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Cited by 246Vitamin D Research StudiesSports Performance and TrainingExercise and Physiological Responses

Assessment of vitamin D concentration in non-supplemented professional athletes and healthy adults during the winter months in the UK: implications for skeletal muscle function

Close, G.L., Russell, J., Cobley, J.N., Owens, D.J., Wilson, G., Gregson, W., Fraser, W.D., Morton, J.P.·2013·Journal of Sports Sciences
DOI 10.1080/02640414.2012.733822
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Abstract

The current study implemented a two-part design to (1) assess the vitamin D concentration of a large cohort of non-vitamin D supplemented UK-based athletes and 30 age-matched healthy non-athletes and (2) to examine the effects of 5000 IU · day(-1) vitamin D(3) supplementation for 8-weeks on musculoskeletal performance in a placebo controlled trial. Vitamin D concentration was determined as severely deficient if serum 25(OH)D < 12.5 nmol · l(-1), deficient 12.5-30 nmol · l(-1) and inadequate 30-50 nmol · l(-1). We demonstrate that 62% of the athletes (38/61) and 73% of the controls (22/30) exhibited serum total 25(OH)D < 50 nmol · l(-1). Additionally, vitamin D supplementation increased serum total 25(OH)D from baseline (mean ± SD = 29 ± 25 to 103 ± 25 nmol · l(-1), P = 0.0028), whereas the placebo showed no significant change (53 ± 29 to 74 ± 24 nmol · l(-1), P = 0.12). There was a significant increase in 10 m sprint times (P = 0.008) and vertical-jump (P = 0.008) in the vitamin D group whereas the placebo showed no change (P = 0.587 and P = 0.204 respectively). The current data supports previous findings that athletes living at Northerly latitudes (UK = 53° N) exhibit inadequate vitamin D concentrations (<50 nmol · l(-1)). Additionally the data suggests that inadequate vitamin D concentration is detrimental to musculoskeletal performance in athletes. Future studies using larger athletic groups are now warranted.

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Crossref · 10.1080/02640414.2012.733822

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  • Supplementation with high doses of 5000-10,000 IU/day of vitamin D3 is effective in treating athletes with 25(OH)D deficiency.

    “It is widely known that supplementation with high doses of 5000–10,000 IU/day of vitamin D3 is effective in treating athletes with 25(OH)D deficiency [9,14,42].”

    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 [14]

  • 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 [14]

  • Vitamin D supplementation in a high dose of 5000 IU per day for 8 weeks improved vertical jump height, 10 m sprint times and VO2max in competitive soccer players.

    “In the studies of Jastrzebska [7] and Close [14], vitamin D supplementation in a high dose of 5000 IU per day for 8 weeks improved vertical jump height, 10 m sprint times and VO2max in competitive soccer players [7,14].”

    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 [14]

  • In our laboratory, detrimental effects on muscle function have been reported when vitamin D concentrations are below 30 nmol/L, with no performance-enhancing effects of vitamin D supplements if the starting concentration is around 50 nmol/L.

    “In our laboratory, we have reported detrimental effects on muscle function when concentrations are below 30nmol/L [140] with no performance enhancing effects of vitamin D supplements if the starting concentration is around 50nmol/L [145].”

    From New strategies in sport nutrition to increase exercise performance (2016) · cites this paper as [140]

  • Many athletes are vitamin D deficient, largely due to a sun-shy lifestyle and poor dietary sources, even those living in sunny climates.

    “This emerging knowledge, combined with a plethora of research suggesting that many athletes are vitamin D deficient [140], largely due to a sun-shy lifestyle and poor dietary sources of vitamin D, even those living in sunny climates [141] has resulted in vitamin D being one of the most widely supplemented vitamins in sports nutrition.”

    From New strategies in sport nutrition to increase exercise performance (2016) · cites this paper as [140]

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Authors
Close, G. L., Russell, J., Cobley, J. N., Owens, D. J., Wilson, G., Gregson, W., Fraser, W. D., & Morton, J. P.
Affiliations
  • Liverpool John Moores University (GB)
  • University of East Anglia (GB)
Corresponding author
Close, G.L.
ORCID
Venue
Journal of Sports Sciences
Publisher
Informa UK Limited
Published
2013-02
Volume
31
Issue
4
Pages
344-353
ISSN
  • 0264-0414 (ISSN-L)
  • 1466-447X
DOI
10.1080/02640414.2012.733822
OpenAlex
W2019663454
Cited by
246
References
44
Citations by year
2026: 8 · 2025: 10 · 2024: 11 · 2023: 16 · 2022: 15 · 2021: 15 · 2020: 29 · 2019: 29 · 2018: 22 · 2017: 16 · 2016: 20 · 2015: 15 · 2014: 27 · 2013: 13
FWCI
12.55
Type
journal article
Language
en
Open access
closed
Locations
  • Journal of Sports Sciences (publishedVersion)
  • PubMed (publishedVersion)
  • Discovery Research Portal (University of Dundee) (submittedVersion)
  • UEA Digital Repository (University of East Anglia) (submittedVersion)
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 › Rehabilitation › Exercise and Physiological Responses
Keywords
vitamin D status, vitamin D deficiency, vitamin D supplementation, vitamin D3, professional athletes, sprint performance, vertical jump, 25-hydroxyvitamin D, winter, latitude, United Kingdom
MeSH terms
Adolescent, Adult, Physical Exertion, United Kingdom, Humans, Male, Movement, Running, Seasons, Sports, Vitamin D, Vitamin D Deficiency, Prevalence, Case-Control Studies, Muscle, Skeletal, Dietary Supplements, Athletic Performance, Young Adult

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