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Innov Aging
Innov Aging
innovateage
Innovation in Aging
2399-5300 Oxford University Press US 

10.1093/geroni/igaa057.2740
igaa057.2740
Abstracts
Session 7070 (Symposium)
AcademicSubjects/SOC02600
Effects of Daily Vitamin D Supplementation on Objectively Measured Physical Activity: Results From the STURDY Trial
Schrack Jennifer 1 Urbanek Jacek 2 Wanigatunga Amal 1 Juraschek Stephen 3 Mitchell Christine 1 Michos Erin 4 Roth David 2 Appel Lawrence 5 1 
Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States
2 
Johns Hopkins University, Baltimore, Maryland, United States
3 
Harvard Medical School, Boston, Massachusetts, United States
4 
Johns Hopkins School of Medicine, Baltimore, Maryland, United States
5 
Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
2020 
16 12 2020 
16 12 2020 
4 Suppl 1 Program Abstracts from The GSA 2020 Annual Scientific Meeting “Turning 75: Why Age Matters”760 760
© The Author(s) 2020. Published by Oxford University Press on behalf of The Gerontological Society of America.2020This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.Abstract
Cross-sectional evidence suggests older adults with higher serum vitamin D are more physically active, but whether long-term vitamin D supplementation attenuates age-related declines in physical activity (PA) is undefined. We examined the association between vitamin D supplementation and daily PA in 639 STURDY participants (aged 77 (5.4) years; 44% women) over up to 24-months. Participants were randomized to receive 200 (n=275), 1000 (n=168), 2000 (n=59), or 4000 (n=63) IU/day of vitamin D3. PA was measured using the Actigraph Link wrist-worn accelerometer 24 hours/day for 7-days at baseline, 3, 12, and 24 months. In linear mixed models adjusted for baseline PA level, total daily PA appeared to decline (β=-43.3 counts, p=0.06) annually for all groups and there was no difference by vitamin D3 dose (p for group*time =0.14). These results suggest daily vitamin D supplementation has no effect on quantities of daily PA.