM development. Models employed showed no relationship between SD and FM in either gender.

Volumetric and areal bone mineral density measures are associated with cardiovascular disease in older men and women: The health, aging, and body composition study

The associations of volumetric (vBMD) and areal (aBMD) bone mineral density measures with prevalent cardiovascular disease (CVD) and subclinical peripheral arterial disease (PAD) were investigated in a cohort of older men and women enrolled in the Health, Aging, and Body Composition Study. Participants were 3,075 well-functioning white and black men and women (42% black, 51% women), aged 68-80 years. Total hip, femoral neck, and trochanter aBMD were measured using dual-energy X-ray absorptiometry. Quantitative computed tomography was used to evaluate spine trabecular, integral, and cortical vBMD measures in a subgroup (n = 1,489). Logistic regression was performed to examine associations of BMD measures with CVD and PAD. The prevalence of CVD (defined by coronary heart disease, PAD, cerebrovascular disease, or congestive heart failure) was 29.8%. Among participants without CVD, 10% had subclinical PAD (defined as ankle-arm index < 0.9). Spine vBMD measures were inversely associated with CVD in men (odds ratio of integral [ORintegral] = 1.34, 95% confidence interval [CI] 1.10-1.63; ORtrabecular = 1.25, 95% CI 1.02-1.53; ORcortical = 1.36, 95% CI 1.11-1.65). In women, for each standard deviation decrease in integral vBMD, cortical vBMD, or trochanter aBMD, the odds of CVD were significantly increased by 28%, 27%, and 22%, respectively. Total hip aBMD was associated with subclinical PAD in men (OR = 1.39, 95% CI 1.03-1.84) but not in women. All associations were independent of age and shared risk factors between BMD and CVD and were not influenced by inflammatory cytokines (interleukin-6 and tumor necrosis factors-alpha). In conclusion, our results provide further evidence for an inverse association between BMD and CVD in men and women. Future research should investigate common pathophysiological links for osteoporosis and CVD.

Resistance training and reduction of treatment side effects in prostate cancer patients

Purpose: To examine the effect of progressive resistance training on muscle function, functional performance, balance, body composition, and muscle thickness in men receiving androgen deprivation for prostate cancer. Methods: Ten men aged 59-82 yr on androgen deprivation for localized prostate cancer undertook progressive resistance training for 20 wk at 6- to 12-repetition maximum (RM) for 12 upper- and lower-body exercises in a university exercise rehabilitation clinic. Outcome measures included muscle strength and muscle endurance for the upper and lower body, functional performance (repeated chair rise, usual and fast 6-m walk, 6-m backwards walk, stair climb, and 400-m walk time), and balance by sensory organization test. Body composition was measured by dual-energy x-ray absorptiometry and muscle thickness at four anatomical sites by B-mode ultrasound. Blood samples were assessed for prostate specific antigen (PSA), testosterone, growth hormone (GH), cortisol, and hemoglobin. Results: Muscle strength (chest press, 40.5%; seated row, 41.9%; leg press, 96.3%; P < 0.001) and muscle endurance (chest press, 114.9%; leg press, 167.1%; P < 0.001) increased significantly after training. Significant improvement (P < 0.05) occurred in the 6-m usual walk (14.1%), 6-m backwards walk (22.3%), chair rise (26.8%), stair climbing (10.4%), 400-m walk (7.4%), and balance (7.8%). Muscle thickness increased (P < 0.05) by 15.7% at the quadriceps site. Whole-body lean mass was preserved with no change in fat mass. There were no significant changes in PSA, testosterone, GH, cortisol, or hemoglobin. Conclusions: Progressive resistance exercise has beneficial effects on muscle strength, functional performance and balance in older men receiving androgen deprivation for prostate cancer and should be considered to preserve body composition and reduce treatment side effects.

Size-corrected BMD decreases during peak linear growth: Implications for fracture incidence during adolescence

Peak adolescent fracture incidence at the distal end of the radius coincides with a decline in size-corrected BMD in both boys and girls. Peak gains in bone area preceded peak gains in BMC in a longitudinal sample of boys and girls, supporting the theory that the dissociation between skeletal expansion and skeletal mineralization results in a period of relative bone weakness. Introduction: The high incidence of fracture in adolescence may be related to a period of relative skeletal fragility resulting from dissociation between bone expansion and bone mineralization during the growing years. The aim of this study was to examine the relationship between changes in size-corrected BMD (BMDsc) and peak distal radius fracture incidence in boys and girls. Materials and Methods: Subjects were 41 boys and 46 girls measured annually (DXA; Hologic 2000) over the adolescent growth period and again in young adulthood. Ages of peak height velocity (PHV), peak BMC velocity (PBMCV), and peak bone area (BA) velocity (PBAV) were determined for each child. To control for maturational differences, subjects were aligned on PHV. BMDsc was calculated by first regressing the natural logarithms of BMC and BA. The power coefficient (pc) values from this analysis were used as follows: BMDsc = BMC/BA(pc). Results: BMDsc decreased significantly before the age of PHV and then increased until 4 years after PHV. The peak rates in radial fractures (reported from previous work) in both boys and girls coincided with the age of negative velocity in BMDsc; the age of peak BA velocity (PBAV) preceded the age of peak BMC velocity (PBMCV) by 0.5 years in both boys and girls. Conclusions: There is a clear dissociation between PBMCV and PBAV in boys and girls. BMDsc declines before age of PHV before rebounding after PHV. The timing of these events coincides directly with reported fracture rates of the distal end of the radius. Thus, the results support the theory that there is a period of relative skeletal weakness during the adolescent growth period caused, in part, by a draw on cortical bone to meet the mineral demands of the expanding skeleton resulting in a temporary increased fracture risk.

Change in lean body mass Is a major determinant of change in areal bone mineral density of the proximal femur: A 12-year observational study

Our objective was to assess the contribution of lean body mass (LBM) and fat body mass (FBM) to areal bone mineral density (aBMD) in women during the years surrounding menopause. We used a 12-year observational design. Participants included 75 Caucasian women who were premenopausal, 53 of whom were available for follow-up. There were two measurement periods: baseline and 12-year follow-up. At both measurement periods, bone mineral content and aBMD of the proximal femur, posterior-anterior lumbar spine, and total body was assessed using dual-energy X-ray absorptiometry (DXA). LBM and FBM were derived from the total-body scans. General health, including current menopausal status, hormone replace therapy use, medication use, and physical activity, was assessed by questionnaires. At the end of the study, 44% of the women were postmenopausal. After controlling for baseline aBMD, current menopausal status, and current hormone replacement therapy, we found that change in LBM was independently associated with change in aBMD of the proximal femur (P = 0.001). The cross-sectional analyses also indicated that LBM was a significant determinant of aBMD of all three DXA-scanned sites at both baseline and follow-up. These novel longitudinal data highlight the important contribution of LBM to the maintenance of proximal femur bone mass at a key time in women's life span, the years surrounding menopause.

Childhood obesity treatment: integrating mobile health technology into a paediatric obesity service

Background: The management of childhood obesity is challenging. Aims: Thesis, i) reviews the evidence for lifestyle treatment of obesity, ii) explores cardiometabolic burden in childhood obesity, iii) explores whether changes in body composition predicts change in insulin sensitivity (IS), iv) develops and evaluates a lifestyle obesity intervention; v) develops a mobile health application for obesity treatment and vi) tests the application in a clinical trial. Methods: In Study 1, systematic reviews and meta-analyses of the 12‐month effects of lifestyle and mHealth interventions were conducted. In Study 2, the prevalence of cardiometabolic burden was estimated in a consecutive series of 267 children. In Study 3, body composition was estimated with bioelectrical impedance analysis (BIA) and dual x-ray absorptiometry (DXA) and linear regression analyses were used to estimate the extent to which each methods predicted change in IS. Study 4 describes the development of the Temple Street W82GO Healthy Lifestyle intervention for clinical obesity in children and a controlled study of treatment effect in 276 children is reported. Study 5 describes the development and testing of the Reactivate Mobile Obesity Application. Study 6 outlines the development and preliminary report from a clinical effectiveness trial of Reactivate. Results: In Study 1, meta--‐analyses BMI SDS changed by -0.16 (-0.24,‐0.07, p<0.01) and -0.03 (-0.13, 0.06, p=0.48). In study 2, cardiometabolic comorbidities were common (e.g. hypertension in 49%) and prevalence increased as obesity level increased. In Study 3, BC changes significantly predicted changes in IS. In Study 4, BMI SDS was significantly reduced in W82GO compared to controls (p<0.001). In Study 5, the Reactivate application had good usability indices and preliminary 6‐month process report data from Study 6, revealed a promising effect for Reactivate. Conclusions: W82GO and Reactivate are promising forms of treatment.

Adiposity, Sex Hormones, and Repetitive Element DNA Methylation in Healthy Postmenopausal Women

INTRODUCTION: Low levels of methylation within repetitive DNA elements, such as long interspersed nuclear element-1 (LINE-1) and Alu repeats, are believed to epigenetically predispose an individual to cancer and other diseases. The extent to which lifestyle factors affect the degree of DNA methylation within these genomic regions has yet to be fully understood. Adiposity and sex hormones are established risk factors for certain types of cancer and other illnesses, particularly amongst postmenopausal women. The aim of the current investigation is to assess the impact of adiposity and sex hormones on LINE-1 and Alu methylation in healthy postmenopausal women. METHODS: A cross-sectional study was conducted using baseline data from an ancillary study of the Alberta Physical Activity and Breast Cancer Prevention (ALPHA) Trial. Current adiposity was measured using a dual-energy x-ray absorptiometry (DXA) scan, computed tomography (CT) scan, and balance beam scale. Historical weights were self-reported in a questionnaire. Current endogenous sex hormone concentrations were measured in fasting blood serum. Estimated lifetime number of menstrual cycles was used as a proxy for cumulative exposure to ovarian sex hormones. Repetitive element methylation was quantified in white blood cells using a pyrosequencing assay. Linear regression was used to model the relations of interest while adjusting for important confounders. RESULTS: Adiposity and serum estrogen concentrations were positively related to LINE-1 methylation but were not associated with Alu methylation. Cumulative ovarian sex hormone exposure had a “U-shaped” relation with LINE-1 regardless of folate intake and a negative relation with Alu methylation amongst low folate consumers. Androgens were not associated with repetitive element DNA methylation in this population. CONCLUSION: Adiposity and estrogens appear to play a role in maintaining high levels of repetitive element DNA methylation in healthy postmenopausal women. LINE-1 methylation may be a mechanism whereby estrogen exposure protects against cardiovascular and neurodegenerative illnesses. These results add to the growing body of literature showing how the epigenome is shaped by our lifestyle choices. Future prospective studies assessing the relation between levels of repetitive element DNA methylation in healthy individuals and subsequent disease risk are needed to better understand the clinical significance of these results.

Metabolomic profiling to dissect the role of visceral fat in cardiometabolic health

OBJECTIVE: Abdominal obesity is associated with increased risk of type 2 diabetes (T2D) and cardiovascular disease. The aim of this study was to assess whether metabolomic markers of T2D and blood pressure (BP) act on these traits via visceral fat (VF) mass.

METHODS: Metabolomic profiling of 280 fasting plasma metabolites was conducted on 2,401 women from TwinsUK. The overlap was assessed between published metabolites associated with T2D, insulin resistance, or BP and those that were identified to be associated with VF (after adjustment for covariates) measured by dual-energy X-ray absorptiometry.

RESULTS: In addition to glucose, six metabolites were strongly associated with both VF mass and T2D: lactate and branched-chain amino acids, all of them related to metabolism and the tricarboxylic acid cycle; on average, 38.5% of their association with insulin resistance was mediated by their association with VF mass. Five metabolites were associated with BP and VF mass including the inflammation-associated peptide HWESASXX, the steroid hormone androstenedione, lactate, and palmitate. On average, 29% of their effect on BP was mediated by their association with VF mass.

CONCLUSIONS: Little overlap was found between the metabolites associated with BP and those associated with insulin resistance via VF mass.

Assessments of body composition and bone parameters of lactating rats treated with diet containing flaxseed meal (Linum usitatissinum) during post-weaning period

Introduction: There are few studies on body composition and the effects of diet on weight postpartum women. The aim was to evaluate the body composition and bone parameters in lactating rats treated with diet containing flaxseed flour during postweaning period. Methods: After weaning, the lactating rat were divided in control (n = 6) and experimental (F, n = 6) group, treated with 25% flaxseed flour diet. After 30 days, body composition by dual-energy X-ray absorptiometry, serum analysis, organs and intra-abdominal fat mass, femur and lumbar vertebra parameters were determined. Results: The groups showed similar food intake, body mass and bone parameters. While F group showed the following: lower body (-5%), gonadal (-17%), mesenteric (-23%) and intra-abdominal (-6%) fat mass. Increase of HDL-cholesterol (+10%) and lower glucose (-15%), triglycerides (P < 0.05, -37%) and cholesterol (P < 0.05, -21%). Conclusions: The findings highlight the effects of flaxseed for control of adiposity and to maintain a healthy biochemical profile during the postnatal period.

Gait analysis of the hind limb in Labrador Retrievers with and without cranial cruciate ligament disease

Cranial cruciate ligament (CCL) deficiency is the leading cause of lameness affecting the stifle joints of large breed dogs, especially Labrador Retrievers. Although CCL disease has been studied extensively, its exact pathogenesis and the primary cause leading to CCL rupture remain controversial. However, weakening secondary to repetitive microtrauma is currently believed to cause the majority of CCL instabilities diagnosed in dogs. Techniques of gait analysis have become the most productive tools to investigate normal and pathological gait in human and veterinary subjects. The inverse dynamics analysis approach models the limb as a series of connected linkages and integrates morphometric data to yield information about the net joint moment, patterns of muscle power and joint reaction forces. The results of these studies have greatly advanced our understanding of the pathogenesis of joint diseases in humans. A muscular imbalance between the hamstring and quadriceps muscles has been suggested as a cause for anterior cruciate ligament rupture in female athletes. Based on these findings, neuromuscular training programs leading to a relative risk reduction of up to 80% has been designed. In spite of the cost and morbidity associated with CCL disease and its management, very few studies have focused on the inverse dynamics gait analysis of this condition in dogs. The general goals of this research were (1) to further define gait mechanism in Labrador Retrievers with and without CCL-deficiency, (2) to identify individual dogs that are susceptible to CCL disease, and (3) to characterize their gait. The mass, location of the center of mass (COM), and mass moment of inertia of hind limb segments were calculated using a noninvasive method based on computerized tomography of normal and CCL-deficient Labrador Retrievers. Regression models were developed to determine predictive equations to estimate body segment parameters on the basis of simple morphometric measurements, providing a basis for nonterminal studies of inverse dynamics of the hind limbs in Labrador Retrievers. Kinematic, ground reaction forces (GRF) and morphometric data were combined in an inverse dynamics approach to compute hock, stifle and hip net moments, powers and joint reaction forces (JRF) while trotting in normal, CCL-deficient or sound contralateral limbs. Reductions in joint moment, power, and loads observed in CCL-deficient limbs were interpreted as modifications adopted to reduce or avoid painful mobilization of the injured stifle joint. Lameness resulting from CCL disease affected predominantly reaction forces during the braking phase and the extension during push-off. Kinetics also identified a greater joint moment and power of the contralateral limbs compared with normal, particularly of the stifle extensor muscles group, which may correlate with the lameness observed, but also with the predisposition of contralateral limbs to CCL deficiency in dogs. For the first time, surface EMG patterns of major hind limb muscles during trotting gait of healthy Labrador Retrievers were characterized and compared with kinetic and kinematic data of the stifle joint. The use of surface EMG highlighted the co-contraction patterns of the muscles around the stifle joint, which were documented during transition periods between flexion and extension of the joint, but also during the flexion observed in the weight bearing phase. Identification of possible differences in EMG activation characteristics between healthy patients and dogs with or predisposed to orthopedic and neurological disease may help understanding the neuromuscular abnormality and gait mechanics of such disorders in the future. Conformation parameters, obtained from femoral and tibial radiographs, hind limb CT images, and dual-energy X-ray absorptiometry, of hind limbs predisposed to CCL deficiency were compared with the conformation parameters from hind limbs at low risk. A combination of tibial plateau angle and femoral anteversion angle measured on radiographs was determined optimal for discriminating predisposed and non-predisposed limbs for CCL disease in Labrador Retrievers using a receiver operating characteristic curve analysis method. In the future, the tibial plateau angle (TPA) and femoral anteversion angle (FAA) may be used to screen dogs suspected of being susceptible to CCL disease. Last, kinematics and kinetics across the hock, stifle and hip joints in Labrador Retrievers presumed to be at low risk based on their radiographic TPA and FAA were compared to gait data from dogs presumed to be predisposed to CCL disease for overground and treadmill trotting gait. For overground trials, extensor moment at the hock and energy generated around the hock and stifle joints were increased in predisposed limbs compared to non predisposed limbs. For treadmill trials, dogs qualified as predisposed to CCL disease held their stifle at a greater degree of flexion, extended their hock less, and generated more energy around the stifle joints while trotting on a treadmill compared with dogs at low risk. This characterization of the gait mechanics of Labrador Retrievers at low risk or predisposed to CCL disease may help developing and monitoring preventive exercise programs to decrease gastrocnemius dominance and strengthened the hamstring muscle group.

Desenvolvimento de protótipo de aplicativo móvel em Android® para o controle e acompanhamento nutricional da saúde óssea em mulheres menopáusicas

Following a drop in estrogen in the period of menopause some women begin to lose bone mass more than 1% per year reaching the end of five years with loss greater than 25%. In this regard, factors such as older age, low calcium intake and premature menopause favor the onset of osteoporosis. Preventive methods such as nutritional counseling to a proper diet and the support of technology through applications that assess dietary intake are essential. Thus, this study aimed to develop an application for Android® platform focused on the evaluation of nutritional and organic conditions involved in bone health and risks for developing osteoporosis in postmenopausal women. To achieve this goal we proceeded to a study of 72 women aged 46-79 years, from the physical exercise for bone health of the Laboratory for Research in Biochemistry and Densitometry the Federal Technological University of Paraná program. Data were collected in the second half of 2014 through tests Bone Densitometry and Body Composition, Blood Tests, Anthropometric data and Nutrition Assessment. The study included women with a current diagnosis of osteopenia or osteoporosis primary, aged more than 45 years postmenopausal. For the assessment of bone mineral density and body composition used the device Absorptiometry Dual Energy X-ray (DXA) brand Hologic Discovery TM Model A. For anthropometric assessment was included to body mass, height, abdominal circumference, Waist circumference and hip circumference. The instrument for assessing food consumption was used Recall 24 hours a day (24HR). The estimated intake of energy and nutrients was carried from the tabulation of the food eaten in the Software Diet Pro 4®. In a sub sample of 30 women with osteopenia / osteoporosis serum calcium and alkaline phosphatase tests were performed. The results demonstrated a group of women (n = 30) average calcium intake of 570mg / day (± 340). The analysis showed a mean serum calcium within the normal range (10,20mg / dl ± 0.32) and average values and slightly increased alkaline phosphatase (105.40 U / L ± 23.70). Furthermore, there was a significant correlation between the consumption of protein and the optimal daily intake of calcium (0.375 p-value 0.05). Based on these findings, we developed an application early stage in Android® platform operating system Google®, being called OsteoNutri. We chose to use Java Eclipse® where it was executed Android® version of the project; choice of application icons and setting the visual editor for building the application layouts. The DroidDraw® was used for development of the three application GUIs. For practical tests we used a cell compatible with the version that was created (4.4 or higher). The prototype was developed in conjunction with the Group and Instrumentation Applications Development (GDAI) of the Federal Technological University of Paraná. So this application can be considered an important tool in dietary control, allowing closer control consumption of calcium and dietary proteins.

A home-based treadmill training reduced epicardial and abdominal fat in postmenopausal women with metabolic syndrome

Introduction: The current study was designed to determine the effect of home-based treadmill training on epicardial and abdominal adipose tissue in postmenopausal women with metabolic syndrome (MS). A secondary objective was to identify significant correlations between imaging and conventional anthropometric parameters. Material and methods: Sixty postmenopausal women with MS volunteered for the current trial. Thirty were randomly assigned to perform a supervised home-based 16-week treadmill training program, 3 sessions/week, consisting of a warm-up, 30-40 min treadmill exercise (increasing 5-minutes each 4-weeks) at a work intensity of 60-75% of peak heart rate (increasing 5% each 4-weeks) and cooling-down. Epicardial fat thickness (EFT) was assessed by echocardiography. Abdominal fat mass in the lumbar regions L1-L4 and L4-L5 was determined by dual X-ray absorptiometry. Results: Epicardial fat thickness and abdominal fat percentages were significantly improved after the completion of the training program. Another striking feature of the current study was the moderate correlation that was found between EFT and waist circumference (WC). Conclusion: Home-based treadmill training reduced epicardial and abdominal fat in postmenopausal women with MS. A secondary finding was that a moderate correlation was found between EFT and WC. While current investigations are promising, future studies are still required to consolidate this approach in clinical application.

Comparação de diferentes tipos de exercício na composição corporal e força em jovens desportistas do sexo feminino

O estudo pretende comparar o efeito de diferentes tipos de exercício físico na composição corporal e força em jovens desportistas do sexo feminino. A amostra foi constituída por vinte e seis desportistas femininas com idades compreendidas entre os 16 e 21 anos. Previamente ao início do estudo foram sujeitas ao 1º momento de avaliação, e após vinte e quatro semanas realizaram o segundo e ultimo momento de avaliação. Os parâmetros avaliados foram a composição corporal através da técnica de absorciometria radiológica de dupla energia; a força isocinética, nomeadamente os momentos de força (peak-torques) e rácios nos músculos extensores e flexores do joelho; a potência muscular nos membros inferiores através dos saltos verticais Squat jump e Countermovement jump. Posteriormente foram separadas em quatro grupos, grupo natação e exercício vibratório (NAT EV; n= 6), grupo natação (NAT; n=6), grupo futsal (FUTS; n= 6) e o grupo de controlo (CONT; n= 8). O grupo (NAT/EV), participou num programa de exercício vibratório (EV), três sessões por semana complementar ao treino de natação. O grupo de (NAT) cumpriu o plano de treino correspondente à disciplina, o grupo de (FUTS) cumpriu o treino referente à respetiva modalidade, o grupo controlo (CONT) realizou somente os exercícios físicos inerentes às aulas de educação física na escola. Resultados: Nas comparações inter grupos, verificou-se no grupo FUTS um aumento de 0,1 (g/m2) ± 0,0 nos valores da DMO-PE, quando comparado com o grupo de CONT, nas comparações intra grupo o grupo de NAT EV registou um acréscimo de 0,1 (g/m2) ± 0,1 nos valores da DMO-TC. Em conclusão, os resultados obtidos sugerem que a modalidade de FUTS promoveu mais alterações na composição corporal, nomeadamente na DMO-PE, no entanto dados conseguidos pelo grupo de NAT EV sugerem que o exercício vibratório poderá influenciar positivamente o incremento da DMO; ABSTRACT: The objective of this study was to compare the effect of different types of exercise on body composition and strength in young female athletes. The sample consisted of twenty-six female athletes aged between 16 and 21. Before the study there was a 1st evaluation point, after twenty-four weeks there was the 2nd and final evaluation. We evaluated body composition through x-ray absorptiometry technique of dual energy, isokinetic strength, including the peak-torques and ratios in the extensor and flexor muscles of the knee; the muscle power in the lower limbs was evaluatated through the vertical jumps Squat jump and countermovement jump. During the study they were separated into four groups, swimming exercise group and vibration (NAT EV; n = 6), swimming group (NAT; n= 6), footsal group (FUTS; n= 6) and control group (CONT; n= 8). The NAT/EV group, participated in a vibrating exercise program (EV), complementary to swimming training, with three sessions per week. The NAT group fulfilled the corresponding swimming workout plan, FUTS group fulfilled the training related to futsal, the CONT group only performed the usual exercises in physical education classes at school. Results: In intergroup comparisons, there was an increase in FUTS group of 0.1 (g / m2) ± 0.0 in the values of MBD-PE, when compared with the CONT group comparisons in intra-group group NAT EV increased by 0.1 (g / m2) ± 0.1 in BMD-TC values. In conclusion, the results suggest that FUTS group promoted more changes in body composition, particularly in BMD-PE, but data obtained by NAT EV group suggest that vibration exercise can positively influence the increase in BMD.

Influência do zinco suplementar na maturação biológica e no crescimento de jovens atletas de futebol do sexo masculino

Introdução O zinco é um importante elemento traço que auxilia na capacidade antioxidante, além de participar da maturação biológica. Em atletas, a suplementação de zinco tem efeito positivo nos parâmetros hematológicos e pode melhorar o rendimento esportivo. Sua deficiência é comumente observada nesses grupo e pode estar associada à diminuição da força física assim como da massa corporal, além de ter efeito significativo no crescimento. Assim os objetivos do presente estudo foram: comparar os métodos de avaliação da maturidade biológica e suas relações com variáveis antropométricas e de rendimento físico de acordo com o estado de zinco em jovens jogadores de futebol; comparar diferentes métodos de avaliação da composição corporal em jovens jogadores de futebol esratificados de acordo com os níveis plasmáticos de zinco e investigar o efeito do zinco suplementar na maturação biológica, no crescimento, na composição corporal e na força muscular de jogadores de futebol púberes do sexo masculino. Materiais e métodos Foram avaliados em dois momentos 48 jovens do sexo masculino (13±1 anos, massa corporal de 48±10kg, estatura de 160±10cm e zinco plasmático de 12,1±2,2 μmol/L). Todos eram jogadores de futebol de um tradicional clube do Rio de Janeiro e foram divididos aleatoriamente em dois grupos. Durante 12 semanas o grupo placebo (n=28) recebeu cápsulas de amido de milho e o grupo suplementado (n=20) recebeu cápsulas de gluconato de Zn (22mg/dia). O valor de 11,0 μmol/L foi considerado como ponto de corte para classificação dos jovens em normozincêmicos ou hipozincêmicos. No início da manhã, após jejum noturno, foram coletados sangue e urina para determinação da concentração de zinco. A massa corporal, alturas (do vértex, acromial, dactiloidal, iliocristal, trocantérica e sentado), composição corporal, força e maturidade esquelética (TW3) também foram determinadas por metodologias validadas. Resultados As comparações entre as categorias maturacionais definidas por cada método de avaliação mostraram que a idade óssea foi o único método que permitiu a identificação de diferenças entre as três categorias, em ao menos duas variáeis relacionadas ao rendimento (massa livre de gordura (MLG) e força na mão dominante (FMD) – p<0,0001). O método da pilosidade axilar foi capaz de discriminar apenas para a FMD (p<0,0001). Embora tenha fornecido quatro categorias maturacionais, o método por dosagem da testosterona não possibilitou a identificação de diferenças entre as categorias relativas a MLG, a FMD e as dobras cutâneas(DC). Quando observamos os métodos de avaliação da composição corporal não foram identificadas diferenças sigificativas entre os grupos hipozincêmico e normozincêmico no percentagem de gordura(PG) nem na MLG obtidas através dos métodos da absortometria de dupla energia (DXA) (p=0,06076 e p=0,5638 respectivamente), das DC (p=0,6840 and 0,5087) e através da bioimpedância elétrica (BIA) (p=0,3475 and p=0,3475). Entre os diferentes métodos também não foi encontrada diferenças significativas (PG: p=0,1272 e p=0,3231 - MLG: p=0,9229 and p=0,8933 para os grupos hipozincêmico e normozincêmico, respectivamente). As correlações entre os métodos foram significativas (PG: r= 0,3414 a 0,9765 e p<0,0001 a 0,0133 - MLG: r=0,9533 a 0,9998 e p<0,0001). Fortes coeficientes de determinação foram obtidos nas regressões múltiplas dos valores do DXA com a equação de Slaughter na estimativa da PG (r=0,86; r2=0,928 e SEE=2,37%) e ainda maiores para MLG (r=0,98; r2=0,990 e SEE=1,18kg). Valores menores foram encontrados para as outras equações com DC e para BIA. Ao analisar os efeitos da suplementação de zinco sobre o crescimento, a maturação, a composição corporal e a força, observou-se que somente as alterações ocorridas nos indicadores de crescimento foram significativas (p=0,0312), sendo que todas as demais não foram significativas - idade óssea (p=0,1391), massa livre de gordura (p=0,0593), percentual de massa gorda (p=0,2212) e força na mão dominante (p=0,6569). Conclusões Observando diferentes métodos de avaliação da maturidade biológica e as categorias por eles definidas, o método da idade óssea (IO) mostrou ser melhor, visto que ele permitiu identificar diferenças entre as três categorias possíveis, nas variáveis MLG e FMD, ao contrário dos outros métodos. Para a avaliação da composição corporal, os métodos baseados nas DC foram melhores que BIA, quando DXA não estiver disponível. A comparação entre os métodos baseados nas DC mostrou que a melhor associação foi obtida com a equação de Slaughter, seguida pela equação de Lohman com a utilização da IO ao invés da idade cronológica. Os níveis de zinco plasmático parecem não serem influenciados pela composição corporal, o que certamente justifica mais estudos. Os resultados da análise dos efeitos da suplementação de zinco no crescimento, na maturação, na composição corporal e na força, nos levam a concluir que o crescimento teve alteração positiva significativa e que os valores das demais variáveis estudadas (maturação, composição corporal e força muscular) não sofreram alterações significativas relacionadas à suplementação de zinco nos jovens jogadores de futebol do sexo masculino, na faixa etária dos 12 aos 14 anos.

A meta-analysis of trabecular bone score in fracture risk prediction and its relationship to FRAX

Trabecular bone score (TBS) is a grey-level textural index of bone microarchitecture derived from lumbar spine dual-energy X-ray absorptiometry (DXA) images. TBS is a BMD-independent predictor of fracture risk. The objective of this meta-analysis was to determine whether TBS predicted fracture risk independently of FRAX probability and to examine their combined performance by adjusting the FRAX probability for TBS. We utilized individual level data from 17,809 men and women in 14 prospective population-based cohorts. Baseline evaluation included TBS and the FRAX risk variables and outcomes during follow up (mean 6.7 years) comprised major osteoporotic fractures. The association between TBS, FRAX probabilities and the risk of fracture was examined using an extension of the Poisson regression model in each cohort and for each sex and expressed as the gradient of risk (GR; hazard ratio per 1SD change in risk variable in direction of increased risk). FRAX probabilities were adjusted for TBS using an adjustment factor derived from an independent cohort (the Manitoba Bone Density Cohort). Overall, the GR of TBS for major osteoporotic fracture was 1.44 (95% CI: 1.35-1.53) when adjusted for age and time since baseline and was similar in men and women (p > 0.10). When additionally adjusted for FRAX 10-year probability of major osteoporotic fracture, TBS remained a significant, independent predictor for fracture (GR 1.32, 95%CI: 1.24-1.41). The adjustment of FRAX probability for TBS resulted in a small increase in the GR (1.76, 95%CI: 1.65, 1.87 vs. 1.70, 95%CI: 1.60-1.81). A smaller change in GR for hip fracture was observed (FRAX hip fracture probability GR 2.25 vs. 2.22). TBS is a significant predictor of fracture risk independently of FRAX. The findings support the use of TBS as a potential adjustment for FRAX probability, though the impact of the adjustment remains to be determined in the context of clinical assessment guidelines.