Impact loading exercise induced osteogenesis from childhood to early adulthood in tennis players aged 8-30 years

Osteogenesis with impact-loading exercise is often assessed by the extra bone growth induced in the loaded arm of tennis players. We used PRISMA to explore % bone mineral content (BMC) and area (BA) asymmetry in players 8-30 years according to weekly training hours, age, sex, maturity, and bone segment. Proper statistics for 70 groups were extracted by two reviewers from 18 eligible studies of low risk of bias (< 35, STROBE) and good quality (> 70%). The quality of the review was high (AMSTAR, 81%). Using "random effects" we tested moderation-specific meta-comparisons and meta-regressions. The loaded bones % hypertrophy was higher in BMC (19%) than BA (10%), and, with BMC and BA merged, in boys (17%) than girls (13%), in humerus (19%) than radius-ulna (14%), and in pubertal (19%) players. Weekly training hours were more important (43%) than sex (17%), puberty (14%) and bone (15%) in BMC, and puberty (48%) was more important than weekly training hours (19%), sex (12%), and radius-ulna (5%) in BA. The loaded bones % hypertrophy correlated with weekly training hours highly (> 0.60) in all maturity groups for BMC and BA, and moderately (0.41) in early adults for BA; it also correlated with age (≥ 0.60) in children and peripubertal players, but not (0.037) with starting age. Impact loading exercise favors mineralization twice than bone expansion, while puberty favors bone expansion about three times more than mineralization. The bone gains are higher for boys than girls, and for peripubertal than older players. The bone growth implications are discussed considering limitations and future research.

Association of daily physical activity and bone microarchitecture in young adults with type 1 diabetes - A pilot exploratory study

Purpose

Physical activity (PA) is an important determinant of skeletal health. In young adults with type 1 diabetes (T1D) fracture risk is increased, yet few studies have examined the PA and bone health relationship. Therefore, this pilot cross-sectional study characterized PA levels and their association with bone parameters measured by high resolution peripheral quantitative computed tomography (HR-pQCT) in young adults with T1D.

Methods

HR-pQCT (Xtreme CTII) was used to measure bone outcomes at the distal tibia and radius, and accelerometery (ActiGraph GT3X) recorded daily minutes of light and moderate-vigorous physical activity (MVPA). Quadratic regression analyses were conducted with a p-value ≤ 0.05 considered significant.

Results

PA data from 19 young adults (23.1 ± 1.9 years) with T1D was analyzed. Over half (63 %) of participants completed ≥150 min of MVPA per week, however, most measured activity time per day (57 %) was spent in sedentary pursuits. Significant non-linear associations were found between the duration of MVPA and several trabecular bone parameters at the tibia.

Conclusions

In young adults with T1D, MVPA may have site specific (tibia) and compartment specific (trabecular) non-linear associations with bone. Further studies should confirm these findings, which may help inform evidence-based exercise recommendations to optimize bone health in young adults with T1D.

Bone and muscle differences in children and adolescents with type 1 diabetes: The mediating role of physical activity

Children with type 1 diabetes (T1D) experience an increased risk of fracture, which may be related to altered bone development. We aimed to assess differences in bone, muscle and physical activity (PA), and explore if better muscle and PA measures would mitigate bone differences between children and adolescents with T1D and typically developing peers (TDP). We matched 56 children and adolescents with T1D (mean age 11.9 yrs) and 56 TDP (11.5 yrs) by sex and maturity from 171 participants with T1D and 66 TDP (6-17 yrs). We assessed the distal radius and tibia with high-resolution peripheral quantitative computed tomography (HR-pQCT), and the radius and tibia shaft bone and muscle with pQCT. We also measured muscle function from force-related measures in neuromuscular performance tests (push-up, grip test, countermovement and long jump). We compared PA based on questionnaire scores and accelerometers between groups. Bone, muscle, and neuromuscular performance measures were compared using MANOVA. We used mediation to explore the role of PA and muscle in bone differences. Children and adolescents with T1D had 6-10 % lower trabecular density, bone volume fraction, thickness and number at both distal radius and tibia, and 11 % higher trabecular separation at the distal radius than TDP. They also had 3-16 % higher cortical and tissue mineral density, and cortical thickness at the distal radius, 5-7 % higher cortical density and 1-3 % higher muscle density at both shaft sites compared to TDP. PA mediated the between-group difference in trabecular number (indirect effect -0.04) at the distal radius. Children and adolescents with T1D had lower trabecular bone density and deficits in trabecular micro-architecture, but higher cortical bone density and thickness at the radius and tibia compared to TDP. They engaged in less PA but had comparable muscle measures to those of TDP. PA participation may assist in mitigating deficit in trabecular number observed in children and adolescents with T1D.

Autonomous motivation, social support, and physical activity in school children: moderating effects of school-based rope skipping sports participation

Purpose

Recent studies have shown that physical activity (PA) levels are low among children and adolescents globally. In order to reverse this trend, PA interventions are increasingly favoured. The school setting is the ideal place to address the issues that many children face. The purpose of this study was to (a) The primary focus of this study is to delve into the mediating role played by school-based rope skipping sports participation (SRSP) in the connection between social support and moderate to high-intensity physical activity (MVPA) among school children. (b) Additionally, this research aims to examine the moderating effect of within this pathway.

Methods

We conducted a survey involving 721 adolescents residing in Changsha City. The participants' ages ranged from 8 to 12 years, with an average age of 9.84 ± 1.535 years. Out of these participants, 406 were boys, and 315 were girls. To assess variables such as social support and autonomous motivation, we employed standardized measurement scales. Subsequently, we analyzed the collected data using various statistical methods, including independent s-amples t-tests, bivariate correlation analysis, descriptive statistical analysis, structural equation modeling (SEM), and the Johnson-Neyman method.

Results

An independent samples t-test revealed a statistically significant difference in MVPA between genders (p = 0.003 < 0.05), with boys exhibiting a higher level of engagement in MVPA compared to girls, Correlation analysis revealed significant positive associations among several key variables. Specifically, social support demonstrated a noteworthy positive correlation with autonomous motivation (r = 0.331, p < 0.01) as well as school children's engagement in MVPA (r = 0.308, p < 0.01). Moreover, autonomous motivation displayed a significant positive correlation with school children's involvement in MVPA (r = 0.459, p < 0.01). The moderating analysis revealed a significant influence of the interaction between increased participation in and social support on school children's engagement in MVPA.

Conclusion

Social support and autonomy support have been proven effective in enhancing school children's engagement in MVPA. They exert their influence indirectly by fostering autonomous motivation. Notably, robust social support can significantly benefit MVPA school children with high activity requirements, particularly those regularly engaged in MVPA during the school day.

Recommendations for High-resolution Peripheral Quantitative Computed Tomography Assessment of Bone Density, Microarchitecture, and Strength in Pediatric Populations

PURPOSE OF REVIEW

The purpose of this review is to summarize current approaches and provide recommendations for imaging bone in pediatric populations using high-resolution peripheral quantitative computed tomography (HR-pQCT).

RECENT FINDINGS

Imaging the growing skeleton is challenging and HR-pQCT protocols are not standardized across centers. Adopting a single-imaging protocol for all studies is unrealistic; thus, we present three established protocols for HR-pQCT imaging in children and adolescents and share advantages and disadvantages of each. Limiting protocol variation will enhance the uniformity of results and increase our ability to compare study results between different research groups. We outline special cases along with tips and tricks for acquiring and processing scans to minimize motion artifacts and account for growing bone. The recommendations in this review are intended to help researchers perform HR-pQCT imaging in pediatric populations and extend our collective knowledge of bone structure, architecture, and strength during the growing years.

Relationship between Football-Specific Training Characteristics and Tibial Bone Adaptation in Male Academy Football Players

We examined the relationship between football-specific training and changes in bone structural properties across a 12-week period in 15 male football players aged 16 years (Mean ± 1 SD = 16.6 ± 0.3 years) that belonged to a professional football academy. Tibial scans were performed at 4%, 14% and 38% sites using peripheral quantitative computed tomography immediately before and 12 weeks after increased football-specific training. Training was analysed using GPS to quantify peak speed, average speed, total distance and high-speed distance. Analyses were conducted with bias-corrected and accelerated bootstrapped 95% confidence intervals (BCa 95% CI). There were increases in bone mass at the 4% (mean ∆ = 0.15 g, BCa 95% CI = 0.07, 0.26 g, g = 0.72), 14% (mean ∆ = 0.04 g, BCa 95% CI = 0.02, 0.06 g, g = 1.20), and 38% sites (mean ∆ = 0.03 g, BCa 95% CI = 0.01, 0.05 g, g = 0.61). There were increases in trabecular density (4%), (mean ∆ = 3.57 mg·cm^-3, BCa 95% CI = 0.38, 7.05 mg·cm^-3, g = 0.53), cortical dentsity (14%) (mean ∆ = 5.08 mg·cm^-3, BCa 95% CI = 0.19, 9.92 mg·cm^-3, g = 0.49), and cortical density (38%) (mean ∆ = 6.32 mg·cm^-3, BCa 95% CI = 4.31, 8.90 mg·cm^-3, g = 1.22). Polar stress strain index (mean ∆ = 50.56 mm³, BCa 95% CI = 10.52, 109.95 mm³, g = 0.41), cortical area (mean ∆ = 2.12 mm², BCa 95% CI = 0.09, 4.37 mm², g = 0.48) and thickness (mean ∆ = 0.06 mm, BCa 95% CI = 0.01, 0.13 mm, g = 0.45) increased at the 38% site. Correlations revealed positive relationships between total distance and increased cortical density (38%) (r = 0.39, BCa 95% CI = 0.02, 0.66), and between peak speed and increased trabecular density (4%) (r = 0.43, BCa 95% CI = 0.03, 0.73). There were negative correlations between total (r = -0.21, BCa 95% CI = -0.65, -0.12) and high-speed distance (r = -0.29, BCa 95% CI = -0.57, -0.24) with increased polar stress strain index (38%). Results suggest that despite football training relating to increases in bone characteristics in male academy footballers, the specific training variables promoting adaptation over a 12-week period may vary. Further studies conducted over a longer period are required to fully elucidate the time-course of how certain football-specific training characteristics influence bone structural properties.

A comparison of the associations between bone health and three different intensities of accelerometer-derived habitual physical activity in children and adolescents: a systematic review

Positive associations have been identified between bone outcomes and accelerometer-derived moderate (MPA) and vigorous (VPA) physical activity (PA) in youth; however, it remains unclear which intensity is most beneficial. This systematic review aimed to summarise accelerometer-derived methods used to estimate habitual PA in children and adolescents and determine whether the magnitude of association was consistently stronger for a particular intensity (MPA/MVPA/VPA). Observational studies assessing associations between accelerometer-derived MPA and/or MVPA and VPA with bone outcomes in children and adolescents (≤ 18 years) were identified in MEDLINE, EMBASE, Web of Science, SPORTDiscus and the Cochrane Central Register of Controlled Trials. Thirty articles were included (total n = 20,613 (10,077 males), 4-18 years). Chi-square tests determined whether the proportion of significant associations and strongest within-study associations differed significantly between intensities. Results demonstrated that accelerometer methods were highly variable between studies. Of the 570 associations analysed, 186 were significant (p < 0.05). The proportion of within-study strongest associations differed by PA intensity (3 × 2 χ2 = 86.6, p < 0.001) and was significantly higher for VPA (39%) compared to MVPA (5%; 2 × 2 χ2 = 55.3, p < 0.001) and MPA (9%, 2 × 2 χ2 = 49.1, p < 0.001). Results indicated a greater benefit of VPA over MPA/MVPA; however, variability in accelerometer-derived methods used prevents the precise bone-benefitting amount of VPA from being identified. Long epochs and numerous intensity cut-point definitions mean that bone-relevant PA has likely been missed or misclassified in this population. Future research should explore the use of shorter epochs (1 s) and identify bone-specific activity intensities, rather than using pre-defined activity classifications more relevant to cardiovascular health.

Bone health in children and youth with ASD: a systematic review and meta-analysis

Higher risk of fracture reported in individuals with autism spectrum disorder (ASD) might be linked to poor bone health and development in childhood. This study aimed to systematically review studies comparing imaged bone outcomes between children with ASD and typically developing children (TDC) or reference data, and to perform a meta-analysis comparing commonly reported bone outcomes. We searched articles published since August 2020 from PubMed, Cochrane Library, Web of Science, EMBASE, and Scopus databases. We included studies comparing areal bone mineral density (aBMD) between children with ASD and TDC in the qualitative analysis (meta-analysis), and evaluated other imaged bone outcomes qualitatively. Seven publications were identified for the systematic review, and four studies were included in the meta-analysis. The meta-analysis indicated lower aBMD at the total body (standardized mean difference = - 0.77; 95% CI, - 1.26 to - 0.28), lumbar spine (- 0.69; - 1.00 to - 0.39), total hip (- 1.00; - 1.82 to - 0.17), and femoral neck (- 1.07; - 1.54 to - 0.60) in children with ASD compared to TDC. Based on our qualitative review, limited evidence suggested 13% lower bone mineral content at the total body and 10-20% lower cortical area, cortical and trabecular thickness, and bone strength at the distal radius and tibia in children with ASD. Children with ASD have lower aBMD at the total body, lumbar spine, and hip and femoral neck compared to TDC. Limited evidence also suggests deficits in bone mineral content, micro-architecture, and strength in children with ASD.

The association between overweight and obesity on bone mineral density in 12 to 15 years old adolescents in China

Overweight/obesity can influence bone mineral accretion, but the conclusions are not consistent. We aimed to examine the association between bone mineral density (BMD) levels and body mass index (BMI) in 12 to 15 years old adolescents.We performed a cross-sectional study including 8365 adolescents. BMD was evaluated using a quantitative ultrasound device. Z scores for BMI were evaluated using World Health Organization references. Logistic regression models were performed to evaluate the association between BMD levels and BMI.Totally 1866 (22.3%) adolescents had low /reduced BMD, and boys had a higher rate than girls (72.6% vs 27.4%, P < .001). The rates of thinness, normal weight, overweight, and obesity were 2.8%, 57.1%, 22.3%, and 17.8%, respectively. The multivariable-adjusted (age, sex, systolic blood pressure, and height Z score) ORs (95% CIs) of low/reduced BMD associated with BMI groups (thinness, normal [reference], overweight, and obesity) were 0.59 (0.39-0.89), 1.00, 1.61 (1.41-1.84), and 1.98 (1.69-2.30), respectively (Ptrend < .001). This positive association existed in boys and girls though the differences were not significant between normal weight and thin girls. The multivariable-adjusted ORs for each 1-unit increase in BMI Z score were 1.36 (1.24-1.49) for girls, and 1.23 (1.16-1.30) for boys, and 1.26 (1.20-1.32) for all participants.We observed a positive association between BMI and low/reduced BMD in 12 to 15 years old adolescents. More attention should be paid on overweight and obese adolescents to reduce the risk of low BMD. Further studies are needed to explore the mechanisms of this association.

Children with Autism Spectrum Disorder Spent 30 Min Less Daily Time in Moderate-to-Vigorous Physical Activity than Typically Developing Peers: a Meta-Analysis of Cross-sectional Data

It remains unclear if participation in moderate-to-vigorous physical activity (MVPA) differs between children with ASD and typically developing children (TDC). We compared daily MVPA, time spent in MVPA during physical education (PE) and recess, and odds of not meeting MVPA recommendation (60 min/day) between children with ASD and TDC. Nine studies reporting accelerometer-measured MVPA were included in the meta-analyses. MVPA was 30 min lower/day, 12% and 8% lower during PE and recess, respectively, in children with ASD, and they had 4 times higher odds of not meeting MVPA recommendation when compared to TDC. Children with ASD engage in daily MVPA less than TDC and below the guidelines. Tailored interventions to increase MVPA in children with ASD are warranted.

Association of objectively measured physical activity and bone health in children and adolescents: a systematic review and narrative synthesis

The influence of day-to-day physical activity on bone in adolescence has not been well characterized. Forty articles were identified that assessed the relationship between accelerometry-derived physical activity and bone outcomes in adolescents. Physical activity was positively associated with bone strength in peri-pubertal males, with less consistent evidence in females. Physical activity (PA) is recommended to optimize bone development in childhood and adolescence; however, the influence of day-to-day PA on bone development is not well defined. The aim of this review was to describe the current evidence for objectively measured PA on bone outcomes in healthy children and adolescents. MEDLINE, Embase, Cochrane Library, Scopus, Web of Science, CINAHL, PsycInfo, and ClinicalTrials.gov were searched for relevant articles up to April 2020. Studies assessing the relationship between accelerometry-derived PA and bone outcomes in adolescents (6-18 years old) were included. Two reviewers independently screened studies for eligibility, extracted data, and rated study quality. Forty articles met inclusion criteria (25 cross-sectional, 15 longitudinal). There was significant heterogeneity in accelerometry methodology and bone outcomes measured. Studies in males indicated a significant, positive relationship between moderate to vigorous PA (MVPA) and bone outcomes at the hip and femur, particularly during the peri-pubertal years. The results for MVPA and bone outcomes in females were mixed. There was a paucity of longitudinal studies using pQCT and a lack of data regarding how light PA and/or impact activity influences bone outcomes. The current evidence suggests that objectively measured MVPA is positively associated with bone outcomes in children and adolescents, especially in males. However, inconsistencies in methodology make it difficult to determine the amount and type of PA that leads to favorable bone outcomes. Given that the majority of research has been conducted in Caucasian adolescents, further research is needed in minority populations.