CoChat
Sign Up
Cited by 45Vitamin D Research StudiesSports Performance and TrainingPhysical Activity and Health

The effects of indoor and outdoor sports participation and seasonal changes on vitamin D levels in athletes

Open access
Aydın, Canan Gönen, Dinçel, Yaşar Mahsut, Arıkan, Yavuz, Taş, Süleyman Kasım, Deniz, Serdar·2019·SAGE Open Medicine
DOI 10.1177/2050312119837480PMC PMC6415475
Open this paper in CoChat — free accountOpen PDF

Abstract

Objective: Nowadays, people tend to spend more time in the closed areas and benefit less from sunlight. In this study, we examined the results of vitamin D measurements of athletes from different disciplines in different months and aimed to determine if the synthesis of vitamin D decreases or not according to exercise environment and month. Methods: The study was conducted in participants aged 5–52 years. A total of 555 elite-level sportsmen who were admitted to our Sports Medicine Clinic in the study participated in this study. Indoor and outdoor environmental and seasonal effects on the measurements in different months were statistically evaluated. Independent-samples test and definitive statistics were used for statistical analyses and a p-value less than 0.05 has been considered significant. Results: The study group consisted of 229 male and 326 female athletes. The serum 25-hydroxyvitamin D concentration was observed; 120 (21.6%) athletes have severe serum vitamin D deficiency (<11–20 ng/mL). Vitamin D levels were not significantly different from outdoor athletes (393; 70.8%). Winter measurements of vitamin D levels were significantly lower than those measured in autumn (p = 0.000). Conclusion: Increasing vitamin D levels are very important especially in participating athletes and additional supplements are recommended whenever necessary. Gender and indoor/outdoor sports participation showed no statistically significant outcomes on vitamin D levels. However, winter season had a negative effect on vitamin D levels. Therefore, adequate precautions should be taken to increase vitamin D, especially during winter, to maintain the best performance of the athletes.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1177/2050312119837480

Cites

2 of 2 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • During the winter season, almost 60% of outdoor athletes and 64% of indoor athletes have a level of 25(OH)D <30 ng/mL.

    “It has been estimated that during the winter season, almost 60% of outdoor athletes and 64% of indoor athletes have a level of 25(OH)D <30 ng/mL, which indicates insufficiency of vitamin D [11,12,13,14,15].”

    From Influence of Sunlight and Oral D3 Supplementation on Serum 25(OH)D Concentration and Exercise Performance in Elite Soccer Players (2020) · cites this paper as [15]

    The Discussion (page unavailable) reports vitamin D deficiency in 59% of outdoor athletes and 64% of indoor athletes. It does not identify those percentages as winter-specific or explicitly define them as the proportions below 30 ng/mL. The Results report a lower mean vitamin D level in winter, but not winter-specific percentages for each group. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 29

  1. [1]McGreevy C Williams D. New insights about vitamin D and cardiovascular disease: a narrative review. Ann Intern Med 2011; 155(12): 820– 826. 22184689
  2. [2]Hochberg Z. Rickets—past and present. In: Hochberg Z (ed.) Vitamin D and rickets, vol. 6 Basel: S. Karger AG, 2003, pp. 1– 13. 12964422
  3. [3]Wharton B Bishop N. Rickets Lancet 2003; 362: 1389– 1400. 14585642
  4. [4]Mosekilde L. Vitamin D and the elderly. Clin Endocrinol 2005; 62: 265– 281. 15730407
  5. [5]Vu LH Whiteman DC van der Pols JC et al Serum vitamin D levels in office workers in a subtropical climate. Photochem Photobiol 2011; 87(3): 714– 720. 21255019
  6. [6]Van Schoor NM Lips P Worldwide vitamin D status. Best Pract Res Clin Endocrinol Metab 2011; 25(4): 671– 680. 21872807
  7. [7]Cannell JJ Hollis BW Sorenson MB et al Athletic performance and vitamin D. Med Sci Sports Exerc 2009; 41(5): 1102– 1110. 19346976
  8. [8]Combs G Jr Mahan LK Escott-Stump S. Chapter 4: vitamins. In: Gallagher MG (ed.) Krause’s food, nutrition and diet therapy. 11th ed Philadelphia, PA: Elsevier, 2004, pp. 83– 88.
  9. [10]Prabhala A Garg R Dandona P. Severe myopathy associated with vitamin D deficiency in western New York. Arch Intern Med 2000; 160(8): 1199– 1203. 10789615
  10. [11]Larson-Meyer DE Willis KS. Vitamin D and athletes. Curr Sports Med Rep 2010; 9(4): 220– 226. 20622540
  11. [13]Kucuk SC Yibar A. Nutrient value and metabolic effects of vitamin D-fortified yoghurt. Gida 2018; 43: 549– 557 (in Turkish).
  12. [14]Holick MF. Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and cardiovascular disease. Am J Clin Nutr 2004; 80(Suppl. 6): 1678S– 1688S. 15585788
  13. [15]Valtueña J González-Gross M Huybrechts I et al Factors associated with vitamin D deficiency in European adolescents: the HELENA study. J Nutr Sci Vitaminol 2013; 59(3): 161– 171. 23883686
  14. [16]Scharla SH. Prevalence of subclinical vitamin D deficiency in different European countries. Osteoporos Int 1998; 8(Suppl. 2): S7– S12. 10197176
  15. [17]Willis KS Peterson NJ Larson-Meyer DE Vitamin D status of distance runners residing in the southern United States. In: Proceedings of the SCAN’s 23rd annual symposium at the sports nutrition training camp, Austin, TX, 13–15 April 2007.
  16. [18]Morton JP Iqbal Z Drust B et al Seasonal variation in vitamin D status in professional soccer players of the English Premier League. Appl Physiol Nutr Metab 2012; 37(4): 798– 802. 22554144
  17. [20]Storlie DM Pritchett K Pritchett R et al 12-week vitamin D supplementation trial does not significantly influence seasonal 25(OH)D status in male collegiate athletes. Int J Health Nutr 2011; 2: 8– 13.
  18. [21]Halliday TM Peterson NJ Thomas JJ et al Vitamin D status relative to diet, lifestyle, injury, and illness in college athletes. Med Sci Sports Exerc 2011; 43(2): 335– 343. 20543748
  19. [22]Constantini NW Arieli R Chodick G et al High prevalence of vitamin D insufficiency in athletes and dancers. Clin J Sport Med 2010; 20(5): 368– 371. 20818195
  20. [23]Lovell G. Vitamin D status of females in an elite gymnastics program. Clin J Sport Med 2008; 18(2): 159– 161. 18332692
  21. [24]Maïmoun L Manetta J Couret I et al The intensity level of physical exercise and the bone metabolism response. Int J Sports Med 2006; 27(2): 105– 111. 16475055
  22. [25]Guillemant J Le HT Maria A et al Wintertime vitamin D deficiency in male adolescents: effect on parathyroid function and response to vitamin D3 supplements. Osteoporos Int 2001; 12(10): 875– 879. 11716192
  23. [26]Barger-Lux MJ Heaney RP. Effects of above average summer sun exposure on serum 25-hydroxyvitamin D and calcium absorption. J Clin Endocrinol Metab 2002; 87(11): 4952– 4956. 12414856
  24. [27]Valtueña J Dominguez D Til L et al High prevalence of vitamin D insufficiency among elite Spanish athletes: the importance of outdoor training adaptation. Nutr Hosp 2014; 30(1): 124– 131. 25137271
  25. [28]Walker N Love TD Baker DF et al Knowledge and attitudes to vitamin D and sun exposure in elite New Zealand athletes: a cross-sectional study. J Int Soc Sports Nutr 2014; 11(1): 47. 25253998 PMC4172920
  26. [29]Villacis D Yi A Jahn R et al Prevalence of abnormal vitamin D levels among division I NCAA athletes. Sports Health 2014; 6(4): 340– 347. 24982708 PMC4065560
  27. [30]Peeling P Fulton SK Binnie M et al Training environment and Vitamin D status in athletes. Int J Sports Med 2013; 34(3): 248– 252. 22972245
  28. [31]Thacher TD Clarke BL. Vitamin D insufficiency. Mayo Clin Proc 2011; 86(1): 50– 60. 21193656 PMC3012634
  29. [32]Hamilton B. Vitamin D and athletic performance: the potential role of muscle. Asian J Sports Med 2011; 2(4): 211– 219. 22375241 PMC3289217

Cited by

Sorted by citations

Authors
Aydın, C. G., Dinçel, Y. M., Arıkan, Y., Taş, S. K., & Deniz, S.
Affiliations
  • Department of Sports Medicine, Baltalimani Metin Sabanci Bone and Joint Diseases Education and Research Hospital, Istanbul, Turkey
  • Department of Orthopaedic and Traumatology, Baltalimani Metin Sabanci Bone and Joint Diseases Education and Research Hospital, Istanbul, Turkey
  • Malatya Public Health Directorate, Malatya, Turkey
Corresponding author
Dinçel, Yaşar Mahsut
ORCID
Venue
SAGE Open Medicine
Publisher
SAGE Publications
Published
2019-01
Volume
7
Pages
2050312119837480-2050312119837480
ISSN
2050-3121 (ISSN-L)
DOI
10.1177/2050312119837480
PMC
PMC6415475
OpenAlex
W2921066534
Cited by
45
References
2
Citations by year
2026: 4 · 2025: 4 · 2024: 4 · 2023: 10 · 2022: 5 · 2021: 5 · 2020: 10 · 2019: 3
FWCI
4.13
Type
journal article
Language
en
Open access
Licence
Locations
  • SAGE Open Medicine (publishedVersion, cc-by-nc)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by-nc)
  • PubMed Central (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Topics
  • Health Sciences › Medicine › Pathology and Forensic Medicine › Vitamin D Research Studies
  • Health Sciences › Medicine › Orthopedics and Sports Medicine › Sports Performance and Training
  • Health Sciences › Medicine › Physiology › Physical Activity and Health
Keywords
vitamin D, athletes, vitamin D deficiency, 25-hydroxyvitamin D, indoor sports, outdoor sports, seasonal variation, winter, sun exposure, vitamin D supplementation

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review