ArticleAmerican journal of epidemiology2008
Frequency of leisure-time physical activity and serum 25-hydroxyvitamin D levels in the US population: results from the Third National Health and Nutrition Examination Survey.
Article in American journal of epidemiology, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 96 papers, 1 of them a synthesis that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
96 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Physical activity, cardiorespiratory fitness and risk of cutaneous malignant melanoma: Systematic review and meta-analysis.PloS one · 2018Pooled it
- The association of vitamin D supplementation and serum vitamin D levels with physical activity in older adults: Results from a randomized trial.Journal of the American Geriatrics Society · 2023Trial
- Vitamin D Deficient Older Adults Are More Prone to Have Metabolic Syndrome, but Not to a Greater Number of Metabolic Syndrome Parameters.Nutrients · 2020Trial
- The effect of an exercise program in pregnancy on vitamin D status among healthy, pregnant Norwegian women: a randomized controlled trial.BMC pregnancy and childbirth · 2019Trial
- Effects of chronic endurance exercise training on serum 25(OH)D concentrations in elderly Japanese men.Endocrine · 2018Trial
- Vitamin D, parathyroid hormone and metabolic syndrome - the PORMETS study.BMC endocrine disorders · 2017Trial
- The Effect of a 12-Week Health Training Program on Selected Anthropometric and Biochemical Variables in Middle-Aged Women.BioMed research international · 2017Trial
- Trial
- Trial
- The Importance of Vitamin D and Magnesium in Athletes.Nutrients · 2025Review
- Vitamin D nutritional status and the influencing factors among children and adolescents.Frontiers in public health · 2025Article
- Secular trends of vitamin D and calcium intake and their circulating levels in US adults from 2007 to 2018.Frontiers in nutrition · 2025Article
- Article
- Associations of Serum Vitamin D Concentration with Cardiovascular Risk Factors and the Healthy Lifestyle Score.Nutrients · 2023Article
- Vitamin D level regulates serum lipids discrepantly in adults with and without dyslipidemia.Endocrine connections · 2023Article
- Diet, physical activity, and UV protection comprehensively influenced vitamin D status in college students: a cross-section study from China.Journal of health, population, and nutrition · 2023Article
- Mediation of BMI on 25-Hydroxyvitamin D Levels in U.S. Adults with Sugar-Sweetened Beverages Consumption.Nutrients · 2023Article
- Insulin Resistance and Vitamin D Deficiency: A Link Beyond the Appearances.Frontiers in cardiovascular medicine · 2022Review
- The Role of Vitamin D in Early Knee Osteoarthritis and Its Relationship with Their Physical and Psychological Status.Nutrients · 2021Article
- Exercise Training: The Holistic Approach in Cardiovascular Prevention.High blood pressure & cardiovascular prevention : the official journal of the Italian Society of Hypertension · 2021Review
36 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
2 authors.
Funding
Abstract
The decline in vitamin D status among older people is probably due to decreased synthesis of vitamin D by sun-exposed skin and/or decreased outdoor activity. The authors examined the association between outdoor leisure physical activity and serum 25-hydroxyvitamin D in the Third National Health and Nutrition Examination Survey (1988-1994) (n = 15,148 aged >/=20 years). The mean 25-hydroxyvitamin D concentration declined with increasing age, with 79, 73, and 68 nmol/liter for persons aged 20-39, 40-59, and 60 or more years. The proportion that engaged in outdoor activity in the past month was 80% for persons aged 20-39 and 40-59 years but 71% for those aged 60 or more years. In contrast, the mean difference in 25-hydroxyvitamin D between those who participated in outdoor activities daily compared with those who did not participate in the past month was similar for the youngest and oldest age groups: 13 and 16 nmol/liter, respectively. Those persons aged 60 or more years who participated in daily outdoor activities had a mean 25-hydroxyvitamin D concentration similar to that of persons aged 20-39 years: 77 versus 79 nmol/liter, respectively. These nationally representative data suggest that persons aged 60 or more years can synthesize enough vitamin D from daily outdoor activities to maintain vitamin D levels similar to those of young adults.
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