ArticleBiomedical reports2016
Seasonal variations in vitamin D status in indoor and outdoor female athletes.
Article in Biomedical reports, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 19 papers, 2 of them syntheses that pooled it.
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Who cites it
19 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- The Prevalence of Low Vitamin D in Elite Para-Athletes: A Systematic Review.Sports medicine - open · 2024Pooled it
- Difference in Levels of Vitamin D between Indoor and Outdoor Athletes: A Systematic Review and Meta-Analysis.International journal of molecular sciences · 2023Pooled it
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- Vitamin D status and its determinants in German elite athletes.European journal of applied physiology · 2025Article
- Vitamin D and its relationship to performance and health during a competitive period in elite women's basketball and volleyball players.Physiological reports · 2025Article
- Vitamin D levels and bone mineral density of middle-aged premenopausal female football and volleyball players in Japan: a cross-sectional study.BMC sports science, medicine & rehabilitation · 2024Article
- Can the supplementation of vitamin D, sun exposure, and isolation during the COVID-19 pandemic affect the seasonal concentration of 25(OH)D and selected blood parameters among young soccer players in a one-year training season?Journal of the International Society of Sports Nutrition · 2023Article
- Nutritional Considerations for the Vegan Athlete.Advances in nutrition (Bethesda, Md.) · 2023Review
- Exploring the Relationship between Micronutrients and Athletic Performance: A Comprehensive Scientific Systematic Review of the Literature in Sports Medicine.Sports (Basel, Switzerland) · 2023Review
- Serum 25-Hydroxyvitamin D Levels in Type 2 Diabetes Patients in North China: Seasonality and the Association between Vitamin D Status and Glycosylated Hemoglobin Levels.International journal of clinical practice · 2023Article
- Vitamin D deficiency in athletes: Laboratory, clinical and field integration.Asia-Pacific journal of sports medicine, arthroscopy, rehabilitation and technology · 2022Review
- The impact of vitamin D supplementation on body fat mass in elite male collegiate athletes.Nutrition & metabolism · 2021Article
- Comparison of vitamin D sufficiency between indoor and outdoor elite male collegiate athletes.Nagoya journal of medical science · 2021Article
- Vitamin D, sport and health: a still unresolved clinical issue.Journal of endocrinological investigation · 2020Review
- 25-Hydroxyvitamin D, Vitamin D Binding Protein, Bioavailable 25-Hydroxyvitamin D, and Body Composition in a Diverse Sample of Women Collegiate Indoor Athletes.Journal of functional morphology and kinesiology · 2020Article
- Vitamin D Status Differs by Sex, Sport-Season, and Skin Pigmentation among Elite Collegiate Basketball Players.Sports (Basel, Switzerland) · 2019Article
- Predictive Factors for Vitamin D Concentrations in Swiss Athletes: A Cross-sectional Study.Sports medicine international open · 2018Article
- The Effect of Ongoing Vitamin D and Low-Fat Milk Intake on Bone Metabolism in Female High-School Endurance Runners.Journal of clinical medicine research · 2018Article
Corrections and comments
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Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Vitamin D (VD) insufficiency is a concern, particularly among young females. The VD status shows seasonal variations, since it correlates with duration of sunlight exposure. VD insufficiency in indoor athletes is therefore suggested in winter. The aim of the present study was to determine seasonal variations in VD and bone status among indoor and outdoor female athletes. The prospective study was conducted in participants aged 20-22 years old. The participants comprised of 15 indoor and 15 outdoor athletes. The biochemical markers and bone parameters were measured in March, June, September and December. The serum 25-hydroxyvitamin D (25-OH-VD) concentration showed a seasonal oscillation, with a nadir in March (indoor, 19±4.0 ng/ml; outdoor, 32±2.7 ng/ml) and a peak in September (indoor, 32±6.6 ng/ml; outdoor, 39±5.7 ng/ml). The amplitude of oscillation was greater in the indoor compared to the outdoor athletes. Seasonal variations in serum calcium exhibited a similar pattern, while the parathyroid hormone showed an inverse pattern to serum 25-OH-VD. The nadir in bone mass, measured as speed of sound, occurred in June after peaking in December among the indoor and outdoor athletes. The pattern followed 3 months after the changes in 25-OH-VD. Indoor sports athletes are more susceptible to VD insufficiency compared to outdoor sports athletes. Insufficiency is most likely to arise in winter, and could affect bone mineralization observed 3 months after.
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