Markers of Bone Health, Renal Function, Liver Function, Anthropometry and Perception of Mood: A Comparison between Flat and National Hunt Jockeys

Abstract

Given the requirement of professional jockeys to make-weight daily, we tested the hypothesis that Flat and National Hunt (Jump) jockeys would display compromised health markers (bone health, vitamin D, liver and kidney function and mood) compared with established clinical norms, with Flat jockeys affected the greater. Daily energy intake was lower in Flat compared with Jump jockeys (6.11±1.25 vs. 7.47±0.83 MJ.day^− 1, P=0.01) whereas there was no difference in urine osmolality (811±198 vs. 678±317 mOsmol.kg^− 1 respectively, P=0.13). Serum total 25(OH)D was insufficient in Flat and Jump jockeys (37.6±28 vs. 35.1±14 nmol.L^− 1) respectively although there was no difference between groups (P=0.79). Markers of bone metabolism (Plasma β-carboxy-terminal cross-linked teleopeptide (CTX) and Intact Parathyroid Hormone (PTH) and liver and kidney function were within clinical normative ranges although CTX and PTH were higher than average. Abnormal mood profiles were observed in both groups although significantly poorer in the Flat jockeys (P=0.01). We conclude that the current practices of jockeys to make-weight may have detrimental effects upon their health with Flat jockeys affected more so than Jump jockeys. Future studies should investigate the effects of improved dietary practices on the mental and physical health of Flat and Jump jockeys.

Key words

jockey - weight-making - horse-racing - mood - health

• References

• 1 Aintree Broadcasting of the Grand National 2012: Available from http://www.aintree.co.uk/pages/broadcasting-of-the-grand-national/
• 2 Alderman BL, Landers DM, Carlson J, Scott JR. Factors related to rapid weight loss practices among international-style wrestlers. Med Sci Sports Exerc 2004; 36: 249-252
• 3 Banfi G, Lombardi G, Colombini A, Lippi G. Bone metabolism markers in sports medicine. Sports Med 2010; 40: 697-714
• 4 Bingham S. The dietary assessment of individuals; methods, accuracy, new techniques and recommendations. Nutr Abstr Rev Ser Hum Exp 1987; 57: 705-742
• 5 Burke L. Practical issues in nutrition for athletes. J Sports Sci 1995; 13: S83-S90
• 6 Caulfield MJ, Karageorghis CI. Psychological effects of rapid weight loss and attitudes towards eating among professional jockeys. J Sports Sci 2008; 26: 877-883
• 7 Centers-for-Disease-Control-and-Prevention . Hyperthermia and dehydration-related deaths associated with intentional rapid weight loss in three collegiate wrestlers–North Carolina, Wisconsin, and Michigan, November-December 1997. JAMA 1998; 279: 824-825
• 8 Cotugna N, Snider OS, Windish J. Nutrition assessment of horse-racing athletes. J Community Health 2011; 36: 261-264
• 9 Dolan E, O’Connor H, McGoldrick A, O’Loughlin G, Lyons D, Warrington G. Nutritional, lifestyle, and weight control practices of professional jockeys. J Sports Sci 2011; 29: 791-799
• 10 Dolan E, McGoldrick A, Davenport C, Kelleher G, Byrne B, Tormey W, Smith D, Warrington GD. An altered hormonal profile and elevated rate of bone loss are associated with low bone mass in professional horse-racing jockeys. J Bone Miner Metab 2012; epub ahead of print
• 11 Ebert TR, Martin DT, Bullock N, Mujika I, Quod MJ, Farthing LA, Burke LM, Withers RT. Influence of hydration status on thermoregulation and cycling hill climbing. Med Sci Sports Exerc 2007; 39: 323-329
• 12 Filaire E, Maso F, Degoutte F, Jouanel P, Lac G. Food restriction, performance, psychological state and lipid values in judo athletes. Int J Sports Med 2001; 22: 454-459
• 13 Fraser WD. Standardization of vitamin D assays: art or science?. Ann Clin Biochem 2009; 46: 3-4
• 14 Glendenning P, Noble JM, Taranto M, Musk AA, McGuiness M, Goldswain PR, Fraser WD, Vasikaran SD. Issues of methodology, standardization and metabolite recognition for 25-hydroxyvitamin D when comparing the DiaSorin radioimmunoassay and the Nichols Advantage automated chemiluminescence protein-binding assay in hip fracture cases. Ann Clin Biochem 2003; 40: 546-551
• 15 Glendenning P, Taranto M, Noble JM, Musk AA, Hammond C, Goldswain PR, Fraser WD, Vasikaran SD. Current assays overestimate 25-hydroxyvitamin D3 and underestimate 25-hydroxyvitamin D2 compared with HPLC: need for assay-specific decision limits and metabolite-specific assays. Ann Clin Biochem 2006; 43: 23-30
• 16 Hamilton B. Vitamin D and human skeletal muscle. Scand J Med Sci Sports 2010; 20: 182-190
• 17 Harriss DJ, Atkinson G. Update-ethical standards in sport and exercise science research. Int J Sports Med 2011; 32: 819-821
• 18 Kanis JA, Borgstrom F, De Laet C, Johansson H, Johnell O, Jonsson B, Oden A, Zethraeus N, Pfleger B, Khaltaev N. Assessment of fracture risk. Osteoporos Int 2005; 16: 581-589
• 19 Labadarios D, Kotze J, Momberg D, Kotze TJ. Jockeys and their practices in South Africa. World Rev Nutr Diet 1993; 71: 97-114
• 20 Leydon MA, Wall C. New Zealand jockeys’ dietary habits and their potential impact on health. Int J Sport Nutr Exerc Metab 2002; 12: 220-237
• 21 Maughan RJ, Shirreffs SM. Dehydration and rehydration in competitive sport. Scand J Med Sci Sports 2010; 20 (Suppl. 03) 40-47
• 22 Maxwell JD. Seasonal variation in vitamin D. Proc Nutr Soc 1994; 53: 533-543
• 23 McKenna MJ, Freaney R, Byrne P, McBrinn Y, Murray B, Kelly M, Donne B, O’Brien M. Safety and efficacy of increasing wintertime vitamin D and calcium intake by milk fortification. QJM 1995; 88: 895-898
• 24 Moore JM, Timperio AF, Crawford DA, Burns CM, Cameron-Smith D. Weight management and weight loss strategies of professional jockeys. Int J Sport Nutr Exerc Metab 2002; 12: 1-13
• 25 Morton JP, Robertson C, Sutton L, MacLaren DP. Making the weight: a case study from professional boxing. Int J Sport Nutr Exerc Metab 2010; 20: 80-85
• 26 Racing-Post Racing Post Statistics2011: Available from http://www.racingpost.com/horses/seasonal_stats_home.sd
• 27 Raglin JS, Morgan WP, O’Connor PJ. Changes in mood states during training in female and male college swimmers. Int J Sports Med 1991; 12: 585-589
• 28 Rodriguez NR, DiMarco NM, Langley S. Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance. J Am Diet Assoc 2009; 109: 509-527
• 29 Ross A, Taylor C, Yaktine A, Del Valle H. Dietary Reference Intakes for Calcium and Vitamin D. Washington DC: The National Academic Press; 2011
• 30 Schwarz JM, Neese RA, Turner S, Dare D, Hellerstein MK. Short-term alterations in carbohydrate energy intake in humans. Striking effects on hepatic glucose production, de novo lipogenesis, lipolysis, and whole-body fuel selection. J Clin Invest 1995; 96: 2735-2743
• 31 Shirreffs SM, Maughan RJ. Urine osmolality and conductivity as indices of hydration status in athletes in the heat. Med Sci Sports Exerc 1998; 30: 1598-1602
• 32 Sutton L, Scott M, Wallace J, Reilly T. Body composition of English Premier League soccer players: influence of playing position, international status, and ethnicity. J Sports Sci 2009; 27: 1019-1026
• 33 Terry PC, Lane AM, Lane HJ, Keohane L. Development and validation of a mood measure for adolescents. J Sports Sci 1999; 17: 861-872
• 34 Waldron-Lynch F, Murray BF, Brady JJ, McKenna MJ, McGoldrick A, Warrington G, O’Loughlin G, Barragry JM. High bone turnover in Irish professional jockeys. Osteoporos Int 2010; 21: 521-525
• 35 Warrington G, Dolan E, McGoldrick A, McEvoy J, Macmanus C, Griffin M, Lyons D. Chronic weight control impacts on physiological function and bone health in elite jockeys. J Sports Sci 2009; 27: 543-550
• 36 Willis KS, Peterson NJ, Larson-Meyer DE. Should we be concerned about the vitamin D status of athletes?. Int J Sport Nutr Exerc Metab 2008; 18: 204-224
• 37 Wilson G, Chester N, Eubank M, Crighton B, Drust B, Morton J, Close G. An alternate dietary strategy to make weight improves mood, decreases body fat and removes the necessity for dehydration: A case-study from a professional jockey. Int J Sport Nutr Exerc Metab 2012; 22: 225-231