Speed, agility, and musculoskeletal fitness are independently associated with areal bone mineral density in children

Background: There is still little understanding of the associations between physical fitness variables and bone health in children taking into account key confounders. Aim: The aim of this study was to analyze the associations between performance in tests of speed, agility, and musculoskeletal fitness (power of the upper and lower limbs) with bone mass of different regions in children, considering the adjustment to maturity-offset, lean percentage, and sex. Methods: Cross-sectional study design: the sample consisted of 160 children aged 6–11 years. The physical fitness variables tested were 1) speed, assessed with the running test at a maximum speed of 20 m; 2) agility, assessed through the 4×4-m square test; 3) lower limb power, assessed using the standing long jump test, and 4) upper limb power, assessed using the 2-kg medicine ball throw test. Areal bone mineral density (aBMD) was obtained from the analysis of body composition by dualenergy X-ray absorptiometry (DXA). Simple and multiple linear regression models were performed using the SPSS software. Results: In the crude regression analyses, the results indicated a linear relationship between all the physical fitness variables and aBMD in all body segments, but maturity-offset, sex, and lean mass percentage seemed to have an effect on these relationships. Except for the upper limb power, the other physical capacities (speed, agility, and lower limb power) were associated with aBMD in at least three body regions in the adjusted analyses. These associations occurred in the spine, hip, and leg regions, and the aBMD of the legs presented the best association magnitude (R2 ). Conclusion: There is a significant association between speed, agility, and musculoskeletal fitness, specifically the lower limb power and aBMD. That is, the aBMD is a good indicator of the relationship between fitness and bone mass in children, but it is essential to consider specific fitness variables and skeletal regions

Demographic, socioeconomic, dietary and physical activity determinants of obesity in a large nationally representative sample of the Lebanese adult population.

Introduction: The prevalence of obesity within countries varies by gender, age, socioeconomic status, and culture. These determinants appear to predict obesity differently in different countries. The objective of this study was to estimate the impact of these determinants on obesity in a representative sample of the Lebanese adult population. Methods: A cross-sectional survey of 2697 adults aged ≥ 20 years, excluding pregnant and lactating women, was conducted in 2008. Households were selected randomly from all Governates of Lebanon based on a stratified cluster sampling. One randomly-sampled adult was interviewed in each visited household; demographic, socioeconomic and anthropometric data were measured. Dietary intake was obtained using a 24-hour recall instrument. The prevalence of obesity in 2008 was estimated. Logistic regressions analysis was carried out to assess the relationship between energy intake and obesity as well as adjusted relevant variables, excluding data from participants who reported implausible energy intakes. Results: Currently, approximately one in four Lebanese adults is obese. While men and women showed overall similar prevalence rates of obesity, gender disparities were noted across obesity classes and age groups. In males, the odds of being obese increased among those married, employed, and owning increased household assets; the opposite was the case for women. Obesity in women decreased with increasing household wealth. In women also, there was a positive association between obesity and energy intake, and a negative association between obesity and physical activity. Obese adults reported consuming a higher percentage of their energy intake from fat, and a lower intake from cereals, compared with their non-obese counterparts. Conclusion: The prevalence of obesity among Lebanese adults is on the rise, with significant demographic and socioeconomic differentials. High energy consumption and inactivity of Lebanese adults, as well as several complex socioeconomic and cultural elements, are contributing factors to the estimated high rates of obesity

The impact of different loading sports and a jumping intervention on bone health in adolescent males

Adolescence is a crucial period for bone development and exercise can enhance bone acquisition during this period of life. However, there is a lack of scientific evidence on how different loading sports practiced during adolescence can affect bone development in males. The present thesis is part of the PRO-BONE study and aimed to investigate the cross-sectional and longitudinal effects of participation in football (osteogenic sport), swimming and cycling (non-osteogenic sports) on bone mass, bone geometry, texture and bone metabolism in adolescent males. An active control group has been included too. Additionally, the thesis examined the effect of a 9-month jumping intervention programme on bone outcomes in adolescent males involved these sports. Cross-sectional findings from Chapter 4 show that footballers have better bone status than swimmers, cyclists and controls (7 to 21 %), and that there are no differences between participants of non-osteogenic sports and controls. Chapter 5 identifies that lean mass is the strongest determinant of bone outcomes, followed by football participation and height in adolescent male athletes, whereas the contribution of the other predictors, such as nutrition, physical activity and fitness, is site specific. Longitudinal evidence in Chapters 6 and 7 show that bone mass (5 to 8 %) and geometry (4 to 10 %) is higher in adolescent male footballers compared to swimmers and cyclists after one year of sport specific training, and that there are no differences in bone development between non-osteogenic sports groups and controls. Chapters 8 and 9 indicate that a 9-month jumping intervention programme can improve bone outcomes only in male adolescents participating in swimming and cycling (4 to 13 %), but not in those engaged in football, while it can improve fitness outcomes in all 4 groups (4 to 8 %). Collectively, the present thesis contributes to the literature by providing novel evidence in adolescent male athletes on the effects of popular sports such as football, swimming and cycling on bone status and development, and that a jumping intervention programme can improve bone development in those involved in non-osteogenic sports.European Commission: This project is funded by the European Union Seventh Framework Programme ([FP7/2007-2013]

Material Clues: decoding our past to understand our present

Buildings are melting pots of stories and experiences. They are not just a manmade product but also a container of memory. The submitted image shows the side of a building lining a narrow street in Barcelona. It shows physical (material) evidence of a door once being within the stone wall. What was this door used for? What were the aspirations behind the removal of this door? We can ask these questions and ponder their answers because clues have been left within the building materiality –a brick door infill, set within a stone wall; a timber lintel left in-situ, relieved of its only duty. When trying to answer the above questions, we realise that understanding buildings is not about architecture - it is about people. The more we understand these changes, the more we connect with those who came before us, clarifying who we are and what we are building upon

Zinc intake, zinc status and expression of zinc transporter genes in younger and older Saudi adults

PhD ThesisBackground: During ageing, there are changes in many physiological systems including the gastrointestinal tract which may result in decreased absorption of micronutrients such as zinc. Decreased dietary absorption efficiency and/or inadequate zinc intake are contributing factors to the decline in plasma zinc concentration that has been reported in older adults. This decline in plasma zinc concentration may have important implications for health, e.g. through reduced immune function. To date, there is limited information on the relationships between zinc intake and plasma zinc concentration during ageing among adults in Saudi Arabia or on the molecular mechanisms responsible for age-related effects. Thus, the aims of this study were to test the hypothesis that changes in expression of zinc transporters including ZnT1, ZnT5 and ZIP4 are associated with changes in zinc status in young and older Saudi adults. Methods: Two hundred and two young and older Saudi adults of both sexes were recruited from Jeddah city in the western region of Saudi Arabia. Intakes of zinc and of zinc absorption modifiers in diet were assessed using an FFQ (designed and validated for this purpose) while plasma zinc concentration was determined by ICP-OES. RNA was extracted from white blood cells and qPCR was used to quantitatively measure expression of the ZnT1, ZnT5 and ZIP4 genes at the mRNA level. Results: Intakes of zinc and of protein were significantly higher in males than in females (P<0.05). A substantial proportion of the participants appeared to have inadequate zinc intake with the risk of inadequacy being greatest for young males (15%) and young females (4%). Plasma zinc concentrations in older adults were significantly higher than in young adults (P<0.05). Older males had significantly higher ZIP4 expression compared with young adults (P<0.05). Although older adults had apparently higher ZnT1 and ZnT5 expression than young adults, these differences were statistically non-significant. Several age and sex-specific correlations between zinc intake, zinc status and expression of zinc transporters were observed. Young and older adults who had apple-shaped fat distribution pattern, had significantly higher expression of ZnT1, ZnT5 and ZIP4 and plasma zinc status compared with participants who had pear-shaped fat distribution pattern (P<0.05). Discussion: Despite the changes in food availability in Saudi Arabia over recent decades, the prevalence of low zinc intake remains substantial. Contrary to reports from elsewhere, the prevalence of low plasma II zinc concentrations was greater in younger than in older Saudi adults. This study also identified relationships between expression of zinc transporters and zinc intake, zinc status and abdominal fatness in Saudi adults

Metabolically Healthy Obesity

Accumulating evidence suggests that not all obese subjects are at increased cardiometabolic risk and that the “metabolically healthy obese” phenotype may exist in the absence of metabolic abnormalities. Limited data regards the determinants of metabolically healthy obesity exist, particularly in relation to genetics, dietary and lifestyle behaviours. In light of the current obesity epidemic, it is clear that current “one size fits all” approaches to tackle obesity are largely unsuccessful. Whether dietary, lifestyle and/or therapeutic interventions, based on stratification of obese individuals according to their metabolic health phenotype, are more effective remains to be seen, with limited and conflicting data available. This book includes original research articles and reviews of the scientific literature that contribute to our understanding of the role of clinical, biological, genetic, and environmental factors in metabolically healthy and unhealthy obesity

Профил физичке активности, навика у исхрани и телесне композиције код студената либанских универзитета: упоредна студија

Introduction: High school students’ weight gain is observable in the period of their transition from school to university. In universities, students encounter several challenges in adopting a new lifestyle due to study stress, time management problems, busy class schedules and other challenges. All these chellenges make those students unaware about their health. During this transition period of life, university students are vulnerable to unhealthy eating patters and sedentary lifestyle behaviors such as fast food snacking, meal skipping, excessive smoking and alcohol consumption, excessive internet use as well as inactivity. These unhealthy lifestyle behaviors comprised of sedentary behaviors including low level of physical activity, sitting for long hours of study, combined with unhealthy eating habits like fast food snacking, meal skipping, low consumption of fruits and vegetables, low intake of dietary products, are associated with weight gain and obesity in this critical life age. Therefore, these worrisome unhealthy lifestyle behaviors calls for appropriate lifestyle changes before disease development and morbidity. Purpose: The purpose of the study is to examine the relationships between the two most important factors of quality of life, such as physical activity and dietary (eating) habits, and to determine their impact on body composition, and all in relation to student specialty and gender characteristics among Lebanese universities’ students. Methods: The studied sample included 384 Lebanese student from the Lebanese University, Faculty of Education. These students were divided into 4 subsamples for the purpose of this dissertation, 100 sport male student, 100 sport female students, 70 non- sport male students, and 114 non-sport female students. The three-lifestyle factors: Physical Activity, Dietary habits, and Body composition were identified and assessed. Physical Activity was assessed using the self-administered extended form English version of IPAQ (International Physical Activity Questionnaire) containing 27 questions that covers four (4) domains of physical activity (work-related physical activity, transport-related physical activity, domestic (housework) and gardening (yard) activities, leisure time physical activity), along with the time spent sitting. All questions refer to the previous 7 days. As for Nutrition habits, the standardized Dietary questionnaire was used including four sections: Eating Habits, Physical Activity, Dietary Beliefs, and Nutrition Knowledge. Body Composition was assessed using the method of multifrequency bioelectrical analysis. A multi-channel bioelectric impedance analyzer InBody 270 (Biospace Co. Ltd, Seoul, Korea) was utilized to measure sets of five primary direct measures of body composition variables (BM, BH, BFM, SMM, TBW) and seven derived indirect measures (BMI, PBFM, BFMI, PSMM, SMMI, IH, MFI). Results: Starting with body composition, all Lebanese students’ samples were found in normal body weight except the non-sport male students which were found overweight.вод: Прелазак из средње школе на колеџ или универзитет је критичан период за повећање телесне масе. Млади одрасли на универзитетима се генерално суочавају са различитим изазовима као што су усвајање новог окружења, стрес од учења, недостатак правилног управљања временом и интензиван распоред часова који доводе до недостатка свести о свом здрављу. Током овог периода живота, студенти практикују неке нездраве навике у исхрани и стилове живота као што су прескакање оброка, једење грицкалица, конзумација брзе хране, пушење, прекомерна употреба интернета, физичка неактивност и седентарно понашање. Низак ниво физичке активности (ФA) у комбинацији са седентарним понашањем (нпр. гледање телевизије, седење уз рачунар) такође је повезан са повећањем телесне масе и гојазношћу. Нездраве дијететске навике међу студентима, као што су избегавање оброка, мала конзумација воћа и поврћа, висок унос брзе хране и низак унос млечних производа забрињавају и појачавају потребу за раним откривањем нездравих навика у исхрани, тако да се могу направити одговарајуће промене начина живота пре као превентива могућих здравствених поремећаја. Циљ: Циљ рада је да се испитају односи између два најважнија фактора квалитета живота, као што су физичка активност и навике у исхрани, и да се утврди њихов утицај на телесну композицију, а све у вези са врстом студија и родним карактеристикама студената либанских универзитета. Методе: Проучавани узорак обухватао је 384 либанска студента са Педагошког факултета Универзитета у Либану. Ови студенти су за потребе ове дисертације подељени у 4 подузорка, 100 студената спорта, 100 студенткиња спорта, 70 студената који се не баве спортом и 114 студенткиња неспортиста. Идентификовани су и процењена три фактора начина живота: физичка активност, навике у исхрани и композиција тела. Физичка активност је процењена коришћењем проширене енглеске верзије IPAQ (Интернационални Упитик о Физичкој Активности) која садржи 27 питања која покривају четири (4) домена физичке активности (физичка активност у вези са радом, физичка активност везана за транспорт, кућни послови и баштенске тј. дворишне активности, физичка активност у слободно време), као и време проведено седећи. Сва питања су се односила на претходних 7 дана. Што се тиче навика у исхрани, коришћен је стандардизован упитник о исхрани који укључује четири одељка: навике у исхрани, физичка активност, уверења о исхрани и знање о исхрани..

VITAMIN D STATUS IN RELATION TO DIETARY INTAKE, SUN EXPOSURE OBESITY, LIFESTYLE FACTORS AND BONE HEALTH AMONG SAUDI PREMENPOUSAL WOMEN LIVING IN JEDDAH CITY

Saudi women are at risk of vitamin D deficiency and low bone mass because traditional clothing and time spent indoors limit sun exposure. However, no information about other contributing individual, demographic, and cultural risk factors which may determine women’s vitamin D status is available. Moreover, little is known about vitamin D intake, and the association between vitamin D and calcium intake and bone mineral density (BMD) in premenopausal Saudi women. The objectives of the study were to identify predictors strongly associated with vitamin D deficiency, identify dietary vitamin D sources, examine potential determinants of vitamin D intake, examine the association of vitamin D and calcium intake with BMD, and explore how the relationship between knowledge of vitamin D and attitudes about sun exposure are related to serum vitamin D levels. This cross-sectional study was conducted in 257 women 20–50 years of age in Jeddah, Saudi Arabia, between December 2014 and April 2015. Data were obtained through pre-tested questionnaires. Serum 25(OH) D and serum parathyroid hormone (PTH) were measured. BMD was measured using double-energy X-ray absorptiometry in 102 participants. The prevalence of vitamin D deficiency was 77.6% (25(OH) D < 50 nmol/L). Vitamin D deficiency is associated with increased risk of elevated PTH levels. In the multiple regression analysis, serum 25(OH) D was not associated with body mass index or waist circumference. Predictors of vitamin D deficiency were low dietary and supplement vitamin D intake and younger age, explaining 41% of the variation in 25(OH) D serum concentrations (p < 0.001). Approximately 65% of the participants had vitamin D intakes below the U.S. Estimated Average Requirement (EAR) for vitamin D, and 61% fell below the EAR for calcium. Dairy products and supplements contributed the most to vitamin D intake. Older age was an independent determinant of sufficient vitamin D intake (p < 0.001). The prevalence of osteopenia was 33% in the lumbar spine and 30% in the femur neck. Education was a significant predictor of vitamin D knowledge (p < 0.001). Public health interventions offering early screenings of vitamin D status and improved nutrition in young Saudi women are recommended

Whole body vibration training in chronic disease: muscle, bone, function.

Muscle pull from regular physical activity is crucial for optimal development of the skeleton during growth and maintenance of bone mineral density (BMD) throughout life. Mitochondrial Respiratory Chain Disorders (MRCD) and Cystic Fibrosis (CF) are two chronic diseases that exhibit reduced lean tissue mass and impaired exercise capacity, which negatively impacts bone health in these populations. Whole body vibration training (WBVT) is an emerging therapeutic modality that has been successful in improving BMD and muscle mass and function in heath and disease. Aim: To evaluate whether 6 months of home-based WBVT improves BMD, muscle function, exercise capacity and quality of life (QoL) in people with MRCD or CF. Methods: Participants were enrolled for 15-18 months: 3-6 months observation; 6 months home-based WBVT (3 x 3mins daily at 20Hz on a Galileo® Home vibration platform); 6 months follow-up. Participants attended four study visits and completed: dual energy x-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) to assess BMD; muscle function testing on the Leonardo Jumping Platform (LJP); 6-minute walk test (6MWT) and/or formal exercise testing to assess exercise capacity; and disease specific QoL questionnaires. Linear mixed models analysis was used to assess changes between visits. Results: The MRCD cohort had 23 participants (13 male) mean (SD) age 31.0 (19.8) years and the CF cohort, 16 participants (8 male) mean (SD) age 12.8 (3.5) years. Statistically significant improvements in BMD of the legs were seen in the MRCD and CF cohorts for both DXA and pQCT. Muscle force during hopping and co-ordination during the chair rise test on the LJP improved significantly post WBVT in the CF. Exercise capacity did not change in the MRCD or CF cohorts after WBVT. QoL showed improvements in both cohorts. Conclusions: WBVT was well tolerated. WBVT improved BMD, aspects of muscle function, and QoL in people with MRCD or CF and may be a useful adjunct to physiotherapy exercise programs

Aptidão física relacionada à saúde de crianças : uma proposta para a identificação do risco de baixa massa óssea a partir de testes físicos

Os objetivos desta tese são: 1) verificar as associações entre o desempenho nos testes de velocidade, agilidade e potência de membros superiores e inferiores e indicadores de saúde óssea em crianças; 2) propor pontos de corte para o desempenho nos testes de aptidão física para a identificação do estado de saúde óssea de crianças; e 3) descrever o perfil da aptidão física relacionada à saúde da população infantil brasileira, considerando a inclusão dos testes de aptidão física e pontos de corte propostos. Para os objetivos 1 e 2 foram avaliadas as variáveis: velocidade a partir do teste de corrida de 20m, agilidade a partir do teste do quadrado de 4x4m, potência de membros superiores a partir do teste de arremesso de medicine ball e potência de membros inferiores a partir do teste de salto horizontal. As variáveis desfecho do estudo foram o conteúdo e a densidade mineral óssea de diferentes segmentos corporais, avaliados por exame de absorciometria por raios-X com dupla energia. O estudo realizado se caracterizou como transversal com método correlacional. Foi realizada uma análise secundária em um banco de dados com 160 crianças com idade entre seis e 11 anos de uma escola pública. Para as análises de associação foram utilizadas equações de regressão linear e para a proposição dos pontos de corte foram realizadas equações de curvas ROC. Para as quatro capacidades físicas testadas, sempre houve associações com pelo menos um segmento corporal, seja no conteúdo ou na densidade mineral óssea. Os resultados das associações ajustadas para o sexo, idade, maturação somática e percentual de gordura indicam uma relação linear entre a velocidade e o conteúdo e a densidade mineral óssea em todos os segmentos corporais. Houve uma relação linear da agilidade com o conteúdo mineral ósseo das pernas e a densidade mineral óssea do corpo todo e das pernas. Tanto a potência de membros superiores quanto a de membros inferiores se associaram apenas com o conteúdo mineral ósseo das pernas. Os valores de área sob a curva ROC nos testes do quadrado de 4x4m e salto horizontal não foram suficientes para a identificação dos pontos de corte. Já os testes de corrida de 20m, para a estimativa da velocidade e arremesso de medicine ball de 2kg para a estimativa de potência de membros superiores apresentaram acurácia suficiente para a identificação de pontos de corte para a triagem de crianças com maiores chances de possuir baixa densidade mineral óssea na coluna e na pelve. Para o objetivo 3 foi realizado um estudo independente a partir dos resultados encontrados na pesquisa. Um estudo de tendência da aptidão física relacionada à saúde de crianças brasileiras na última década foi realizado com o banco de dados do Projeto Esporte Brasil. Para esse estudo foram consideradas as variáveis índice de massa corporal, aptidão cardiorrespiratória, flexibilidade e força/resistência abdominal – que já faziam parte da aptidão física relacionada à saúde – além da velocidade e potência de membros superiores, que compõem a nova proposta. Os resultados desse estudo demonstram que todas as variáveis apresentaram uma tendência semelhante ao longo da década, apresentando um aumento considerável no percentual de crianças em zona de risco à saúde. A partir dos resultados apresentados, assim como de sua aplicabilidade demonstrada, proponho considerar como aptidão física relacionada à saúde de crianças, o conjunto de capacidades físicas: flexibilidade, capacidade cardiovascular, força muscular localizada, velocidade e potência muscular de membros superiores, agregadas à composição corporal ou indicadores antropométricos de estimativas de excesso de peso.The aims of this thesis are: 1) to verify the associations between performance in speed, agility and power of upper and lower limbs tests and children’s bone health indicators; 2) to propose cut-off points for the performance in physical fitness tests to identify the children’s bone health; and 3) to describe the profile of health-related fitness of Brazilian children, considering the inclusion of the proposed physical fitness tests and cut-off points. For aims, 1 and 2 the variables were evaluated: speed from the 20m running test, agility from the 4x4m square test, upper limb power from the medicine ball throw test and lower limb power from the horizontal jump test. The outcome variables were the bone mineral content and density of different body segments, assessed by dual energy X-ray absorptiometry. The study carried out was characterized as cross-sectional with a correlational method. A secondary analysis was carried out on a database with 160 children aged between 6- 11 years from a public school. For the association analysis, linear regression equations were used and for the proposition of the cut-off points, equations of ROC curves were performed. For the four physical abilities tested, there were always associations with at least one body segment, whether in bone mineral content or density. The results of associations adjusted for sex, age, somatic maturation and fat percentage indicate a linear relationship between speed and bone mineral content and density in all body segments. There was a linear relationship between agility and bone mineral content in the legs and bone mineral density in the total body and legs. Both the power of the upper and lower limbs was associated only with the legs’ bone mineral content. The area values under the ROC curve in the 4x4m square and horizontal jump tests were not sufficient to identify the cut-off points. The 20m running tests, for estimating the speed and throwing of 2kg medicine ball for estimating the power of upper limbs, were sufficiently accurate to identify cut-off points for screening children with greater chances of having a low bone mineral density in the spine and pelvis. For aim 3, an independent study was conducted based on the results found in the research. A trend study of health-related fitness to the Brazilian children in the last decade was carried out with the database of Projeto Esporte Brasil. For this study, the variables body mass index, cardiorespiratory fitness, flexibility and abdominal strength - which were already part of health-related fitness - were considered, in addition to the speed and power of upper limbs, which make up the new proposal. The results of this study demonstrate that all variables showed a similar trend over the decade, with a considerable increase in the percentage of children in risk to health. From the results presented, as well as its demonstrated applicability, I propose to consider as a children's health-related fitness the set of physical capacities: flexibility, cardiovascular capacity, localized muscular strength, speed and muscular power of upper limbs, added to the composition body weight or anthropometric indicators of overweight estimates