Vitamin D Status of Athletes with High UV-Exposure During Exercise Training1

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Peer-reviewed | Manuscript received: February 26, 2013 | Revision accepted: July 18, 2013

Vitamin D status of athletes with high UV-exposure during exercise training1

Anja Carlsohn, Friederike Scharhag-Rosenberger, Juliane Heydenreich, Frank Mayer, Potsdam

cle protein synthesis and neuromus- Summary cular control [7–9]. It has therefore been suggested that vitamin D sta- The summer vitamin D status was measured of 35 professional and recreatio- tus and physical performance may nal athletes. Professional and recreational athletes consumed 3.5 ± 5.9 g/d and be linked and this has been supported 3.9 ± 5.1 g/d vitamin D, respectively (p = 0.82). However, the serum values by some studies [1, 10, 11]. How- (90 ± 14 nmol/L and 74 ± 2 nmol/L; p = 0.03) were within the normal range. ever, recent investigations have It is possible that UV exposure during training makes a major contribution to- shown that young athletes – partic- wards meeting requirements. ularly in indoor sports – may exhibit Keywords: Vitamin D status, nutrition, sports, excercise inadequate or low serum concentrations of 25-(OH)-cholecalciferol [13, 14]. Introduction corresponding to 80–90 % of vitamin D supply [1, 2]. Objective The fat soluble vitamin D is essential A deficient vitamin D status is re- for intra- and extracellular potas- The objective of this study was to flected by the serum concentration sium and phosphate homeostasis, as record vitamin D intake and the of 25-(OH)-cholecalciferol, as 25- well as for bone mineralisation. The serum concentration of 25-(OH)- (OH)-cholecalciferol reflects vitamin recognised consequences of vitamin cholecalciferol as parameters of vita- D supply in food and from endoge- D deficiency are therefore mostly min D supply of recreational and nous synthesis [3]. For serum con- skeletal diseases, e. g. rickets or os- professional athletes and to compare centrations of 25-(OH)-cholecalci- teomalacia [1]. this with published data. ferol < 50 nmol/L, it is assumed that vitamin D supplies are inade- The current “estimate of appropriate quate [3]. In spite of the great im- Methods supply of vitamin D in the lack of portance of endogenous synthesis endogenous synthesis” (referred to During the summer months (15 for vitamin D balance and thus the below as “estimate”) of the German July to 15 September), venous blood relative independence from nutri- Nutrition Society (DGE) is 20 g/d samples were taken from 16 athletes tional supply, inadequate vitamin D for adults. However, vitamin D can in the national teams for rowing and supply is very common in the gen- also be synthesised endogenously. racing canoes (8f, 8m; 23 ± 4 years, eral population [4]. Under normal living conditions in 80.5 ± 15.3 kg; 183 ± 12 cm), as Germany, endogenous synthesis is Recording vitamin D status is not well as 19 recreational athletes (11f, indeed the most important factor, only interesting for the general pop- 8m; 25 ± 2 years, 73.3 ± 11.2 kg; ulation or for groups at risk of os- 178 ± 8 cm), in order to determine teoporosis, but also increasingly for the 25–(OH)-cholecalciferol serum healthy athletes. Aside from its func- concentration as marker of vitamin Citation: tion in bone metabolism [5] and the D supply. Before analysis, the blood Carlsohn A, Scharhag-Rosenber- resulting potential effect on fatigue samples were stored at –20 °C. The ger F, Heydenreich J, Mayer F fractures in athletes [6], vitamin D analysis was performed by im- (2013) Vitamin D status of ath- also acts through the intramuscular munochemistry, with a commercial letes with high UV-exposure dur- vitamin D receptor to influence mus- ELISA test kit (IDS Germany, Frank- ing exercise training. Ernaeh- furt/Main). rungs Umschau international 1 60(10): 174–176 The present data have already been presented During the same period in which the as a poster at the 43th Congress of Sports Med- This article is available online: icine of the German Association of Sports blood samples were taken, nutrition DOI 10.4455/eu.2013.033 Medicine in 2012 [Deutscher Sportärztekon- (including intake of food supple- gress] in Berlin. ments) was documented in a stan-

174 Ernaehrungs Umschau international | 10/2013 dardised 3-day consumption record ited serum concentrations below the Both recreational and professional and the vitamin D supply was reference range (< 50 nmol/L). athletes lay well under this figure, recorded on the basis of the German Serum concentrations < 30 nmol/L with just 4 g/d. Similarly low in- Food Database II.3 (Prodi Nutri- were not observed. takes of vitamin D have been found Science 5.7 expert, Hausach, Ger- with professional basketball players, many). A standardised 7-day activ- The correlation coefficient between with only 3.5 ± 2.0 g/d vitamin D ity protocol was used to record the mean 25-(OH)-cholecalciferol [15]. Athletes consumed similarly physical activity during the period of serum concentration and the dura- low levels of vitamin D compared to examination. tion of exercise training was calcu- the general German population [16]. lated to be r = 0.10 for the recre- The data were evaluated descrip- ational athletes, r = 0.41 for the In spite of the low consumption tively (mean ± standard deviation professional athletes and r = 0.24 of vitamin D in food, professional [SD]). In addition, the hypothesis for the two groups combined. and recreational athletes exhibited was tested that there were differences vitamin D concentrations of > 50 between professional and recre- nmol/L during the summer months ational athletes (t test for indepen- Discussion – indicating adequate endogenous dent samples, level of significance α = synthesis. Thus, the levels found in 0.05). Finally, the Pearson correla- The German Nutrition Society esti- German athletes appear to be better tion coefficient was calculated, in mates that the vitamin D require- than the levels in the rather sparse order to evaluate the correlation be- ment for adults is 20 g/d, in the data in the international literature. tween the daily duration of exercise lack of endogenous synthesis [1]. On the other hand, the latter include training and 25-(OH)-cholecalciferol serum concentrations. 30 individual value mean 95 % Results 25 confidence interval

The professional athletes trained for estimated vitamin D requirements in the lack of endogenous synthesis a mean period of 138 ± 56 min/d, 20 whereas the recreational athletes en- 15 gaged in sport or were physically ac-

tive for 72 ± 36 min/d (p = 0.004). supply (µg/d) 10 One reason for the high physical activity of the recreational athletes in 5 this group is that they frequently used the bicycle as transportation 0 means. professional athletes recreational athletes There was no significant difference Fig. 1: Supply of vitamin D to professional and recreational athletes between the two groups with respect compared with the estimated values for appropriate vitamin D to vitamin D supply, which was supply in the absence of endogenous synthesis (––––) 3.5 ± 5.9 g/d for the professional athletes, and 3.9 ± 5.1 g/d for 150 the recreational athletes (p = 0.82) individual value (v Figure 1). The serum concentra- mean 95 % 125 confidence interval tions of 25-(OH)-cholecalciferol were significantly higher for the profes- 100 sional athletes (90.1 ± 14.3 nmol/L) than for the recreational athletes 75 (73.5 ± 25.7 nmol/L, p = 0.03). (nmol/L)

Serum desired vitamin D serum concentration Nevertheless, the values in both C 50 groups were greater than 50 nmol/L, which is regarded as the lower limit 25 for the prevention of falls, fractures and premature death in older men 0 and women (v Figure 2) [4]. professional athletes recreational athletes

No professional athlete, but 21 % of Fig. 2: 25-(OH)-cholecalciferol concentration in the serum (CSerum) of pro- recreational athletes (n = 4), exhib- fessional and recreational athletes Ī

Ernaehrungs Umschau international | 10/2013 175 Science & Research | Original Contribution

data from athletes involved in indoor Conclusion based study of younger and older adults. Am sports, so that direct comparison is J Med 116: 634–639 difficult. For example, the serum During the summer months, en- 6. Tenforde AS, Sayres LC, Sainani KL, Frede- concentrations of 25-(OH)-chole- dogenous vitamin D synthesis can ricson M (2010) Evaluating the relationship calciferol in ballet dancers were 37.3 easily compensate for low nutri- of calcium and vitamin D in the prevention nmol/L in winter and 59.8 nmol/L tional intake in athletes. In future of stress fracture injuries in the young ath- in summer [14]. Serum concentra- studies, it would be interesting to lete: a review of the literature. PM R 2: 945– tions of 63.3 ± 20.8 nmol/L 25- study the supply and serum concen- 949 (OH)-cholecalciferol were observed in trations of vitamin D in athletes in 7. Beauchet O, Annweiler C, Verghese J et al. a group of 98 athletes practising the winter months and in indoor (2011) Biology of gait control: vitamin D in- various types of indoor and outdoor sports. volvement. Neurology 76: 1617–1622 sport [17]. 8. Bischoff HA, Borchers M, Gudat F et al. (2001) In situ detection of 1,25-dihydro- In the present study, it is striking xyvitamin D3 receptor in human skeletal that the recreational athletes (72 ± Jun.-Prof. Dr. rer. nat. Anja Carlsohn1, 2 muscle tissue. Histochem J 33: 19–24 2, 3, 4 36 min/d sport) exhibited signifi- Dr. phil. Friederike Scharhag-Rosenberger 9. Grimaldi AS, Parker BA, Capizzi JA et al. Dipl.-Sportwiss. Juliane Heydenreich2 (2012) 25(OH) vitamin D is associated with cantly lower vitamin D concentra- Prof. Dr. med. Frank Mayer2 tions than the professional athletes, greater muscle strength in healthy men and who were active for almost twice the 1Korrespondenzadresse: women. Med Sci Sports Exerc 45: 157–162 time (138 ± 56 min/d). As there was Pädagogische Hochschule Schwäbisch Gmünd 10. Cannell JJ, Hollis BW, Sorenson MB et al. Oberbettringer Str. 200 no difference between the two 73525 Schwäbisch Gmünd (2009) Athletic performance and vitamin D. groups with respect to vitamin D E-Mail: [email protected] Med Sci Sports Exerc 41: 1102–1110 supply, it can be assumed that the 2Hochschulambulanz der Universität Potsdam 11. Hamilton B (2011) Vitamin D and athletic Am Neuen Palais 10, 14469 Potsdam high UV exposure of professional performance: the potential role of muscle. 3Deutsche Hochschule für Prävention und athletes during exercise training Gesundheitsmanagement Saarbrücken Asian J Sports Med 2: 211–219 plays a decisive role in covering their 4Nationales Centrum für Tumorerkrankungen 12. Schmidt S, Bös K, Bergmann K et al. (2012) vitamin D requirements. On the (NCT) Heidelberg Vitamin-D-Versorgung und körperliche Leis- Medizinische Onkologie other hand, in both groups (recre- tungsfähigkeit. Ernährungs Umschau 60: ational and professional athletes) and Conflict of Interest 564–571 in the overall sample, there was only The authors declare no conflict of interest ac- 13. Ducher G, Kukuljan S, Hill B et al. (2011) a slight or moderate combination be- cording to the guidelines of the International Vitamin D status and musculoskeletal tween the daily duration of exercise Committee of Medical Journal Editors. health in adolescent male ballet dancers a training and 25-(OH)-cholecalci- pilot study. J Dance Med Sci 15: 99–107 ferol serum concentration. In gen- 14. Wolman R, Wyon MA, Koutedakis Y (2013) eral, it can be concluded that vitamin Vitamin D status in professional ballet D supply in the summer months is References dancers: Winter vs. summer. J Sci Med Sport adequate for athletes who frequently [Feb 1, 2013; Epub ahead of print] train outside. 1. Heseker H, Stahl A, Strohm D (2012) Vita- 15. Bescos Garcia R, Rodriguez Guisado FA min D. Physiologie, Funktionen, Vorkommen, (2011) Low levels of vitamin D in profes- Referenzwerte und Versorgung in Deutsch- sional basketball players after wintertime: land. Ernährungs Umschau 59: 232–239 relationship with dietary intake of vitamin Study limitations 2. Holick MF (2007) Vitamin D deficiency. N D and calcium. Nutr Hosp 26: 945–951 The study limitations include the Engl J Med 357: 266–281 16. Max Rubner-Institut (2008) Nationale low number of volunteers and the 3. Holick MF, Binkley NC, Bischoff-Ferrari HA Verzehrsstudie II, Ergebnisbericht Teil 2. lack of information about vitamin D et al. (2011) Evaluation, treatment, and URL: www.bmelv.de/SharedDocs/Down supply and 25-(OH)-cholecalciferol prevention of vitamin D deficiency: an En- loads/Ernaehrung/NVS_Ergebnisbericht serum concentrations of the same docrine Society clinical practice guideline. J Teil2.pdf?__blob=publicationFile Zugriff volunteers in winter or spring. In Clin Endocrinol Metab 96: 1911–1930 12.01.13 addition, the recreational athletes 4. Linseisen J, Bechthold A, Bischoff-Ferrari HA 17. Constantini NW, Arieli R, Chodick G, Dub- practised different types of sport et al. Vitamin D und Prävention aus- nov-Raz G (2010) High prevalence of vita- (mainly fitness training, football and gewählter chronischer Erkrankungen – Stel- min D insufficiency in athletes and dancers. jogging), so that it is unclear how lungnahme. Deutsche Gesellschaft für Clin J Sport Med 20: 368–371 much time was spent outdoors dur- Ernährung e. V. (Hg), Bonn (2011) ing exercise training. Thus, UV ex- 5. Bischoff-Ferrari HA, Dietrich T, Orav EJ, posure during exercise training and Dawson-Hughes B (2004) Positive associa- other leisure activities remains un- tion between 25-hydroxy vitamin D levels DOI: 10.4455/eu.2013.033 known. and bone mineral density: a population-

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