The DOI matches its Crossref record; 44 of the 44 references it cites were found in a registry or an index.
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
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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In the citing paper
“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]
In the citing paper
“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]
In the citing paper
“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 the citing paper
“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]
In the citing paper
“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]
Citations
Cites
Norman, A. W. (1979) · Cited by 3,769
Holick, M. F. (2004) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/80.6.1678s · Cited by 2,799
Vitamin D deficiency: a worldwide problem with health consequences
Holick, M. F., & Chen, T. C. (2008) · The American Journal of Clinical Nutrition · doi:10.1093/ajcn/87.4.1080s · Cited by 2,689
Dusso, A., Brown, A. J., & Slatopolsky, E. (2005) · American Journal of Physiology-Renal Physiology · doi:10.1152/ajprenal.00336.2004 · Cited by 1,177
Hathcock, J. N., Shao, A. E., Vieth, R., & Heaney, R. P. (2007) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/85.1.6 · Cited by 883
Vitamin D in preventive medicine: are we ignoring the evidence?
Zittermann, A. (2003) · British Journal Of Nutrition · doi:10.1079/bjn2003837 · Cited by 872
McCollum Award Lecture, 1994: Vitamin D—new horizons for the 21st century
Holick, M. F. (1994) · American Journal of Clinical Nutrition · doi:10.1093/ajcn/60.4.619 · Cited by 634
Vitamin D Receptor Expression in Human Muscle Tissue Decreases with Age
Bischoff-Ferrari, H., Borchers, M., Gudat, F., Dürmüller, U., Stähelin, H., & Dick, W. (2004) · Journal of Bone and Mineral Research · doi:10.1359/jbmr.2004.19.2.265 · Cited by 585
Hypovitaminosis D Myopathy Without Biochemical Signs of Osteomalacic Bone Involvement
Glerup, H., Mikkelsen, K., Poulsen, L., Hass, E. E., Overbeck, S., Andersen, H., Charles, P., & Eriksen, E. F. (2000) · Calcified Tissue International · doi:10.1007/s002230010085 · Cited by 514
Dawson‐Hughes, B., Dallal, G. E., Krall, E. A., Harris, S. S., Sokoll, L. J., & Falconer, G. (1991) · Annals of Internal Medicine · doi:10.7326/0003-4819-115-7-505 · Cited by 499
Research works printed but not linked: 6
- Baechle T., 2008, Essentials of Strength Training and Conditioning3rd ed.
- Bescos Garcia R., 2011, Nutricion Hospitalaria, 26, 945
- Cannell J.J., 2008, Alternative Medicine Reviews, 13, 6
- Getchell B., 1979, Physical fitness: A way of life2nd ed.
- Hamilton B., 2010, Scandinavian Journal of Medicine & Science in Sports, 20, 182
- Soliman A., 2008, Pediatric Endocrinology Reviews, 6, 155
Cited by
Sorted by citations
IOC Consensus Statement: Dietary Supplements and the High-performance Athlete
Maughan, R. J., Burke, L. M., Dvorak, J., Larson-Meyer, D. E., Peeling, P., Phillips, S. M., Rawson, E. S., Walsh, N. P., Garthe, I., Geyer, H., et al. (2018) · British Journal of Sports Medicine · doi:10.1136/bjsports-2018-099027 · Cited by 1,004
Beaudart, C., Buckinx, F., Rabenda, V., Gillain, S., Cavalier, E., Slomian, J., Petermans, J., Reginster, J.-Y., & Bruyère, O. (2014) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jc.2014-1742 · Cited by 676
IOC Consensus Statement: Dietary Supplements and the High-Performance Athlete
Maughan, R. J., Burke, L. M., Dvorak, J., Larson-Meyer, D. E., Peeling, P., Phillips, S. M., Rawson, E. S., Walsh, N. P., Garthe, I., Geyer, H., et al. (2018) · International Journal of Sport Nutrition and Exercise Metabolism · doi:10.1123/ijsnem.2018-0020 · Cited by 540
Dietary reference values for vitamin D
EFSA Panel on Dietetic Products, N. A. A. (. (2016) · EFSA Journal · doi:10.2903/j.efsa.2016.4547 · Cited by 366
Exercise‐induced muscle damage: What is it, what causes it and what are the nutritional solutions?
Owens, D. J., Twist, C., Cobley, J. N., Howatson, G., & Close, G. L. (2018) · European Journal of Sport Science · doi:10.1080/17461391.2018.1505957 · Cited by 309
Metadata
- 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.
- 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
- 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 › Endocrinology, Diabetes and Metabolism › Vitamin D Research Studies
- Health Sciences › Medicine › Orthopedics and Sports Medicine › Sports Performance and Training
- Health Sciences › Medicine › Physiology (medical) › 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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