title: Associations between leisure physical activity participation and cortical bone mass and geometry at the radius and tibia in a Canadian cohort of postmenopausal women.
abstract: Few studies have examined the effects of leisure physical activity (PA) participation on bone mass and geometry in postmenopausal women using peripheral quantitative computed tomography (pQCT). The purpose of this study was to determine associations between leisure PA participation and bone mass and geometry at the radius and tibia in a Canadian cohort of healthy postmenopausal women (n=234, mean age 62 years). Leisure PA participation was assessed using the Minnesota Leisure Time Physical Activity Questionnaire and by generating a total activity score (TAS, mean=105, range=0-840). Bone mass and geometry at the distal and midshaft sites of the non-dominant radius and tibia were measured using pQCT. Associations between TAS and bone mass and geometry variables were determined using linear regression models adjusted for clinically relevant confounding variables. TAS was positively and significantly associated with total content, total area, cortical content and cortical area at the midshaft sites of the radius and tibia (p<0.05 for all associations). TAS was also positively and significantly associated with bone bending and torsional strength parameters at the midshaft radius and tibia (p<0.05 for all associations). No associations were observed between TAS and trabecular bone parameters. Leisure PA participation is positively associated with cortical bone mass and geometry as well as bending and torsional strength at weight-bearing and non-weight-bearing bone sites and may have the potential to modify bone strength and influence bone fragility in postmenopausal women.
authors.affiliation: University of Toronto, Toronto ON, Canada. celeste.hamilton@utoronto.ca
authors.forename: Celeste J
authors.initials: CJ
authors.lastname: Hamilton
authors.forename: Scott G
authors.initials: SG
authors.lastname: Thomas
authors.forename: Sophie A
authors.initials: SA
authors.lastname: Jamal
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density / Q000502:physiology*; D002170:Canada; D015331:Cohort Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007899:Leisure Activities; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D017698:Postmenopause / Q000502:physiology*; D011884:Radius / Q000033:anatomy & histology* / Q000502:physiology; D013977:Tibia / Q000033:anatomy & histology* / Q000502:physiology