Physical activity during life course and bone mass: a systematic review of methods and findings from cohort studies with young adults

High-Protein Diets during either Resistance or Concurrent Training Have No Detrimental Effect on Bone Parameters in Resistance-Trained Males

BACKGROUND

The effects of combining resistance training (RT) and concurrent training (CT; resistance + endurance training) with varied protein doses on bone measures remain poorly understood. Hence, we conducted a comparison of the impacts of two high-protein diets (1.6 or 3.2 g kg-1 d-1) over 16 weeks in resistance-trained males, either with CT or RT alone.

METHODS

A total of forty-eight males, all of whom were resistance-trained, had the following demographics: 26.6 ± 6 years, body mass index: 25.6 ± 2.9 kg m-2 administered either 3.2 g kg-1 d-1 protein (CT2; n = 12; RT2; n = 12) or 1.6 g kg-1 d-1 protein (CT1; n = 12; RT1; n = 12) during 16 weeks (four sessions·w-1). Bone parameters were assessed pre- and post-intervention.

RESULTS

There was no significant interaction between the intervention group and time for the legs, arms, ribs, or pelvis area BMC and BMD (p > 0.05). For the BMD of the pelvis and the BMC of the right ribs, however, there were significant time effects noted (p < 0.05). Furthermore, there was a significant interaction between the intervention group and time in the lumbar and thoracic spines, with a particular time effect noted for the thoracic spine region (p < 0.05). The regional differences in skeletal responses to the intervention are highlighted by these data.

CONCLUSION

Our findings show that the intake of two high-protein diets combined with RT and CT during 16 weeks had no adverse effects on bone tissue parameters. While these findings indicate that protein intake between 2 and 3 times the current RDI does not promote bone demineralization when consumed in conjunction with exercise, future studies investigating the long-term effects of chronic high protein intake on bone tissue health are warranted.

Effects of Moderate- to High-Impact Exercise Training on Bone Structure Across the Lifespan: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Moderate- to high-impact exercise improves bone mineral density (BMD) across the lifespan, but its effects on bone structure, which predicts fracture independent of areal BMD, are unclear. This systematic review and meta-analysis investigated effects of impact exercise on volumetric BMD (vBMD) and bone structure. Four databases (PubMed, Embase, SPORTDiscus, Web of Science) were searched up to March 2022 for randomized controlled trials (RCTs) investigating the effects of impact exercise, with ground reaction forces equal to or greater than running, compared with sham or habitual activity, on bone vBMD and structure. Bone variables were measured by quantitative computed tomography or magnetic resonance imaging at the tibia, radius, lumbar spine, and femur. Percentage changes in bone variables were compared among groups using mean differences (MD) and 95% confidence intervals (CI) calculated via random effects meta-analyses. Subgroup analyses were performed in children/adolescents (<18 years), adults (18-50 years), postmenopausal women, and older men. Twenty-eight RCTs (n = 2985) were included. Across all studies, impact exercise improved trabecular vBMD at the distal tibia (MD = 0.54% [95% CI 0.17, 0.90%]), total vBMD at the proximal femur (3.11% [1.07, 5.14%]), and cortical thickness at the mid/proximal radius (1.78% [0.21, 3.36%]). There was no effect on vBMD and bone structure at the distal radius, femoral shaft, or lumbar spine across all studies or in any subgroup. In adults, impact exercise decreased mid/proximal tibia cortical vBMD (-0.20% [-0.24, -0.15%]). In postmenopausal women, impact exercise improved distal tibia trabecular vBMD (0.79% [0.32, 1.25%]). There was no effect on bone parameters in children/adolescents in overall analyses, and there were insufficient studies in older men to perform meta-analyses. Impact exercise may have beneficial effects on bone structure and vBMD at various skeletal sites, but additional high-quality RCTs in different age and sex subgroups are needed to identify optimal exercise protocols for improving bone health across the lifespan. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Micromechanical Loading Studies in Ex Vivo Cultured Embryonic Rat Bones Enabled by a Newly Developed Portable Loading Device

Mechanical loading has been described as having the potential to affect bone growth. In order to experimentally study the potential clinical applications of mechanical loading as a novel treatment to locally modulate bone growth, there is a need to develop a portable mechanical loading device enabling studies in small bones. Existing devices are bulky and challenging to transfer within and between laboratories and animal facilities, and they do not offer user-friendly mechanical testing across both ex vivo cultured small bones and in vivo animal models. To address this, we developed a portable loading device comprised of a linear actuator fixed within a stainless-steel frame equipped with suitable structures and interfaces. The actuator, along with the supplied control system, can achieve high-precision force control within the desired force and frequency range, allowing various load application scenarios. To validate the functionality of this new device, proof-of-concept studies were performed in ex vivo cultured rat bones of varying sizes. First, very small fetal metatarsal bones were microdissected and exposed to 0.4 N loading applied at 0.77 Hz for 30 s. When bone lengths were measured after 5 days in culture, loaded bones had grown less than unloaded controls (p < 0.05). Next, fetal rat femur bones were periodically exposed to 0.4 N loading at 0.77 Hz while being cultured ex vivo for 12 days. Interestingly, this loading regimen had the opposite effect on bone growth, i.e., loaded femur bones grew significantly more than unloaded controls (p < 0.001). These findings suggest that complex relationships between longitudinal bone growth and mechanical loading can be determined using this device. We conclude that our new portable mechanical loading device allows experimental studies in small bones of varying sizes, which may facilitate further preclinical studies exploring the potential clinical applications of mechanical loading.

The Decline of Physical Activity with Age in School-Aged Children with Cerebral Palsy: A Single-Center Cross-Sectional Observational Study

Maintaining physical activity is important for children with cerebral palsy (CP). This study examined whether age predicted habitual physical activity (HPA) or cardiorespiratory fitness (CRF) in school-aged children with CP and clarified the relationship between HPA and CRF. We utilized cross-sectional data from 39 children with CP (18 girls and 21 boys; mean age 7.44 years; mean body weight 24.76 kg; mean body mass index 15.97 kg/m²; hemiplegic or diplegic CP). The participants wore an accelerometer (ActiGraph) for five days to measure HPA, physical activity energy expenditure (kcal/kg/d), sedentary physical activity (%SPA), light physical activity, moderate-to-vigorous physical activity (%MVPA), and activity counts (counts/min). Participants underwent cardiopulmonary exercise tests on a treadmill using a modified Naughton protocol. Linear regression and correlation analyses were performed. p-value (two-tailed) < 0.05 was considered statistically significant. Age was positively associated with SPA. MVPA negatively correlated with resting heart rate (HR), and activity counts were negatively correlated with resting HR. In conclusion, our study found strong evidence of a negative association between HPA and age in school-aged children with CP. It highlights the importance of creating and improving recreational opportunities that promote physical activity in all children with CP, regardless of whether they are considered therapeutic.

The influence of diet and physical activity on bone density of children aged 5-7 years: The Belfast HAPO family study

OBJECTIVE

Osteoporosis is a global health issue, and modifiable behavioural factors need to be identified in childhood to reduce the risk of osteoporosis in later life. The aim of this study was to investigate the influence of diet and physical activity on bone density of children aged 5-7 years participating in the Belfast Hyperglycaemia and Adverse Pregnancy Outcome (HAPO) Family study.

DESIGN AND METHODS

Pregnant women were recruited to the Belfast centre of the HAPO study at 24-32 weeks gestation. Offspring were followed up at 5-7 years as part of the Belfast HAPO Family Study. Heel bone mineral density (BMD) and bone mineral apparent density (BMAD) were measured and calculated, respectively. Physical activity in the offspring was measured by accelerometery and dietary intakes were measured using a 4-day food diary.

RESULTS

Results from 793 offspring were analysed. Mean age of the offspring ± standard deviation was 6.4 ± 0.5 years. A mean of 48.3 ± 22.4 min each day was spent in moderate to vigorous physical activity (MVPA). Median (interquartile range) dietary calcium and vitamin D intakes were 844 (662-1073) mg/day and 1.7 (1.1-2.5) μg/day, respectively. Neither dietary vitamin D nor calcium intakes were significantly associated with offspring heel BMD or BMAD in multiple regression. However, controlling for confounders, a 30-min greater MVPA was associated with significantly larger heel BMD (0.018 g/cm² in boys and 0.010 g/cm² in girls) and BMAD (0.005 g/cm³ in boys and 0.003 g/cm³ in girls).

CONCLUSION

Physical activity was associated with better BMD and BMAD in 5-7-year-old children. Dietary calcium and vitamin D were not predictive of BMD and BMAD.

Bone mineral density in adults with Down syndrome: a cross-sectional study in a Brazilian sample

BACKGROUND

We aim to investigate the relationship between bone mass in a sample of Brazilian individuals with DS and handgrip strength, body mass index (BMI) and physical exercise.

METHODS

Dual-energy X-ray emission densitometry analysis of bone mass in 26 individuals with DS (8 men and 18 women with a mean age of 30.7 ± 10.3 years) was conducted. Additionally, weight and height were measured to determine BMI, palmar grip strength was measured using a Jammar dynamometer®, and physical activity was classified using the International Physical Activity Questionnaire (IPAQ).

RESULTS

In this sample, 2/15 (13.3%) individuals with age between 18 to 29 years had low BMD in the spine; 2/8 (25%) of those with age between 30 and 39 years also had low BMD in the spine and 2/3 (66.6%) with age ≥40 had low BMD in the femur. There were significant correlations between palmar grip strength and Z femoral neck score in women (P = 0.02) and between BMI and Z femoral neck score in men (P = 0.04). All other correlations lacked statistical significance (P > 0.05).

CONCLUSIONS

Brazilian patients with DS showed a high prevalence of low bone mass. Traditional factors such as muscle strength, BMI and physical activity appear to have little effect on bone mineral density in this population.

Diffuse reflectance spectroscopy of the cartilage tissue in the fourth optical window

Studies of the optical properties of biological tissues in the infrared range have demonstrated significant potential for diagnostic tasks. One of the insufficiently explored ranges for diagnostic problems at the moment is the fourth transparency window, or short wavelength infrared region II (SWIR II). A Cr²⁺:ZnSe laser with tuning capability in the range from 2.1 to 2.4 µm was developed to explore the possibilities in this region. The capability of diffuse reflectance spectroscopy to analyze water and collagen content in biosamples was investigated using the optical gelatin phantoms and the cartilage tissue samples during their drying process. It was demonstrated that decomposition components of the optical density spectra correlated with the partial content of the collagen and water in the samples. The present study indicates the possibility of using this spectral range for the development of diagnostic methods, in particular, for observation of the changes in the content of cartilage tissue components in degenerative diseases such as osteoarthritis.

Associations Between Physical Activity and Adolescent Idiopathic Scoliosis: A Systematic Review and Meta-analysis

OBJECTIVE

To investigate the associations between adolescent idiopathic scoliosis (AIS) and physical activity (PA).

DATA SOURCES

MEDLINE, EMBASE, AMED, SPORTDiscus, Cochrane Library, and CINAHL electronic databases were searched from inception to August 2022/plus citation tracking.

STUDY SELECTION

Observational studies of participants with radiographically confirmed AIS with ≥10° lateral spinal curvature (Cobb method) and comparator groups without AIS that measured PA were selected by 2 reviewers.

DATA EXTRACTION

Data were extracted independently and cross-checked by 2 reviewers. Risk of bias was evaluated using Newcastle Ottawa Scales and overall confidence in the evidence using the GRADE approach.

DATA SYNTHESIS

Sixteen studies with 9627 participants (9162, 95% women) were included. A history of vigorous PA significantly reduced the odds of being newly diagnosed with AIS by 24% (odds ratio [OR] 0.76, 95% confidence interval [CI] 0.65-0.89) (high certainty). Moderate PA reduced odds by 13% (moderate certainty) and light PA increased odds by 9% (low certainty), but neither analysis was statistically significant. Ballet or gymnastics (OR 1.47, 95% CI 3.08 (1.90, 5.00) were the only individual sports significantly associated with AIS diagnosis (moderate certainty). Case-control studies of people with and without AIS provided greater evidence that having AIS reduces vigorous PA and sports participation, and less evidence light PA and walking are affected.

CONCLUSION

Adolescents who participate in more vigorous PA are less likely to be diagnosed with AIS. Ballet and gymnastics are associated with AIS diagnosis, but the direction of this association is uncertain. People with AIS are likely to do less vigorous physical and sporting activity compared with those without AIS, which could negatively affect health and quality of life. Further research is warranted into the inter-relations between PA and AIS, studies need to be of sufficient size, include men, and evaluate vigorous including higher-impact PA compared with moderate or light PA.

Esports players, got muscle? Competitive video game players' physical activity, body fat, bone mineral content, and muscle mass in comparison to matched controls

BACKGROUND

Esports players, like traditional athletes, practice for long hours and, thus, are vulnerable to the negative health effects of prolonged sitting. There is a lack of research on the physical activity and the health ramifications of prolonged sitting by competitive players. The purpose of this study was to investigate activity levels, body mass index (BMI), and body composition in collegiate esports players as compared to age-matched controls.

METHODS

Twenty-four male collegiate esports players and non-esports players between 18 and 25 years of age signed a written consent to participate. Physical activity was examined using daily activity (step count) with a wrist-worn activity tracker. A questionnaire assessing physical activity was also administered. Secondary outcomes included body-fat percentage, lean-body mass, BMI, and bone mineral content measured using dual X-ray absorptiometry.

RESULTS

The step count in the esports players was significantly lower than the age-matched controls (6040.2 ± 3028.6 vs. 12843.8 ± 5661.1; p = 0.004). Esports players exhibited greater body-fat percentage (p = 0.05), less lean body mass (p = 0.003), and less bone mineral content (p = 0.03), despite no difference in BMI between the esports and non-esports players.

CONCLUSION

As compared to non-esports players, collegiate esports players were significantly less active and had a higher body-fat percentage, with lower lean body mass and bone mineral content. The BMIs showed no difference between the 2 groups. Esports athletes displayed significantly less activity and poor body composition, which are all correlated with potential health issues and risk of injury. BMI did not capture this difference and should not be considered as an accurate measure of health in competitive esports players.

Dietary inflammatory index and bone mineral density in Mexican population

Dietary inflammatory index has been associated with bone loss. In this longitudinal study, we reported that changes in dietary inflammatory index were associated with a reduction in bone mineral density of the total hip and femoral neck in males and females ≥ 45 years, but not in individuals < 45 years.

PURPOSE

Previous studies have suggested that an inflammatory environment can affect bone mineral density (BMD). However, most of the studies have been done in postmenopausal women. Thus, longitudinal studies in different age groups and sex are necessary to evaluate the longitudinal association between dietary inflammatory index (DII) and BMD in Mexican adults.

METHODS

A total of 1,486 participants of the Health Workers Cohort Study were included in this study. The DII was estimated with data retrieved through a semi-quantitative food frequency questionnaire. Total hip, femoral neck, and lumbar spine BMD were measured by dual-energy X-ray absorptiometry. Linear regression models for cross-sectional associations and fixed effects linear regression models for longitudinal association were estimated, and both models were stratified by sex and age groups (< 45 and ≥ 45 years).

RESULTS

We did not observe cross-sectional associations between DII and the different BMD sites at baseline. In contrast, women and men ≥ 45 years in the 25th quartile of changes in DII were associated with a gain of 0.067 g/cm² and 0.062 g/cm² of total hip BMD, while those in the 75th quartile of DII was associated with a reduction of - 0.108 g/cm² and - 0.100 g/cm², respectively. These results were similar for femoral neck BMD in women. In contrast, we did not observe association with femoral neck BMD in men. We did not observe statistically significant changes for lumbar spine BMD.

CONCLUSION

Our data suggest that changes in the DII score are associated with changes in total hip and femoral neck BMD among Mexican population.

Physical activity estimated by osteogenic potential and energy expenditure has differing associations with bone mass in young adults: the raine study

Ground impacts during physical activity may be important for peak bone mass. We found differences in how energy expenditure and impact scores estimated from a physical activity questionnaire related to bone health in young adults. Using both estimate types can improve our understanding of the skeletal benefits of physical activity.

PURPOSE

It is unclear whether mechanical loading during physical activity, estimated from physical activity questionnaires which assess metabolic equivalents of task (METs), is associated with skeletal health. This longitudinal study investigated how physical activity loading scores, assessed at ages 17 and 20 years, (a) compares with physical activity measured in METs, and (b) is associated with bone mass at age 20 years.

METHODS

A total of 826 participants from the Raine Study Gen2 were assessed for physical activity energy expenditure via the International Physical Activity Questionnaire (IPAQ) at age 17 and 20 years. Loading scores (the product of peak force and application rate) per week were subsequently estimated from the IPAQ. Whole-body and appendicular bone mineral density (BMD) at age 20 years were assessed by dual-energy X-ray absorptiometry.

RESULTS

Bland-Altman minimal detectable difference for physical activity Z- scores at age 17 and 20 years were 1.59 standard deviations (SDs) and 1.33 SDs, respectively, greater than the a priori minimal clinically important change of 0.5 SDs. Loading score, but not IPAQ score, had significant positive associations with whole-body and leg BMD after adjustment for covariates (β = 0.008 and 0.012 g/cm², respectively, for age 17 and 20 years loading scores). IPAQ score at age 20 years, but not loading score, had a significant positive association with arm BMD (β = 0.007 g/cm²).

CONCLUSION

This study revealed disagreement in associations of self-reported METs and loading score estimates with bone health in young adults. Coupling traditional energy expenditure questionnaire outcomes with bone-loading estimates may improve understanding of the location-specific skeletal benefits of physical activity in young adults.

Differences in skeletal growth pattern of yoga practising adolescent girls: A cross-sectional study

Background

Yogasana improves both mental and physical health. There is sparse systematic research on the growth of yogasana practising adolescents.

Objectives

This study aims to assess the differential skeletal growth pattern among pre-adolescent and adolescent girls as a result of yoga practice.

Methods

A cross-sectional anthropometric study was conducted on stature (height), sitting height and leg length of 757 school-going girls (4-15 years old), divided in two groups, Yoga Group (YG) (n=380) and age matched Control Group (CG) (n=377) participants participating in recreational games other than yoga. Descriptive and inferential statistical analyses were applied. Unpaired t-test was performed for assessment of level of significance and Pearson's correlation (r) test was performed to to identify the association between growth pattern of stature and leg length at specific ages.

Results

The physical growth showed an ascending trend in both Yoga group (YG)2 participants and control group (CG)3 . At the onset of adolescence (10–12 years) the mean stature and leg length of YG participants were retarded (p < 0.05). Sitting height in YG was significantly (p < 0.05) low only in 10-year-olds. The similar trends were observed in stature and leg length in YG participants at 10 years (5th and 10th percentile) and 12 years (90th and 95th percentile). There was strong positive relationship between stature and leg length of YG participants (10 years, r = 0.86, p < 0.01; 11 years, r = 0.86, p < 0.01; 12 years, r = 0.72, p < 0.01). The stunted growth in YG participants during adolescence may be related to retarded growth of leg length.

Conclusions

Intense yogasana practice with greater skeletal stress possibly hinders stature in adolescent girls from 10 to 12 years. This may compromise with the natural growth pattern, necessitating special care during yoga training among adolescents while selecting the type, intensity and duration of yogasanas practice.

Regular School Sport versus Dedicated Physical Activities for Body Posture-A Prospective Controlled Study Assessing the Sagittal Plane in 7-10-Year-Old Children

Body posture develops during the growing period and can be documented using trunk photography. The study aims to evaluate the body posture in children aged 7-10 years undergoing a dedicated physical activities program versus regular school sport. A total of 400 children, randomly chosen from a cohort of 9300 participating in a local scoliosis screening program, were evaluated twice at a one-year interval. A total of 167 children were involved in regular school sport (control group), while 233 received both school sport and a dedicated physical activities program (intervention group). Standardized photographic habitual body posture examination was performed at enrollment (T0) and one-year after (T1). Sacral slope (SS), lumbar lordosis (LL), thoracic kyphosis (TK), chest inclination (CI), and head protraction (HP) were measured. At T0, the body posture parameters did not differ between groups. At T1 in the controls, all five parameters tended to deteriorate (insignificant): SS p = 0.758, LL p = 0.38, TK p = 0.328, CI p = 0.081, and HP p = 0.106. At T1 in the intervention group, the SS decreased (p = 0.001), the LL tended to decrease (p = 0.0602), and the TK, CI, and HP remained unaltered. At T1, the SS and LL parameter differed between groups statistically (p = 0.0002 and p = 0.0064, respectively) and clinically (2.52° and 2.58°, respectively). In 7-10-year-old children, participation in dedicated physical activities tends to improve their body posture compared to regular school sport.

The mechanotransduction of MLO-Y4 cells is disrupted by the senescence-associated secretory phenotype of neighboring cells

Age-related bone loss is attributed to the accumulation of senescent cells and their increasing production of inflammatory cytokines as part of the senescence-associated secretory phenotype (SASP). In otherwise healthy individuals, osteocytes play a key role in maintaining bone mass through their primary function of responding to skeletal loading. Given that osteocytes' response to loading is known to steadily decline with age, we hypothesized that the increasing presence of senescent cells and their SASP inhibit osteocytes' response to loading. To test this hypothesis, we developed two in vitro models of senescent osteocytes and osteoblasts derived from MLO-Y4 and MC3T3 cell lines, respectively. The senescent phenotype was unique to each cell type based on distinct changes in cell cycle inhibitors and SASP profile. The SASP profile of senescent osteocytes was in part dependent on nuclear factor-κB signaling and presents a new potential mechanism to target the SASP in bone. Nonsenescent MLO-Y4 cells cultured with the SASP of each senescent cell type failed to exhibit changes in gene expression as well as ERK phosphorylation and prostaglandin E2 release. The SASP of senescent osteocytes had the largest effect and neutralizing interleukin-6 (IL-6) as part of the SASP restored osteocytes' response to loading. The loss in mechanotransduction due to IL-6 was attributed to a decrease in P2X7 expression and overall sensitivity to purinergic signaling. Altogether, these findings demonstrate that the SASP of senescent cells have a negative effect on the mechanotransduction of osteocytes and that IL-6 is a key SASP component that contributes to the loss in mechanotransduction.

Relationship Between Gymnastic Rhythmic Practice and Body Composition, Physical Performance, and Trace Element Status in Young Girls

This study evaluates the influence on body development of doing rhythmic gymnastics in girls from 10 to 17 years of age, the results of certain strength and flexibility abilities, and the trace element status (Ca, Fe, Zn, Cu, Mn, Cr, and Ni). The subjects were divided into three groups: (a) girls who practiced rhythmic gymnastics at a competition level (competition group); (b) girls who practiced this sport at a non-competitive level (training group); and (c) girls who do not practice any sport and with a low level of physical activity (control or sedentary group). Trace element status was determined in hair and urine samples. Results showed that doing rhythmic gymnastics does not alter the normal physical development of muscle mass, and even leads to a decrease in body fat content. Furthermore, better scores in the strength and flexibility test were obtained by the participants of this sports discipline. Statistically significant differences in urine Fe, Cu, and Mn values (p < 0.05) and in hair Cr, Cu, and Mn values (p < 0.05) were found between the two rhythmic gymnastics groups and the control group, and were higher in the competition and training groups. A principal component analysis model was performed to evaluate the possibility of cluster formation among the girls. The PCA results revealed a separation between the different groups although the separation was not perfect. PLS-DA was attempted in order to verify whether it was possible to discriminate between the groups included in this study. It was clear that the competition and control ones were very well classified (around 95% of correct predictions) but 20% of the girls belonging to the training group were misclassified as belonging to the competition one.

Adolescent female handball players present greater bone mass content than soccer players: A cross-sectional study

BACKGROUND

Osteoporosis is a systemic disease affecting half of women over the age of 50 years. Considering that almost 90% of peak of bone mass is achieved until the second decade of life, ensuring a maximal bone mineral content acquisition may compensate for age-associated bone loss. Among several other factors, physical activity has been recommended to improve bone mass acquisition. However, it is unknown whether athletes involved with sports with different impact loading characteristics differ in regards to bone mass measurements.

AIM

To compare the bone mass content, bone mass density and lean mass of young female soccer players (odd-impact loading exercise), handball players (high-impact loading exercises) and non-athletes.

METHODS

A total of 115 female handball players (15.5 ± 1.3 years, 165.2 ± 5.6 cm and 61.9 ± 9.3 kg) and 142 soccer players (15.5 ± 1.5 years, 163.7 ± 6.6 cm and 56.5 ± 7.7 kg) were evaluated for body composition using a dual-emission X-ray absorptiometry system, and 136 female non-athletes (data from NHANES) (15.1 ± 1.32 years, 163.5 ± 5.8 cm and 67.2 ± 19.4 kg) were considered as the control.

RESULTS

Handball players presented higher bone mass content values than soccer players for upper limbs (294.8 ± 40.2 g and 270.7 ± 45.7 g, p < 0.001), lower limbs (1011.6 ± 145.5 g and 967.7 ± 144.3 g, p = 0.035), trunk (911.1 ± 182.5 g and 841.6 ± 163.7 g, p = 0.001), ribs (312.4 ± 69.9 g and 272.9 ± 58.0 g, p < 0.001), spine (245.1 ± 46.8 g and 222.0 ± 45.1 g, p < 0.001) and total bone mass (2708.7 ± 384.1 g and 2534.8 ± 386.0 g, p < 0.001). Moreover, non-athletes presented lower bone mass content for lower limbs (740.6 ± 132.3 g, p < 0.001), trunk (539.7 ± 98.6 g, p < 0.001), ribs (138.2 ± 29.9 g, p < 0.001), pelvis (238.9 ± 54.6 g, p < 0.001), spine (152.8 ± 26.4 g, p < 0.001) and total bone mass (1987.5 ± 311.3 g, p < 0.001) than both handball and soccer players. Handball players also presented higher bone mass density values than soccer players for trunk, ribs and spine (p < 0.05) and handball and soccer players presented higher bone mass density than non-athletes for all measurements (p < 0.005). Finally, the non-athletes' lower limb lean mass was lower than soccer and handball players values (p < 0.05).

CONCLUSION

Adolescent females engaged in handball training for at least one year present higher bone mass contents than those who are engaged in soccer training, which, in turn, present higher bone mass contents than non-athletes. These results might be used by physicians and healthcare providers to justify the choice of a particular sport to enhance bone mass gain in female adolescents.

Acute Effects of Strength and Endurance Training on Bone Turnover Markers in Young Adults and Elderly Men

CONTEXT

Exercise is recognized as an important strategy to prevent bone loss, but its acute effects on bone turnover markers (BTMs) and related markers remain uncertain.

OBJECTIVE

To assess the acute effects of two different exercise modes on BTMs and related markers in young adults of both sexes and elderly men.

DESIGN SETTING PARTICIPANTS

This was a three-group crossover within-subjects design study with a total of 53 participants-19 young women (aged 22-30), 20 young men (aged 21-30 years), and 14 elderly men (aged 63-74 years)-performing two different exercise sessions [strength training (ST) and high-intensity interval training (HIIT)] separated by 2 weeks, in a supervised laboratory setting.

MAIN OUTCOME MEASURES

Plasma volume-corrected serum measurements of the BTMs C-terminal telopeptide of type 1 collagen (CTX-I) and procollagen of type 1 N-terminal propeptide (P1NP), total osteocalcin (OC), sclerostin, and lipocalin-2 (LCN2) at baseline, immediately after, and 3 and 24 h after each of the two exercise modes were performed.

RESULTS AND CONCLUSION

Analyses revealed sex- and age-dependent differences in BTMs and related bone markers at baseline and time-, sex-, and age-dependent differences in response to exercise. No differences between exercise modes were observed for BTM response except for sclerostin in young men and LCN2 in elderly men. An acute, transient, and uniform increase in P1NP/CTX-1 ratio was found in young participants, demonstrating that beneficial skeletal effects on bone metabolism can be attained through both aerobic endurance and resistance exercise, although this effect seems to be attenuated with age. The acute effects of exercise on bone-related biomarkers were generally blunted after 24 h, suggesting that persistent alterations following prolonged exercise interventions should be assessed at later time points.

Relationship between physical activity, lean body mass, and bone mass in the Mexican adult population

We evaluated the association between leisure-time physical activity (LTPA), bone mineral content (BMC), and lean mass (LM) in whole body (wb) and limbs of the Mexican adult population. Our results demonstrate that some types of LTPA with relatively high/medium impact on bones such as football, basketball, tennis, and weightlifting improve BMC and LM.

PURPOSE

To evaluate the effect of different kinds of leisure-time physical activity (LTPA) on bone mass values and its association with lean mass (LM) in the whole body (wb) and limbs of a large sample of Mexican men and premenopausal (pre-MP) women.

METHODS

We conducted a cross-sectional analysis of data from the Health Workers Cohort Study. Bone mineral content (BMC, kg), bone area (cm²), and LM (kg) were measured with DXA. The LTPA level and the "sedentary" condition were determined using a validated questionnaire adapted for the Mexican population. One-way ANOVA tests evaluated the differences in weight, height, body mass index, and wb, lower limb (ll) and upper limb (ul) BMC and LM between the active (those who engaged in LTPA) and sedentary group. Relationships between BMC and LM values were analyzed. Slopes of the curves and Z scores of LTPA groups with respect to the sedentary group were compared.

RESULTS

In men, both wb-BMC and ll-BMC were significantly higher in the groups performing basketball, football, tennis, weightlifting, and running, and all wb-LM, ll-LM, and ul-LM were higher in running, weightlifting, football, and basketball groups with respect to the sedentary group. Both the Z scores and the slopes of BMC-vs-LM relationships were higher than the controls, but only in the ll of male basketball and football players.

CONCLUSION

Our findings demonstrate that some types of LTPA with relatively high/medium impact on bones, such as football, basketball, tennis, and weightlifting, improve both BMC and LM compared to sedentary individuals. Finally, this relationship is stronger for the bones found in the legs and it seems that women are less sensitive to this effect, possibly due to hormonal, dietary, and pharmacological reasons.

Bone mineral density in elite masters athletes: the effect of body composition and long-term exercise

BACKGROUND

The purpose of the study was to examine how bone mineral density (BMD) is related to body composition depending on the practiced sport (endurance, speed-power, throwing sports) in participants of the World Masters Athletics Championship.

METHODS

Dual-energy X-ray absorptiometry (DXA) was used to determine BMD and bone mass (BMC). Body composition was analyzed by means of the JAWON Medical X-scan analyzer using bioelectrical impedance methods. Percentage body fat (%BF), body fat mass (BFM), lean body mass (LBM), total body water (TBW), soft lean mass (SLM), intracellular water (ICW), and extracellular water (ECW) were evaluated.

RESULTS

Among men, the most important variables affecting the BMD norm were LBM (OR = 32.578; p = 0.023), ECW (OR = 0.003; p = 0.016) and ICW (OR = 0.011; p = 0.031), in the distal part and SLM (OR = 5.008; p = 0.020) and ICW (0.354, p = 0.008) in the proximal part. In women, the most important predictors of normal BMD were ICW (OR = 10.174; p = 0.003) and LBM (OR = 0.470; p = 0.020) in the distal part and ICW (OR = 5.254; p = 0.038) in the proximal part.

CONCLUSION

The representatives of strength based events had the most advantageous BMD levels. The condition of bone tissue evaluated by BMC and BMD of the forearm in masters athletes was strongly determined by the level of lean body components and the type of sports training associated with the track and field event. In the most important predictors of the BMD norm were also hydration components ECW and ICW. However, this relationship requires more research on the nature and mechanisms of these interactions.

Bone Metabolism, Bone Mineral Content, and Density in Elite Late Teen Female Sprinters

With intensive training, bone injuries are a major concern for athletes. To assess bone condition, we often measure bone turnover markers, bone mineral content and density; however, in junior athletes, it is not easy to distinguish changes caused by bone injuries from those caused by growth, because the metabolism is increased in both cases. Moreover, although some studies have examined female endurance athletes, knowledge regarding changes in static and dynamic bone conditions in late teen athletes is limited. In this study, we measured the bone mineral content and density, as well as bone turnover markers, in 40 elite female sprinters in their late teens. Whole body mode dual-energy X-ray absorptiometry was performed to measure bone mineral content and density. Blood samples were collected to determine bone resorption and formation markers at the end of track season in 2016 and during the same period of the following year. Body weight and bone mineral content significantly increased, and tartrate-resistant acid phosphatase type 5b, bone-type alkaline phosphatase, and osteocalcin significantly decreased after a year. Furthermore, the rate of change in bone mineral content was higher in younger athletes, indicating that bone growth approaches completion in the late teen years and that bone metabolism accordingly decreases.

Association Between Vertebral Dimensions and Lumbar Modic Changes

STUDY DESIGN

Population-based birth cohort study.

OBJECTIVE

The aim of this study was to evaluate the relationship between vertebral dimensions and lumbar MC.

SUMMARY OF BACKGROUND DATA

Low back pain (LBP) has become the leading cause of disability worldwide. Modic changes (MC) of the lumbar spine are one potential LBP-associated etiological factor. Mechanical stress is considered to play a key role in the development of MC through damage to endplates. There is speculation that vertebral dimensions play a role in some degenerative changes in the spine. Previous studies have also shown a positive association between moderate-to-vigorous physical activity (MVPA) and both vertebral dimensions and MC. In this study, we aimed to evaluate the relationship between vertebral dimensions and MC.

METHODS

The study population consisted of 1221 participants from the Northern Finland Birth Cohort 1966 who underwent lumbar magnetic resonance imaging (MRI) and physical activity measurements at the age of 46-48. The presence of Type 1 (MC1) and Type 2 (MC2) MC and the height, axial cross-sectional area (CSA), and volume of the L4 vertebra were determined from MRI scans. MVPA (≥3.5 metabolic equivalents) was measured by a wrist-worn accelerometer. We analyzed the association between lumbar MC and vertebral height, CSA, and volume using logistic regression models before and after adjustment for sex, height, weight, smoking, education level, and MVPA.

RESULTS

Vertebral height was positively associated with the presence of MC2 (odds ratio [OR] 3.51; 95% confidence interval [CI] 1.43-8.65), whereas vertebral CSA was not associated with the presence of lumbar MC. Vertebral volume was positively associated with the presence of any MC (OR 1.04; 95% CI 1.00-1.07), but the association did not persist when analyzing MC1 and MC2 separately.

CONCLUSION

Vertebral height was associated with the presence of MC2. Further studies are needed to clarify the role of vertebral dimensions as independent risk factors for MC.Level of Evidence: 3.

Effectiveness of interventions and behaviour change techniques for improving physical activity in young adults: A systematic review and meta-analysis

Physical activity (PA) participation declines from adolescence to young adulthood. This review evaluates the effectiveness of interventions aiming to improve PA among healthy young adults (17-35 years), and the effectiveness of the behaviour change techniques (BCTs) used. Six electronic databases were searched up to December 2019, for randomized controlled trials aiming to achieve PA behaviour change among young adults. In total, 66 RCTs were included. Meta-analyses for moderate-vigorous PA (n = 11 studies), steps (n = 5 studies) and total PA (MET min/week, n = 11 studies) identified that intervention participants compared with control significantly increased PA at time points up to 3 months and >3 months. Narrative synthesis identified that 34 RCTs (52%) reported significant between group differences favouring the intervention for one or more PA outcome. BCTs with the highest effectiveness were material reward, valued self-identity and habit formation. However, the overall test of significance demonstrated no significant relationship between type or number of BCTs and effectiveness. This review identified interventions that improve steps, moderate-vigorous and total PA in young adults in the shorter-term, and BCTs associated with greater effectiveness. Further research is needed to determine strategies to achieve longer-term effectiveness of PA interventions in young adults.

The association of asthma and its subgroups with osteoporosis: a cross-sectional study using KoGES HEXA data

Background

A few studies have reported the association between asthma and osteoporosis. We aimed to analyze the association of asthma and its subgroups with osteoporosis in the Korean adult population.

Methods

We used the health examinee (HEXA) data from the Korean Genome and Epidemiology Study (KoGES) obtained between 2004 and 2016. We included 162,579 participants (n = 3,160 with asthma; n = 159,419 controls) who reported their previous histories of asthma and osteoporosis. The participants were categorized into 3 groups based on asthma management: participants who did not need further treatment due to controlled symptoms (well controlled); participants with ongoing treatment (being treated); participants who were not treated even though they had symptoms (not being treated). Multiple logistic regression analyses were used to calculate the adjusted odds ratios (aORs) with 95% confidence intervals (CIs) for osteoporosis. Subgroup analyses for age and sex were conducted.

Results

The prevalence of osteoporosis was higher in patients with asthma (13.6%) than in controls (6.8%). In the full-adjusted model, the aORs for osteoporosis were 1.74 (95% CI 1.55-1.94, P < 0.001) in patients with asthma compared to controls. There were consistent findings across the age and sex subgroups. The aORs for osteoporosis were 1.43 (95% CI 1.10-1.86, P = 0.008) in the well-controlled asthma group; 1.55 (95% CI 1.28-1.89, P < 0.001) in the being treated asthma group; and 1.96 (95% CI 1.66-2.31, P < 0.001) in the not being treated asthma group compared to the control group.

Conclusion

Asthma was associated with osteoporosis in the Korean adult population. Patients with asthma not being treated showed the highest ORs for osteoporosis.

Epidemiological Study on the Dose-Effect Association between Physical Activity Volume and Body Composition of the Elderly in China

Purpose: The purpose of this study was to investigate Chinese old adults’ different body compositions in response to various levels of physical activity (PA). To the best of our knowledge, this is the first study to demonstrate the dose–response relationship between PA and body composition in old adults. Methods: 2664 participants older than 60 years (males: n = 984, females: n = 1680) were recruited for this cross-sectional health survey. PA was assessed by the short form of the International Physical Activity Questionnaire (IPAQ), and the body composition was measured by bioelectrical impedance analysis (BIA) instruments. The differences of separate body composition indices (lean body mass, LBM; bone mass, BM; and fat mass, FM) of older participants with different PA levels (below PA recommendation and over PA recommendation) were examined using the one-way analysis of variance (ANOVA). To compare the differences of three body composition indices with six different multiples of PA recommendation (0–1 REC, 1–2 REC, 2–4 REC, 4–6 REC, >6 REC), the one-way ANOVA and Turkey’s test was used for the post hoc analysis to identify the upper PA-benefit threshold in different indices of body composition. Results: The LBM and BM are significantly higher and the FM are significantly lower in old adults performing more PA volume than the WHO recommendation, compared with individuals performing less PA volume than the WHO recommendation. There were significant increases in LBM for males in “1–2 REC”, “2–4 REC”, and “>6 REC” groups, compared with the “0–1 REC” group; and there were significant increases in BM for males in “1–2 REC”, “2–4 REC”, compared with the “0–1 REC” group. The best PA volume for LBM and BM in females was the PA volume of “2–4 REC”. Additionally, whether males or females, there was no significant difference in FM between the “0–1 REC” group and other separate groups. Conclusion: The PA volume that causes best benefit for body composition of the elderly occurs at 1 to 2 times the recommended minimum PA for males, while it occurs at 2 to 4 times that recommended for females. No additional harms for old adults’ body composition occurs at six or more times the recommended minimum PA.

Influence of General Mineral Condition on Collagen-Guided Alveolar Crest Augmentation

The local regeneration of bone defects is regulated by general hormone, enzyme, ion, and vitamin levels. General diseases and dysregulation of the human mineral system can impact this process, even in alveolar crest. The aim of this study is to investigate a relation between bone density, measured in two-dimensional X-rays, and general mineral condition of patients. The study included 42 patients on whom tooth extractions were performed. Data were divided into two groups: the region where collagen scaffold (BRM) was used and the reference region of intact normal bone (REF). Two-dimensional intraoral radiographs were taken in all cases just after the surgery (00 M) and 12 months later (12 M). Thyrotropin (TSH), parathormone (PTH), Ca²⁺ in serum, HbA1c, vitamin 25(OH)D₃, and spine densitometry were checked. Digital texture analysis in MaZda 4.6 software was done. Texture Index (TI: BRM 1.66 ± 0.34 in 00 M, 1.51 ± 0.41 in 12 M, and REF 1.72 ± 0.28) and Bone Index (BI: BRM 0.73 ± 0.17 in 00 M, 0.65 ± 0.22 41 in 12 M, and REF 0.80 ± 0.14) were calculated to evaluate bone regeneration process after 12 months of healing (TI (p < 0.05) and BI (p < 0.01) are lower in BRM 12 M than in REF). This showed a relation between BI and TSH (R² = 26%, p < 0.05), as well as a between BI and patient age (R² = 65%, p < 0.001), and a weak relation between TI and TSH level (R² = 10%, p < 0.05). This study proved that a collagen scaffold can be successfully used in alveolar crest regeneration, especially in patients with a high normal level of TSH in the middle-aged population.

Impact of physical activity and exercise on bone health in patients with chronic kidney disease: a systematic review of observational and experimental studies

Background

Chronic Kidney Disease (CKD) patients frequently develop life-impairing bone mineral disorders. Despite the reported impact of exercise on bone health, systematic reviews of the evidence are lacking. This review examines the association of both physical activity (PA) and the effects of different exercise interventions with bone outcomes in CKD.

Methods

English-language publications in EBSCO, Web of Science and Scopus were searched up to May 2019, from which observational and experimental studies examining the relation between PA and the effect of regular exercise on bone-imaging or -outcomes in CKD stage 3–5 adults were included. All data were extracted and recorded using a spreadsheet by two review authors. The evidence quality was rated using the Cochrane risk of bias tool and a modified Newcastle-Ottawa scale.

Results

Six observational (4 cross-sectional, 2 longitudinal) and seven experimental (2 aerobic-, 5 resistance-exercise trials) studies were included, with an overall sample size of 367 and 215 patients, respectively. Judged risk of bias was low and unclear in most observational and experimental studies, respectively. PA was positively associated with bone mineral density at lumbar spine, femoral neck and total body, but not with bone biomarkers. Resistance exercise seems to improve bone mass at femoral neck and proximal femur, with improved bone formation and inhibited bone resorption observed, despite the inconsistency of results amongst different studies.

Conclusions

There is partial evidence supporting (i) a positive relation of PA and bone outcomes, and (ii) positive effects of resistance exercise on bone health in CKD. Prospective population studies and long-term RCT trials exploring different exercise modalities measuring bone-related parameters as endpoint are currently lacking.

Effectiveness of gender-targeted versus gender-neutral interventions aimed at improving dietary intake, physical activity and/or overweight/obesity in young adults (aged 17-35 years): a systematic review and meta-analysis

BACKGROUND

Young adulthood has become synonymous with the development of poor lifestyle behaviours associated with an increased risk of preventable chronic disease in later years. Interventions aiming to improve health behaviours may be more engaging and effective if they are targeted to males or females than interventions with a gender-neutral approach. This review will examine the outcome effectiveness of gender-targeted and gender-neutral interventions targeting nutrition, physical activity or overweight/obesity in young adults (17-35 years).

METHODS

Six electronic databases were searched for randomised controlled trials (RCTs) published up to December 2019 that evaluated nutrition, physical activity and/or overweight/obesity interventions in young adults (17-35 years). An effective intervention was one where the change in one or more primary outcome was positive and statistically significantly different from baseline, compared with control, or if no control comparator, compared with another active intervention. Effectiveness of outcomes was compared between gender-targeted and gender-neutral studies.

RESULTS

In total 21,582 manuscripts were identified and 107 RCTs were included; 30 gender-targeted studies (28%) and 77 gender-neutral (72%). Most gender-targeted studies were female targeted (n = 22, 73%). Primary outcome/s were adiposity (n = 36, 34%), nutrition (n = 29, 27%), physical activity (n = 28, 26%), or a combination of (n = 14, 14%). A greater proportion of gender-targeted than gender-neutral studies were effective in improving nutrition (n = 6, 100% and n = 17, 74% of studies respectively) and physical activity outcomes (n = 6, 86% and n = 14, 67% respectively), where as a greater proportion of gender-neutral studies were effective in improving adiposity outcomes (n = 13, 59% and n = 5, 36% respectively). None of these differences were statistically significant. Meta-analyses for weight found no significant differences between gender-targeted and gender-neutral studies for weight loss or weight gain prevention studies. Meta-analysis for fruit and vegetable intake demonstrated a significantly greater increase in intervention participants in gender-targeted studies of +158 g/day for > 3 months.

CONCLUSIONS

Although differences in outcome effectiveness were identified between gender-targeted and gender-neutral studies, these were not significantly different. This is likely due to an insufficient number of studies to detect a difference. The meta-analysis for fruit and vegetable intake findings should be interpreted with caution due to including only two gender-targeted studies. The findings collectively are suggestive of a potential difference requiring further investigation. To truly determine the effectiveness of gender-targeted interventions, well-designed RCTs comparing gender-targeted interventions with gender-neutral and control are needed.

REGISTRATION

This systematic review is a secondary analysis of studies included in a systematic review examining the effectiveness of interventions targeting nutrition, physical activity, or overweight/obesity in young adults, for which a predefined protocol was registered with PROSPERO (CRD42017075795).

How to manage osteoporosis before the age of 50

This narrative review discusses several aspects of the management of osteoporosis in patients under 50 years of age. Peak bone mass is genetically determined but can also be affected by lifestyle factors. Puberty constitutes a vulnerable period. Idiopathic osteoporosis is a rare, heterogeneous condition in young adults due in part to decreased osteoblast function and deficient bone acquisition. There are no evidence-based treatment recommendations. Drugs use can be proposed to elderly patients at very high risk. Diagnosis and management of osteoporosis in the young can be challenging, in particular in the absence of a manifest secondary cause. Young adults with low bone mineral density (BMD) do not necessarily have osteoporosis and it is important to avoid unnecessary treatment. A determination of BMD is recommended for premenopausal women who have had a fragility fracture or who have secondary causes of osteoporosis: secondary causes of excessive bone loss need to be excluded and treatment should be targeted. Adequate calcium, vitamin D, and a healthy lifestyle should be recommended. In the absence of fractures, conservative management is generally sufficient, but in rare cases, such as chemotherapy-induced osteoporosis, antiresorptive medication can be used. Osteoporosis in young men is most often of secondary origin and hypogonadism is a major cause; testosterone replacement therapy will improve BMD in these patients. Diabetes is characterized by major alterations in bone quality, implying that medical therapy should be started sooner than for other causes of osteoporosis. Primary hyperparathyroidism, hyperthyroidism, Cushing's syndrome and growth hormone deficiency or excess affect cortical bone more often than trabecular bone.

Bone accrual over 18 months of participation in different loading sports during adolescence

This study investigated the impact and non-impact sports on bone mineral density accrual in adolescents over 18 months. The impact sports were beneficial for bone health (accrual of bone density). In contrast, swimmers had similar or lower bone mineral density compared with the control group depending on the skeletal site.

PURPOSE

To investigate the impact and non-impact sports on bone mineral density (BMD) accrual in adolescents over a period of 18 months METHODS: The sample was composed of 71 adolescents, avarage age of 12.7 (± 1.7) years old at baseline. Bone outcomes were compared according to the loading of the sports practiced (impact sports, n = 33 [basketball, karate, and judo], non-impact sport, n = 18 [swimming], and control group, n = 20). Areal bone mineral density (aBMD) was measured by dual-energy X-ray absorptiometry (DXA) and bone mineral apparent density (BMAD) estimated through equation. The results were compared between the groups using analysis of variance and analysis of covariance.

RESULTS

Adjusted aBMD at lower limbs, whole body less head (WBLH), and adjusted WBLH BMAD were significantly greater in the impact sport group than the non-impact sport group at all time points. Adjusted upper limbs aBMD was significantly higher at the impact sports group compared to the non-impact sport group at 9 months and 18 months, besides compared to the control group at baseline and 18 months. Non-impact sport group presented a significant lower adjusted aBMD compared with control group at lower limbs and WBLH at 9 months, and at 9 months and 18 months in WBLH BMAD. There was a significant interaction (time × sport group) at upper limbs (p = 0.042) and WBLH aBMD (p = 0.006), and WBLH BMAD (p < 0.001).

CONCLUSION

Impact sports were more beneficial on accumulating aBMD and BMAD over a period of 18 months, while non-impact group (swimmers) had similar and lower aBMD and BMAD compared with the control group.

Age related changes in the bone microstructure in patients with femoral neck fractures

BACKGROUND

The risk of femoral neck fracture progressively increases with age. However, the reasons behind this consistent increase in the fracture risk can't be completely justified by the decrease in the bone mineral density. The objective of this study was to analyze the correlation between various bone structural features and age.

STUDY DESIGN & METHODS

A total of 29 consecutive patients who suffered an intracapsular hip fracture and underwent joint replacement surgery between May 2012 and March 2013 were included in this study. A 2 cm × 1 cm Ø cylindrical trabecular bone sample was collected from the femoral heads and preserved in formaldehyde. Bone mineral density (BMD), microarchitecture, organic content and crystallography were analyzed using a Dual-energy X-ray absorptiometry scan, micro-CT scan, and high resolution magic-angle-spinning-nuclear magnetic resonance (MAS-NMR), respectively. Statistical correlations were made using Spearman´s or Pearson´s correlation tests depending on the distribution of the continuous variables.

RESULTS

The mean patient age was 79.83 ± 9.31 years. A moderate negative correlation was observed between age and the hydrogen content in bone (¹H), which is an indirect estimate to quantify the organic matrix (r = -0.512, p = 0.005). No correlations were observed between BMD, trabecular number, trabecular thickness, phosphorous content, apatite crystal size, and age (r = 0.06, p = 0.755; r = -0.008, p = 0.967; r = -0.046, p = 0.812; r = -0.152, p = 0.430, respectively). A weak positive correlation was observed between Charlson´s comorbidity index (CCI) and c-axis of the hydroxiapatite (HA) crystals (r = -0.400, p = 0.035).

CONCLUSION

The femoral head relative protein content progressively decreases with age. BMD was not correlated with other structural bone parameters and age. Patients with higher comorbidity scores had larger HA crystals. The present results suggest that the progressive increase in the hip fracture risk in elderly patients could be partially explained by the lower bone protein content in this age group.

Determinants of low bone mineral density in people with multiple sclerosis: Role of physical activity

BACKGROUND

People with multiple sclerosis (PwMS) have reduced bone mineral density (BMD), but the causes are unclear. Some factors that may cause reduced BMD in PwMS have been understudied, including physical activity, inflammation, cortisol, symptomatic fatigue, and depression. The aim of this study was to investigate factors that may uniquely contribute to reduced BMD in PwMS as compared to people without MS. We hypothesized that physical activity would be the primary determinant of low BMD in PwMS, with additional contributions from inflammation and sympathetic nervous system activation.

METHODS

We tested 23 PwMS (16 women; median EDSS: 2) and 22 control participants (16 women). BMD was measured from the femoral neck and lumbar spine with dual x-ray absorptiometry. Disability was measured with the Expanded Disability Status Scale, and functional capacity was measured with the Multiple Sclerosis Functional Composite. Questionnaires measured symptomatic fatigue and depression. A blood draw was used to measure calcium, phosphate, vitamin D, N-terminal telopeptide, osteopontin, and cytokine markers of inflammation. Physical activity was measured with accelerometry. Salivary cortisol and cardiac heart rate variability also were obtained. All outcome variables were compared between groups with independent samples t-tests. Variables that were different between groups and significantly correlated (Pearson product-moment) with femoral neck BMD, were included in a theoretical model to explain femoral neck BMD. The expected direction of relations in the theoretical model were developed based upon the results of previous research. A Bayesian path analysis was used to test the relations of predictive variables with femoral neck BMD and interrelations among predictive variables, as detailed in the theoretical model.

RESULTS

PwMS had lower BMD at the femoral neck than controls (p = =0.04; mean difference: -0.09; 95% CI: -0.2, -0.004; Cohen's d = =0.65), and there was a smaller, statistically non-significant difference in BMD at the lumbar spine (p = =0.07; mean difference: -0.08; 95% CI: -0.17, 0.007; Cohen's d = =0.59). PwMS also had lower functional capacity (p ≤ 0.001; Cohen's d = =1.50), greater fatigue (p<0.001; Cohen's d = =1.88), greater depression (p<0.001; d = =1.31), and decreased physical activity (p = =0.03; Cohen's d = =0.62). Using path analysis to test our theoretical model, we found that disability (standardized estimate= -0.17), physical activity (standardized estimate=0.39), symptomatic fatigue (standardized estimate= -0.36), depression (standardized estimate= -0.30), and inflammatory markers (standardized estimate=0.27) explained 51% of the variance in femoral neck BMD. Inflammatory markers were also predictive of disability (standardized estimate=0.44) and physical activity (standardized estimate= -0.40). Symptomatic fatigue and depression were correlated (r = =0.64).

CONCLUSION

Physical activity, symptomatic fatigue, depression, disability, and inflammation all contributed independently to decreased femoral neck BMD in PWMS. Bone metabolism in PwMS is complex. Efforts to increase physical activity and address symptomatic fatigue and depression may improve bone mineral density in PwMS. Future research should investigate the mechanisms through which symptomatic fatigue and depression contribute to reduced BMD in PwMS.

Bone Health and Its Relationship with Impact Loading and the Continuity of Physical Activity throughout School Periods

Bone is influenced by physical activity (PA) throughout life, but childhood and adolescence provide a key opportunity to maximize peak bone mass. Thus, it is important to identify the relationship between PA practiced in childhood and young adulthood to design a promotion plan for bone health. The purpose of this study was to analyze the relationship between different impact-loading PAs (and their continuity throughout school periods from childhood to young adulthood) and bone stiffness index (SI). In this cross-sectional study, which was conducted on 145 university students aged 18-21 years, bone measurements were measured by quantitative ultrasonometry (QUS), and PA information was recalled using a self-administered questionnaire. Associations between the SI and the impact of PA performed during secondary school (p = 0.027), high school (p = 0.002), and university (p = 0.016) periods were observed. The continuity of PA over a longer period of time was related to a higher SI (p = 0.007). Those who practiced PA throughout all school periods had a higher SI than those who practiced during primary school only (p = 0.038) or through primary and secondary schools (p = 0.009). These results suggest that impact-loading PA practiced during different school periods is related to higher values of the SI. Therefore, continuous PA from an early age may be an important contributing factor to achieving and maintaining adequate bone health.

Participation in school and physical education in juvenile idiopathic arthritis in a Nordic long-term cohort study

BACKGROUND

The aim of the study was to describe school attendance and participation in physical education in school among children with juvenile idiopathic arthritis (JIA).

METHODS

Consecutive cases of JIA from defined geographical areas of Finland, Sweden and Norway with disease onset in 1997 to 2000 were followed for 8 years in a multi-center cohort study, aimed to be as close to population-based as possible. Clinical characteristics and information on school attendance and participation in physical education (PE) were registered.

RESULTS

Participation in school and in PE was lowest initially and increased during the disease course. Eight years after disease onset 228/274 (83.2%) of the children reported no school absence due to JIA, while 16.8% reported absence during the last 2 months due to JIA. Full participation in PE was reported by 194/242 (80.2%), partly by 16.9%, and none by 2.9%. Lowest participation in PE was found among children with ERA and the undifferentiated categories. Absence in school and PE was associated with higher disease activity measures at the 8-year visit. School absence > 1 day at baseline predicted use of disease-modifying anti-rheumatic drugs, including biologics (DMARDs) (OR 1.2 (1.1-1.5)), and non-remission off medication (OR 1.4 (1.1-1.7) 8 years after disease onset.

CONCLUSION

School absence at baseline predicted adverse long-term outcome. In children and adolescents with JIA participation in school activities is mostly high after 8 years of disease. For the minority with low participation, special attention is warranted to promote their full potential of social interaction and improve long-term outcome.

Is vigorous-intensity physical activity required for improving bone mass in adolescence? Findings from a Brazilian birth cohort

The association between moderate and vigorous physical activity throughout adolescence and areal bone density (aBMD) at 18 years of age was evaluated. Vigorous-intensity physical activity at 11, 15, and 18 years was associated with aBMD in early adulthood, especially in boys. Cross-sectional analyses showed a positive association between moderate physical activity and aBMD.

INTRODUCTION

To evaluate independent associations of moderate and vigorous physical activity (MPA, VPA) across adolescence with areal bone mineral density (aBMD).

METHODS

Physical activity (PA) was assessed at 11, 15, and 18 years of age by self-report and at 18 years by accelerometry in the 1993 Pelotas Birth Cohort Study. Time spent in MPA and VPA was determined using metabolic equivalents and specific cutoffs based on raw acceleration. Lumbar spine and femoral neck aBMD were measured by DXA at 18 years. Statistical analyses evaluated the association of MPA and VPA with aBMD, after adjusting for skin color, asset index, current height and age at menarche, and peak strain score (based on ground reaction forces of PA).

RESULTS

Lumbar spine and femoral neck aBMD were available for 3947 (49.9% of boys) and 3960 (49.6% of boys) individuals, respectively. Time spent in MPA at 11 and 15 years was not associated with aBMD. VPA at all time points was positively related to both lumbar spine and femoral neck aBMD in boys. Results were consistent for objectively measured VPA. Girls who achieved 75+ minutes/week of VPA in at least two follow-ups showed higher aBMD at 18 years of age. Boys who reached 75+ minutes/week of VPA at all follow-ups had on average 0.117 g/cm² (95% CI: 0.090; 0.144) higher femoral neck aBMD than those who never achieved this threshold.

CONCLUSIONS

Self-reported VPA but not MPA throughout adolescence was associated with aBMD. Recommendation for PA in young people should consider the importance of VPA.

Effects of a 3-month weight-bearing and resistance exercise training on circulating osteogenic cells and bone formation markers in postmenopausal women with low bone mass

Osteoporosis is a health issue in postmenopausal women. Physical activity is recommended in these subjects, since it has positive effects on bone mass. Cellular mechanisms underlying this effect are still unclear. Osteogenic cells, released after physical exertion, could be a key factor in exercise-induced bone formation.

INTRODUCTION

The aim of our research was to explore if a weight-bearing and resistance exercise program could positively affect circulating osteogenic cells (OCs), markers of bone formation and quality of life (QoL) in osteopenic postmenopausal women.

METHODS

We recruited 33 postmenopausal women with a T-score at lumbar spine or femoral neck between - 1 and - 2.5 SD. Anthropometric and fitness parameters, bone-remodeling markers, OCs, and QoL were evaluated at the time of enrolment, after 1-month run-in period, and after 3 months of weight-bearing and resistance exercise.

RESULTS

After 3 months of training, the pro-collagen type 1 N-terminal peptide (P1NP) and the number of OCs were significantly increased, with no significant increase of the type 1 collagen cross-linked C-telopeptide (sCTX). We also observed a significant increase in body height, one-repetition maximum (1RM) on the pull-down lat machine and leg press, and mean VO₂max. The increase of immature circulating OCs was significantly correlated with the improvement of 1RM both of the upper and lower limbs. Moreover, QoL was significantly improved with regard to pain, physical function, mental function, and general QoL. The improvement in QoL, namely in the overall score and in the pain score, was significantly correlated with the increase in height.

CONCLUSIONS

The exercise program we trialed is able to increase the markers of bone formation and the commitment of immature OCs with no significant increase in the markers of bone resorption. Our results confirm that combined weight-bearing and resistance physical activity is an effective tool to improve QoL of postmenopausal women with low bone mass.

TRIAL REGISTRATION

NCT03195517.

Effects of physical activity on children's growth

OBJECTIVE

To describe the current scientific knowledge on the effects of physical exercise on the growth of children and adolescents since intrauterine life.

SOURCE OF DATA

A search was carried out in the Medline, Embase, Scielo, and Cochrane databases of studies published from 1990 to 2018. The authors included studies with different designs: clinical trials, cohort, cross-sectional and review studies.

SYNTHESIS OF DATA

Studies that addressed the subject of physical exercise or physical activity, and weight-height growth or bone or muscle tissue growth were identified. These studies were analyzed, classified, and presented by age group: fetuses, preterm newborns, preschoolers, schoolchildren, and adolescents. It was observed that almost all studies indicated the safety of physical exercises, of mild to moderate intensity, for pregnant women, as well as children and adolescents, including both aerobic and anaerobic exercises. The retrieve studies did not demonstrate that the practice of physical exercises or certain sports, especially basketball and floor gymnastics, influenced the linear growth of children or adolescents. Some studies showed an increase in bone and muscle tissue growth in child and adolescent athletes.

CONCLUSIONS

Despite the small number of studies with adequate methodology, especially randomized clinical trials, evidence appears to indicate that physical exercise is safe for both the pregnant woman and the child, from fetal life to adolescence. Physical exercise does not appear to impair the child's linear growth and contributes to the ideal shaping of bone and muscle tissues, ensuring possible beneficial effects throughout life.

Physical Activity Across Adulthood and Bone Health in Later Life: The 1946 British Birth Cohort

Leisure-time physical activity (LTPA) is widely recommended for the prevention of osteoporosis and fractures in older populations. However, whether the beneficial effects of LTPA on bone accumulate across life and are maintained even after reduction or cessation of regular PA in later life is unknown. We examined whether LTPA across adulthood was cumulatively associated with volumetric and areal bone mineral density (vBMD, aBMD) at ages 60 to 64 and whether associations were mediated by lean mass. Up to 1498 participants from the Medical Research Council National Survey of Health and Development were included in analyses. LTPA was self-reported at ages 36, 43, 53, and 60 to 64, and responses summed to generate a cumulative score (range 0 = inactive at all four ages to 8 = most active at all four ages). Total and trabecular vBMD were measured at the distal radius using pQCT and aBMD at the total hip and lumbar spine (L1 to L4) using DXA. Linear regression was used to test associations of the cumulative LTPA score with each bone outcome. After adjustment for height and weight, a 1-unit increase in LTPA score (95% CI) in men was associated with differences of 1.55% (0.78% to 2.31%) in radial trabecular vBMD, 0.83% (0.41% to 1.25%) in total hip aBMD, and 0.97% (0.44% to 1.49%) in spine aBMD. Among women, positive associations were seen for radial trabecular vBMD and total hip aBMD, but only among those of greater weight (LTPA × weight interaction p ≤ 0.01). In men, there was evidence to suggest that lean mass index may partly mediate these associations. These findings suggest that there are cumulative benefits of LTPA across adulthood on BMD in early old age, especially among men. The finding of weaker associations among women suggests that promotion of specifıc types of LTPA may be needed to benefit bone health in women. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals, Inc.

Injury epidemiology and risk factors in competitive artistic gymnasts: a systematic review

Background

Artistic gymnastics is reported to have some of the highest injury rates in sports, which limits participation and often involves considerable medical expenses.

Purpose

To critically appraise the epidemiological literature on injury patterns and risk factors in competitive artistic gymnastics.

Study design

Systematic review.

Methods

Six databases were searched for articles that investigated injuries in competitive artistic gymnasts. Injury incidence, prevalence and risk factor data were extracted, alongside information on injury location, type, severity, nature and mechanism of injury. Quality and level of evidence were assessed using a modified Downs and Black quality index checklist and the Oxford Centre for Evidence-based Medicine guidelines.

Results

The search identified 894 articles, with 22 eligible for inclusion. Descriptive analysis showed that injury incidence and prevalence varied from 0.3 to 3.6 injuries per gymnast (female=0.3–3.6, male=0.7) and 2.0–2.3 (female=2.0–2.3, male=2.0), respectively. Male gymnasts sustained mostly upper limb injuries, while female gymnast reported lower limb injuries. Floor was associated with the greatest number of injuries for both male and female gymnasts. Higher competitive level and exposure to competition were risk factors for gymnastics injury: age, body mass, body size, training duration and life stress were significant associated factors.

Conclusion

Injury incidence and prevalence results are substantial among artistic gymnasts of all competitive levels. Gymnasts who train at highly competitive levels and are exposed to competition environments are a greater risk of injury. Future researchers should implement consistent reporting methods.

How do muscle and bone strengthening and balance activities (MBSBA) vary across the life course, and are there particular ages where MBSBA are most important?

This narrative review focuses on the role of strength and balance activities throughout the lifecycle to improve physical capacity and reduce all-cause mortality. The evidence suggests strong associations in middle and older age, with poor balance, poor strength or poor physical function having strong associations with mortality. Currently in the UK, the proportions of adults (69% of men and 76% of women) not meeting the strength and balance guidelines (of 2 or more sessions/week) is concerning. This report identifies specific time points in the lifecycle where specific promotion of and engagement with strength and balance activities would be most beneficial for health: 18-24y to maximize bone and muscle mass gains, 40-50y to maintain strength and reduce that downward cycle, and over 65s to preserve balance and strength and maintain independence). This review also suggests specific transition points/events in life where there may be an increase in sedentary behaviour or loss of muscle function (pregnancy, menopause, onset of on diagnosis of disease, retirement, on becoming a carer and following hospitalization), where it would be useful to initiate additional strength and balance exercises to improve future health outcomes.

Are consumption of dairy products and physical activity independently related to bone mineral density of 6-year-old children? Longitudinal and cross-sectional analyses in a birth cohort from Brazil

OBJECTIVE

To evaluate cross-sectional and longitudinal associations of consumption of dairy products and physical activity (PA) with bone mineral density (BMD).

DESIGN

Cohort study with children from the 2004 Pelotas (Brazil) Birth Cohort.

SETTING

Pelotas, a medium-sized Brazilian city.

SUBJECTS

The study started in 2004 and mothers/children were interviewed/measured periodically from birth to age 6 years. PA was measured by maternal proxy at 4 and 6 years and by accelerometry at 6 years. Consumption of dairy products was measured using 24 h food recall (at 4 years) and FFQ (at 6 years). Total-body and lumbar-spine BMD (g/cm2) were measured by dual-energy X-ray absorptiometry.

RESULTS

At 6 years, BMD was measured in 3444 children and 2636 children provided data on objectively measured PA by accelerometry. Consumption of dairy products at 4 years was associated with higher lumbar-spine BMD at 6 years in boys, while current consumption was positively associated with BMD in both sexes (P < 0·001). PA assessed by maternal report at 4 and 6 years of age was associated with higher BMD at 6 years in boys. PA assessed by accelerometry was positively related to total-body and lumbar-spine BMD in boys and lumbar-spine BMD in girls. We did not find evidence for an interaction between PA and consumption of dairy products on BMD.

CONCLUSIONS

We observed positive and independent longitudinal and cross-sectional associations between consumption of dairy products and PA with BMD in the total body and at the lumbar spine in young children.

Track and Field Practice and Bone Outcomes among Adolescents: A Pilot Study (ABCD-Growth Study)

Background

Osteoporosis is considered a public health problem with high worldwide prevalence. One approach to prevention is through the promotion of physical activity, especially exercise, during adolescence.

Methods

This study compared bone variables in different body segments in adolescents according to participation in track and field. The study included 34 adolescents (22 boys), of whom 17 were track and field athletes and 17 were control subjects. Bone mineral density (BMD, g/cm²) and bone mineral content (BMC, g) were analyzed using dual energy X-ray absorptiometry (total body stratified by body segments). Peak height velocity was used to estimate somatic maturation.

Results

Athletes had higher BMD (P=0.003) and BMC (P=0.011) values in the lower limbs and higher whole body BMD (P=0.025) than the control group. However, when adjusted for confounding factors, the difference was not maintained. The groups had similar lean soft tissue values (P=0.094). Training overload was positively correlated with BMD in the upper limbs (r=0.504; 95% confidence interval, 0.031-0.793). Although track and field athletes had higher BMD and BMC values in the lower limbs, these differences were not significant when adjusted for confounding factors.

Conclusions

Track and field participation in adolescence appears to influence BMD and BMC in lower limbs, and fat-free mass seems to mediate this effect. Also, higher training loads were found to be positive for bone health in upper limbs.

Bone adaptation in response to treadmill exercise in young and adult mice

Exercise is a key determinate of fracture risk and provides a clinical means to promote bone formation. However, the efficacy of exercise to increase bone mass declines with age. The purpose of this study was to identify age-related differences in the anabolic response to exercise at the cellular and tissue level. To this end, young (8-weeks of age) and adult (36-weeks of age) male mice were subjected to a moderate exercise regimen of running on a treadmill. As a result, exercise had a significant effect on PTHrP and SOST gene expression during the first week that was dependent upon age. In particular, young mice displayed an increase in PTHrP expression and decrease in SOST expression, both of which remained unaffected by exercise in the adult mice. After 5-weeks of exercise, a significant decrease in the percentage of osteocytes expressing sclerostin at the protein level was found in young mice, but not adult mice. Mechanical testing of the tibia found exercise to have a significant influence on tissue-level mechanical properties, specifically ultimate-stress and modulus that was dependent on age. Adult mice in particular experienced a significant decrease in modulus despite an increase in cortical area and cortical thickness compared to sedentary controls. Altogether, this study demonstrates a shift in the cellular response to exercise with age, and that gains in bone mass at the adult stage fail to improve bone strength.

Physical Activity in Adolescents and Young Adults with Cerebral Palsy

The aim of this study was to examine the level of physical activity in adults with cerebral palsy (CP) and to analyse its relationship with physical activity as adolescents, pain, and gross motor function. A prospective cohort study was performed using data from the Swedish National CP Registry (CPUP) for all 129 individuals born in 1991–1993 living in Skåne and Blekinge who reported to CPUP at 14–16 years of age. Physical activity as adult was analysed relative to physical activity as adolescents, pain, and the Gross Motor Function Classification System (GMFCS). Seventy-one individuals at GMFCS I–V were followed up as adults and included in the analyses. Of these, 65% were physically active, but only 56% performed physical activity at least once a week. Their physical activity as adults differed relative to their physical activity as adolescents (p = 0.011) but not to pain or GMFCS. Being physically active as an adolescent doubled the probability of being active as an adult (OR 2.1; p = 0.054), indicating that physical activity in adults with CP is related to their physical activity as adolescents. Therefore, interventions to increase physical activity among adolescents with CP are likely also to improve physical activity in adulthood.

High-impact exercise in adulthood and vertebral dimensions in midlife - the Northern Finland Birth Cohort 1966 study

Background

Vertebral size and especially cross-sectional area (CSA) are independently associated with vertebral fracture risk. Previous studies have suggested that physical activity and especially high-impact exercise may affect vertebral strength. We aimed to investigate the association between high-impact exercise at 31 and 46 years of age and vertebral dimensions in midlife.

Methods

We used a subsample of 1023 individuals from the Northern Finland Birth Cohort 1966 study with records of self-reported sports participation from 31 and 46 years and MRI-derived data on vertebral dimensions from 46 years. Based on the sports participation data, we constructed three impact categories (high, mixed, low) that represented longitudinal high-impact exercise activity in adulthood. We used linear regression and generalized estimating equation (GEE) models to analyse the association between high-impact exercise and vertebral CSA, with adjustments for vertebral height and body mass index.

Results

Participation in high-impact sports was associated with large vertebral CSA among women but not men. The women in the 'mixed' group had 36.8 (95% confidence interval 11.2–62.5) mm² larger CSA and the women in the 'high' group 43.2 (15.2–71.1) mm² larger CSA than the 'low' group.

Conclusions

We suggest that participation (≥ 1/week) in one or more high-impact sports in adulthood is associated with larger vertebral size, and thus increased vertebral strength, among middle-aged women.

The Impact of Training Load on Bone Mineral Density of Adolescent Swimmers: A Structural Equation Modeling Approach

PURPOSE

To investigate the mediating effect of muscle mass on the relationship between training load and bone density in adolescent swimmers.

METHODS

A cross-sectional study involving 87 control and 22 swimmers aged 10-19 years (overall sample: n = 109). Swimmers had a minimum of 1 year of competition in regional and national championships, and control adolescents reported 1 year without any organized sport. Bone density was the main outcome (dual-energy X-ray absorptiometry), which was measured in upper limbs, lower limbs, spine, and whole body. Monthly training load was the independent variable, while the mediation effect of lean soft tissue was assessed. Maturity offset, age, inflammation, and vitamin D intake were treated as covariates.

RESULTS

Swimmers had lower bone density than controls; there was a significant and positive relationship between training load and muscle mass. In boys, training load presented a negative correlation with bone density in lower limbs [r = -.293; 95% confidence interval (CI), -.553 to -.034]. In girls, training load was negatively related to bone mineral density in lower limbs (r = .563; 95% CI, -.770 to -.356) and whole body (r = -.409; 95% CI, -.609 to -.209).

CONCLUSION

Training load had a negative relationship on bone density of swimmers of both sexes, independently of the positive effect of lean soft tissue on bone density.

Factors Associated with Bone Health in Malaysian Middle-Aged and Elderly Women Assessed via Quantitative Ultrasound

Risk factors for osteoporosis may vary according to different populations. We aimed to investigate the relationship between risk factors of osteoporosis and bone health indices determined via calcaneal quantitative ultrasound (QUS) in a group of Malaysian women aged 50 years or above. A cross-sectional study was performed on 344 Malaysian women recruited from a tertiary medical centre in Kuala Lumpur, Malaysia. They answered a self-administered questionnaire on their social-demographic details, medical history, lifestyle, and physical activity status. Their height was measured using a stadiometer, and their body composition estimated using a bioelectrical impedance device. Their bone health status was determined using a water-based calcaneal QUS device that generated three indices, namely speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness index (SI). A T-score was computed from SI values using a reference database from a mainland Chinese population. Women with three or more lifetime pregnancies, who were underweight and not drinking coffee had a significantly lower BUA. Stepwise multiple linear regression showed that SOS was predicted by age alone, BUA and SI by years since menopause, body mass index (BMI), and number of lifetime pregnancies, and T-score by years since menopause and percentage of body fat. As a conclusion, suboptimal bone health in middle-aged and elderly Malaysian women as indicated by QUS is associated with old age, being underweight, having a high body fat percentage, and a high number of lifetime pregnancies. Women having several risk factors should be monitored more closely to protect their bones against accelerated bone loss.