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Abstract ObjectivesVariation in trabecular and cortical bone properties is often used to infer habitual behavior in the past. However, the structures of both types of bone are rarely considered together and may even contradict each other in functional interpretations. We examine trabecular and cortical bone properties in various athletes and sedentary controls to clarify the associations between combinations of cortical and trabecular bone properties and various loading modalities. Materials and methodsWe compare trabecular and cortical bone properties using peripheral quantitative computed tomography scans of the tibia between groups of 83 male athletes (running, hockey, swimming, cricket) and sedentary controls using Bayesian multilevel models. We quantify midshaft cortical bone rigidity and area (J, CA), midshaft shape index (Imax/Imin), and mean trabecular bone mineral density (BMD) in the distal tibia. ResultsAll groups show unique combinations of biomechanical properties. Cortical bone rigidity is high in sports that involve impact loading (cricket, running, hockey) and low in nonimpact loaded swimmers and controls. Runners have more anteroposteriorly elliptical midshafts compared to other groups. Interestingly, all athletes have greater trabecular BMD compared to controls, but do not differ credibly among each other. DiscussionResults suggest that cortical midshaft hypertrophy is associated with impact loading while trabecular BMD is positively associated with both impact and nonimpact loading. Midshaft shape is associated with directionality of loading. Individuals from the different categories overlap substantially, but group means differ credibly, suggesting that nuanced group‐level inferences of habitual behavior are possible when combinations of trabecular and cortical bone are analyzed.
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Bone density and frame size in adult women: Effects of body size, habitual use, and life history
Abstract ObjectiveBone mineral density (BMD) and frame size are important predictors of future bone health, with smaller frame size and lower BMD associated with higher risk of later fragility fractures. We test the effects of body size, habitual use, and life history on frame size and cortical BMD of the radius and tibia in sample of healthy adult premenopausal women. MethodsWe used anthropometry and life history data from 123 women (age 18‐46) from rural Poland. Standard techniques were used to measure height, weight, and body fat. Life history factors were recorded using surveys. Grip strength was measured as a proxy for habitual activity, wrist breadth for skeletal frame size. Cortical BMD was measured at the one‐third distal point of the radius and mid‐point of the tibia using quantitative ultrasound (reported as speed of sound, SoS). ResultsRadial SoS was high (meant‐score 3.2 ± 1.6), but tibia SoS was average (meant‐score 0.35 ± 1.17). SoS was not associated with age, although wrist breadth was positively associated with age after adjusting for height. Radius SoS was not associated with measures of body size, habitual use, or life history factors. Wrist breadth was associated with body size (p < .05 for all), lean mass, and grip strength. Tibia SoS was associated with height. Life history factors were not associated with frame size or cortical SoS. ConclusionsHabitual use and overall body size are more strongly associated with frame size and cortical SoS than life history factors in this sample of healthy adult women.
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- Award ID(s):
- 1650839
- PAR ID:
- 10451024
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- American Journal of Human Biology
- Volume:
- 33
- Issue:
- 2
- ISSN:
- 1042-0533
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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