3-year follow-up results of bone mineral content and density after a school-based physical activity randomized intervention trial

This follow-up study confirms our previous findings that the ER-α PvuII polymorphism (Pp) modulates the association between exercise and bone mass. The differences in bone properties of girls with consistently low physical activity (LLPA) and consistently high physical activity (HHPA) were evident only in those bearing the heterozygote ER-α genotype (Pp). In particular, areal bone mineral density of the total femur, bone mineral content and areal bone mineral density of the femoral neck, and bone mineral content and cortical thickness of the tibia shaft were significantly (p < .05) lower in the Pp girls with LLPA than in their HHPA counterparts. These findings might partly explain the genetic basis of human variation associated with exercise training.

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The Positive Relationship between Moderate-to-Vigorous Physical Activity and Bone Mineral Content Is Not Mediated by Free Leptin Index in Prepubertal Children: The PANIC Study

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18105365 ◽

2021 ◽

Vol 18 (10) ◽

pp. 5365

Author(s):

Annie M. Constable ◽

Josie E. Porter ◽

Danielle Benger ◽

Dimitris Vlachopoulos ◽

Alan R. Barker ◽

...

Keyword(s):

Physical Activity ◽

Bone Mineral Content ◽

Bone Mineral ◽

Mineral Content ◽

Vigorous Physical Activity ◽

Normal Weight ◽

Cross Sectional ◽

Prepubertal Children ◽

Total Body ◽

The Relationship

Purpose: Moderate-to-vigorous physical activity (MVPA) positively influences bone mineral content (BMC) in prepubertal children, but it is unknown whether this relationship is partially mediated by free leptin index. The aim of this study was to examine whether the relationship between MVPA and total body less head (TBLH) BMC is mediated or moderated by free leptin index in prepubertal children. Methods: We performed a cross-sectional analysis on 401 children (194 girls) from baseline examinations of the Physical Activity and Nutrition in Childhood Study. We applied the four-way decomposition mediation analysis method to assess whether free leptin index, measured from fasted blood samples, mediated the relationship between accelerometer-measured MVPA and TBLH BMC measured by dual-energy X-ray absorptiometry. Results: MVPA had a positive controlled direct effect on TBLH BMC in girls and boys (β = 0.010 to 0.011, p < 0.05). There was no mediation or interaction between MVPA, free leptin index and TBLH BMC in girls or boys (β = −0.000 to 0.001, p > 0.05). Conclusion: Our study indicates that MVPA positively influences TBLH BMC through pathways not related to free leptin index in predominantly normal-weight prepubertal children, likely primarily through mechanical loading. The relationships between MVPA, free leptin index and TBLH BMC may be influenced by other factors such as pubertal status and adiposity, so it is unknown whether these observations extend to overweight and obese children at different stages of puberty.

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Influence of Physical Activity on Bone Mineral Content and Density in Overweight and Obese Children with Low Adherence to the Mediterranean Dietary Pattern

Nutrients ◽

10.3390/nu10081075 ◽

2018 ◽

Vol 10 (8) ◽

pp. 1075 ◽

Cited By ~ 3

Author(s):

Victoria Muñoz-Hernandez ◽

Lide Arenaza ◽

Luis Gracia-Marco ◽

Maria Medrano ◽

Elisa Merchan Ramirez ◽

...

Keyword(s):

Physical Activity ◽

Bone Mineral Content ◽

Bone Mineral ◽

Dietary Pattern ◽

Mineral Content ◽

Overweight And Obesity ◽

Moderate Intensity ◽

Obese Children ◽

Mediterranean Dietary Pattern ◽

The Mediterranean

The objective of the present cross-sectional study was to examine the associations of physical activity and the adherence to the Mediterranean dietary pattern (MDP) with bone mineral content (BMC) and density (BMD) in children with overweight and obesity. A total of 177 (n = 80 girls) children with overweight and obesity aged 8 to 12 years old participated in the study. Both BMC and BMD were assessed by Dual-Energy X-ray absorptiometry. Dietary patterns were assessed by the KIDMED questionnaire and two 24-hour recalls. Physical activity was assessed by accelerometers for 7 consecutive days (24 hours/day). Low adherence to the MDP was observed in 82.4% of participants. Higher physical activity levels (of at least moderate intensity) and lower sedentary time were significantly associated with BMC and BMD in children with low adherence to the MDP (all p < 0.05). No associations were observed between physical activity and BMC and BMD in children with high adherence to the MDP. In conclusion, engaging in moderate to vigorous physical activity and reducing the time spent in sedentary behavior might be particularly beneficial for improving bone health in overweight or obese children with poor adherence to the Mediterranean dietary pattern.

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Sodium loading, treadmill walking, and the acute redistribution of bone mineral content on dual energy X-ray absorptiometry scans

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00227.2018 ◽

2019 ◽

Vol 316 (1) ◽

pp. R59-R67

Author(s):

Tamara Hew-Butler ◽

Kailyn Angelakos ◽

Joshua Szczepanski

Keyword(s):

Bone Mineral Content ◽

Bone Mineral ◽

Mineral Content ◽

Dual Energy ◽

Treadmill Walking ◽

Primary Study ◽

Intervention Trial ◽

Dxa Scan ◽

X Ray ◽

Total Body

The purpose of this study was to assess relationships between plasma sodium concentration ([Na+]) and bone mineral content (BMC) after an acute sodium load plus treadmill walking and then quantify the amount of sodium the dual energy X-ray absorptiometry (DXA) scan could detect. The primary study was a single-blind randomized control crossover trial under two conditions: ingestion of six flour tablets (placebo trial) or six 1-g NaCl tablets (salt intervention trial). The tablets were ingested after baseline blood and urine collection followed immediately by the DXA scan. After 60 min of rest, a 45-min treadmill walk was conducted. Immediately postexercise, blood and urine were collected and the DXA scan was repeated. Main outcomes included changes (∆: post minus pre) in plasma [Na+] and BMC. Additionally, six 1-g NaCl tablets were superimposed over a DXA spine phantom for separate quantification of sodium as BMC. Fourteen subjects completed the primary study. Two-way repeated measures ANOVA tests revealed significant interaction ( F = 13.06; P = 0.0007), condition ( F = 21.88; P < 0.001), and time ( F = 6.51; P = 0.014) effects in plasma [Na+]. A significant condition ( F = 6.46; P = 0.014) effect was also noted in urine [Na+]. Total body BMC∆ was negatively correlated with plasma [Na+]∆ ( r = −0.43; P = 0.02) and urine [Na+]∆ ( r = −0.47; P = 0.01). Total body BMC∆ in the salt intervention trial [−5.5 (27) g] closely approximated the amount of NaCl ingested and subsequently absorbed into the bloodstream. The DXA scan quantified 67% of NaCl tablets as BMC in spine phantom analyses. Total body BMC∆ was negatively related to plasma and urine [Na+]∆ after treadmill walking. Reductions in total body BMC closely approximated the amount of NaCl ingested (~6 g). The DXA scan quantified NaCl as BMC.

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