A. González-Agüero

Effects of Training on Bone Mass in Older Adults A Systematic Review

It is widely recognized that the risk of fractures is closely related to the typical decline in bone mass during the ageing process in both women and men. Exercise has been reported as one of the best non-pharmacological ways to improve bone mass throughout life. However, not all exercise regimens have the same positive effects on bone mass, and the studies that have evaluated the role of exercise programmes on bone-related variables in elderly people have obtained inconclusive results. This systematic review aims to summarize and update present knowledge about the effects of different types of training programmes on bone mass in older adults and elderly people as a starting point for developing future interventions that maintain a healthy bone mass and higher quality of life in people throughout their lifetime.A literature search using MEDLINE and the Cochrane Central Register of Controlled Trials databases was conducted and bibliographies for studies discussing the effect of exercise interventions in older adults published up to August 2011 were examined. Inclusion criteria were met by 59 controlled trials, 7 meta-analyses and 8 reviews. The studies included in this review indicate that bone-related variables can be increased, or at least the common decline in bone mass during ageing attenuated, through following specific training programmes. Walking provides a modest increase in the loads on the skeleton above gravity and, therefore, this type of exercise has proved to be less effective in osteoporosis prevention. Strength exercise seems to be a powerful stimulus to improve and maintain bone mass during the ageing process. Multi-component exercise programmes of strength, aerobic, high impact and/ or weight-bearing training, as well as whole-body vibration (WBV) alone or in combination with exercise, may help to increase or at least prevent decline in bone mass with ageing, especially in postmenopausal women. This review provides, therefore, an overview of intervention studies involving training and bone measurements among older adults, especially postmenopausal women. Some novelties are that WBV training is a promising alternative to prevent bone fractures and osteoporosis. Because this type of exercise under prescription is potentially safe, it may be considered as a low impact alternative to current methods combating bone deterioration. In other respects, the ability of peripheral quantitative computed tomography (pQCT) to assess bone strength and geometric properties may prove advantageous in evaluating the effects of training on bone health. As a result of changes in bone mass becoming evident by pQCT even when dual energy X-ray absortiometry (DXA) measurements were unremarkable, pQCT may provide new knowledge about the effects of exercise on bone that could not be elucidated by DXA. Future research is recommended including longest-term exercise training programmes, the addition of pQCT measurements to DXA scanners and more trials among men, including older participants.

Health-related physical fitness in children and adolescents with Down syndrome and response to training

Physical fitness is related to health at all ages. Information about physical fitness in the Down syndrome (DS) population, however, is scarce, especially when we consider children and adolescents. A review of the current data available on this topic would be both timely and important as it would serve as a starting point to stimulate new research perspectives. The data we reviewed from the literature showed a general trend toward lower values of physical fitness parameters and worse body composition variables in children and adolescents with DS compared with the population without intellectual disability (ID) or even with the population with ID without DS. Notably, children and adolescents with DS have been described as less active or overprotected; however, these factors may not be the cause of their poor physical fitness. Many of the training programs carried out in children and adolescents with DS did not yield the desired responses, and the reasons are still unknown. The purpose of this review is to summarize the current available literature on health‐related physical fitness in children and adolescents with DS, and the effect of training on these variables. From the literature available, it is clear that more data on this population are necessary.

Impact of methodological decisions on accelerometer outcome variables in young children

Background:The impact of accelerometer-related methodological decisions relating to the assessment of physical activity and sedentary time has not been conclusively determined in young children.Objectives:To determine the effects of epoch and cutoff points on the assessment of physical activity and sedentary time and to determine the accelerometer wear time required to achieve reliable accelerometer data in children.Design:Children were recruited from centres at Ghent, Glasgow, Gothenburg and Zaragoza.Methods:Physical activity was assessed for 1 week in 86 children (41 girls, 45 boys; mean age 7±2 years) by uniaxial accelerometry. The epoch was set at 15 s and reintegrated to 30 and 60 s. Time spent sedentary and in moderate and vigorous physical activity (MVPA) was assessed using a range of cutoff points. Number of days required to achieve 80% reliability was predicted using the Spearman–Brown Prophecy formula.Results:The Reilly cutoff points (<1100 counts per min (CPM)) indicated less sedentary time per day when comparing 15 vs 30 s and 15 vs 60 s epochs: 570±91 vs 579±93 min and 570±91 vs 579±94 min, respectively; P<0.05. Pate cutoff points (>420 counts per 15 s) reported more MVPA time per day compared with Sirard (890 counts per 15 s) and Puyau cutoff points (>3200 counts per min) using 15 s epoch: 78 (4–197) min (median (range) vs 18 (1–80) min and 24 (1–100) min, respectively; P<0.001. Compliance with guidelines of at least 60 min MVPA was 84, 78 and 73% for Pate cutoff points using 15, 30 and 60 s epochs, respectively, but 0% for Sirard and Puyau cutoff points across epochs. The number of days required to achieve 80% reliability for CPM, sedentary and MVPA time was 7.4–8.5 days.Conclusion:Choice of epoch and cutoff point significantly influenced the classification of sedentary and MVPA time and observed compliance to the MVPA guidelines.

Bone mass in male and female children and adolescents with Down syndrome

SummaryChildren and adolescents with Down syndrome (DS) have lower levels of bone mass compared with youths without DS. Their sexual dimorphism in bone mass also differs from that observed in children and adolescents without Down syndrome.IntroductionThis study aimed to compare bone mass and sexual dimorphism in bone mass between male and female youths with DS and age- and sex-matched controls without DS.MethodsBone mineral density (BMD), volumetric BMD, bone mineral apparent density (BMAD), BMD/height (BMDH), and total lean mass were measured or calculated from DXA. Thirty-two youths (15 females) with DS and 32 youths (13 females) without DS participated in the study.ResultsANOVA tests showed lower BMAD and BMDH in females with DS compared with females without DS. ANCOVA tests revealed lower BMD in the whole body of males and females as well as BMD in the hip region of the females with DS compared with their counterparts without DS. Within the group with DS, females had greater lumbar spine BMD than the males.ConclusionsThe low values of BMD and related parameters, together with the differences in the sexual dimorphism, indicate a non-standard bone development in this specific population of children and adolescents with DS.

Accuracy of prediction equations to assess percentage of body fat in children and adolescents with Down syndrome compared to air displacement plethysmography

To determine the accuracy of the published percentage body fat (%BF) prediction equations (Durnin et al., Johnston et al., Brook and Slaughter et al.) from skinfold thickness compared to air displacement plethysmography (ADP) in children and adolescents with Down syndrome (DS). Twenty-eight children and adolescents with DS (10-20 years old; 12 girls, 16 boys) participated in the study. Anthropometric measurements height, weight, and skinfolds biceps, triceps, subscapular and suprailiac were performed following ISAK recommendations. Total body density (TBD) was estimated using three equations and was also measured with ADP; while %BF was calculated from all densities using the Siri equation and from skinfolds using the Slaughter et al. equation. Finally, the agreement between methods was assessed by plotting the results in Bland-Altman graphs. The presence of heteroscedasticity was also examined. Despite the equation of Slaughter et al. had a large 95% limits of agreement, it was the only one without a significant inter-methods difference and without heteroscedasticity. The equation of Slaughter seems to be, from the studied, the most accurate for estimating %BF in children and adolescents with DS.

Effects of a short-term whole body vibration intervention on physical fitness in elderly people

We aimed to clarify whether a short-term whole body vibration (WBV) training has a beneficial effect on physical fitness in elderly people. Forty-nine non-institutionalized elderly (75.0 ± 4.7 years) participated in the study. Twenty-four of them trained on a vibration platform for 11 weeks. Physical fitness included balance, lower- and upper-body strength and flexibility, agility, walking speed and endurance. In the WBV group most of the physical tests improved through the intervention (all P < 0.01) while in the control group only an increment was detected in lower-body strength (P < 0.05). In conclusion, a short-term WBV training is beneficial for physical fitness among elderly people.

Swimming training repercussion on metabolic and structural bone development; benefits of the incorporation of whole body vibration or pilometric training; the RENACIMIENTO project

INTRODUCTION Enviromental factors such as exercise participation and nutrition have often been linked to bone improvements. However, not all sports have the same effects, being non-osteogenic sports such as swimming defined as negative or neutral sports to practice regarding bone mass by some authors, similarly exercise-diet interaction in especific groups is still not clear. OBJECTIVE To present the methodology of the RENACIMENTO project that aims to evaluate body composition and more specifically bone mass by several techniques in adolescent swimmers and to observe the effects and perdurability of whole body vibration (WBV) and jumping intervention (JIN) on body composition and fitness on this population and explore posible diet interactions. DESIGN Randomized controlled trial. METHODS 78 swimmers (12-17 y) and 26 sex- and age-matched controls will participate in this study. Dual energy X-ray, peripheral Quantitative Computed Tomography, Quantitative Ultrasound, Bioelectrical Impedance Analysis, and anthropometry measurements will be performed in order to evaluate body composition. Physical activity, nutrition, pubertal development and socio-economical status may act as confounders of body composition and therefore will also be registered. Several fitness factors regarding strength, endurance, performance and others will also be registered to evaluate differences with controls and act as confounders. A 7-month WBV therapy will be performed by 26 swimmers consisting of a training of 15 minutes 3 times per week. An 8 month JIM will also be performed by 26 swimmers 3 times per week. The remaining 26 swimmers will continue their normal swimming training. Four evaluations will be performed, the first one in order to describe differences between swimmers and controls. The second one to describe the effects of the interventions and the third and fourth evaluations to describe the perdurability of the effects of the WBV and JIN. CONCLUSION The RENACIMIENTO project will allow to answer several questions regarding body composition, fitness, bone mass and interaction with diet of adolescent swimmers, describe swimming as a positive, negative or neutral sport to practice regarding these parameters and elucidate the effects and perdurability of WBV and JIM on body composition.

DO CALCIUM AND VITAMIN D INTAKE INFLUENCE THE EFFECT OF CYCLING ON BONE MASS THROUGH ADOLESCENCE

INTRODUCTION Cycling has been associated with decreased bone mass during adolescence. Calcium (Ca) and vitamin D (VitD) intake are associated to bone mass and may be important confounders when studying bone mass. AIM To clarify the effect that Ca and VitD may have on bone mass in adolescent cyclists. METHODS Bone mineral content (BMC) and density (BMD) of 39 male adolescents (20 cyclists) were measured. Ca and VitD intake were also registered. Different ANCOVA analyses were performed in order to evaluate the influence of Ca and VitD on BMC and BMD. RESULTS Cyclists showed lower values of BMC and BMD than controls at several sites and when adjusting by Ca, Wards triangle BMD appeared also to be lower in cyclists than controls. CONCLUSION Nutritional aspects might partially explain differences regarding bone mass in adolescent cyclists and should be taken into account in bone mass analysis as important confounders.

The nutritional status in adolescent Spanish cyclists

INTRODUCTION Adolescence is an important period of nutritional vulnerability due to the increased dietary requirements. OBJECTIVE To describe the nutritional status of adolescent cyclist and a group of normoactive controls. METHODS The HELENA Dietary Assessment Tool was used to evaluate the nutritional intake of 20 adolescent cyclists and 17 controls. Total energy intake, resting energy expenditure (REE), total energy expenditure (TEE), macronutrients and several micronutrients were registered and compared with dietary guidelines. RESULTS REE was lower and TEE higher in cyclists than in controls (both P < 0.01). Significant differences were observed in phosphorus and vitamin B1 being higher in cyclists (P < 0.05). Most participants, both cyclist and controls, did not reach the diet requirements for macronutrients, vitamins and minerals. CONCLUSION Nutritional status of adolescent cyclists and controls seems not to fulfil the requirements in quantity and quality. Possible implications for actual and future health especially in athlete adolescents need further research.

Body Composition in Spanish Soccer Referees

The aim of this study was to examine body fat of elite Spanish soccer referees and assistant referees by division, role and age group. Participants were 243 males (age 32.4 ± 5.3 years, weight 72.3 ± 6.2 kg, height 179.1 ± 5.9 cm and body mass index 22.5 ± 1.4) who belonged to the Referees Technical Committee of the Royal Spanish Soccer Federation. A portable bioelectrical impedance analyser TANITA BC 418-MA was used to estimate the percentage of body fat (%BF). In the first analysis, they were classified by division and role: 158 elite Spanish league referees (n = 20 first-division referees; n = 22 second-division referees and n = 116 second-B-division referees) and 85 elite Spanish league assistant referees (n = 40 first-division assistant referees and n = 45 second-division assistant referees). In the second analysis, they were divided into three age groups as previously described by Castagna: young (Y, 27–32 years, n = 144), average (A, 33–38 years, n = 66) and senior (S, 39–45 years, n = 33). Analysing by division and role, the first-division referees were the oldest and the second-B-division referees were the youngest. First- and second-B-division referees had lower total %BF than first- and second-division assistant referees (9.6% and 9.8% vs 12.8% and 12.0%, p < 0.05). Comparing by age group, Y group had lower %BF than A and S groups (10.2% vs 11.4% and 12%, p < 0.05), but no differences were found between A and S groups. These results showed that first- and second-B-division referees presented more healthy values of %BF than first- and second-division assistants. By age group, Y group had the lowest %BF.