Table 3. Summary table with practical guidelines for the proposed use of dietary supplements by long-track speed skaters Event(s) Dietary supplement Creatine monohydrate Suggested daily dose Acute effect: 20 g; chronic effect: 20 g first 6 d thereafter 2 g*d^-162 Supplementation instructions With a dose of 20 g*d^-1 – 4 × 5 g; dissolved in hot water + CHO drink or snack29 Supplementation period Acute effect: 5-7 d;27 chronic effect: strength training period Acute effect: 500, 1000, and 1500 m; chronic effect: all events for which strength and sprint training is used β-alanine 4-6.4 g18 Divided over 0.8 g servings19 Sodium bicarbonate 0.3-0.5 g·kg-1 *d^-120 BM 2-2.5 h prior to exercise; spread the dose over 30-60 min + fluid and carbohydrate rich meal46 Dietary nitrate 2 to 4 × 70 mL concentrated NO3 -)58 - rich beetroot (8.4 to 16.8 moll NO3 CHO, carbohydrates; BM, body mass. Divide the dose in 2; morning and evening59 At least 4 wk and no longer than 10 wk18 Acute protocol, 1 d; chronic protocol, 6 d47 All events, except the 500 m38 All long-track events, with a smaller effect for longer events20 15 d59 All, especially when performed in hypoxia Possible side effects Acute effect: an average 1.2 ± 0.3% increase in BM due to water retention24 Washout period After 5-7 d of 20g*d^-1 about 4 weeks63 Mild paraesthesia (irritation of the skin, prickly sensation)19,37,39,40 Gastrointestinal discomfort; 1-2% increase in BM15 6-15 weeks after 5-6 weeks 4.8 g*d^-1 β-alanine supplementation64 24 h for acute protocol; at least within 10 d for the chronic protocol47 Beeturia (red urine) and red stools, harmless. No harmful side effects reported.54 Unknown, at least within 10 d59 moxic and hypoxic environments. Athletes wanting to explore the possible ergogenic effects of these supplements should test the efficacy, under supervision of qualified personal, in training situations or minor competitions. References 1. De Koning JJ. World records: how much athlete? How much technology? Int J Sports Physiol Perform 2010;5(2):262-267. 2. Van Ingen Schenau GJ, Cavanagh PR. Power equations in endurance sports. J Biomech 1990;23(9):865-881. 3. De Koning JJ, Foster C, Lampen J, Hettinga F, Bobbert MF. Experimental evaluation of the power balance model of speed skating. J Appl Physiol 2005;98(1):227-233. 4. Joyner MJ, Coyle EF. Endurance exercise performance: the physiology of champions. J Physiol 2008;586(1):35-44. 5. List of speed skating records. Wikipedia 2014. Available at: http:// en.wikipedia.org/wiki/List_of_speed_skating_records. Accessed October 8, 2014. 6. Noordhof DA, Foster C, Hoozemans M JM, de Koning JJ. The association between changes in speed skating technique and changes in skating velocity. Int J Sports Physiol Perform 2014;(9(1)):68-76. 7. Foster C, Rundell KW, Snyder AC, Stray-Gundersen J, Kemkers G, Thometz N, Broker J, Knapp E. Evidence for restricted muscle blood flow during speed skating. Med Sci Sports Exerc 1999;31(10):1433-1440. 8. Rundell KW, Kenneth W. Compromised oxygen uptake in speed skaters during treadmill in-line skating. Med Sci Sports Exerc 1996;28(1):120127. 9. Foster C, de Koning JJ. Physiological perspectives in speed skating. In: Handbook of Competitive Speed Skating. Leeuwarden, the Netherlands: Eisma Publishers bv; 1999:117-137. 10. Snyder AC, Schulz LO, Foster C. Voluntary consumption of a carbohydrate supplement by elite speed skaters. J Am Diet Assoc 1989;89(8):1125-1127. 11. Parolin ML, Chesley A, Matsos MP, Spriet LL, Jones NL, Heigenhauser GJ. Regulation of skeletal muscle glycogen phosphorylase and PDH during maximal intermittent exercise. Am J Physiol 1999;277(5 Pt nummer 3 | november 2015 | Sport & Geneeskunde 15 Pagina 14
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