“The consumption of oral creatine monohydrate has become increasingly common among professional and amateur athletes” (Poortmans and Francaux, 2000). Creatine is a substance used by athletes and bodybuilders to increase the production of Adenosine Triphosphate (ATP), which gives them the energy they need to perform. In this experiment, creatine is added to water and its effects on Daphnia is tested. By observing the heart rate, one can determine if the creatine increases or decreases heart rate. Heart rate was chosen to be measured because one can then see how creatine affects the heart. If it is unhealthy for the Daphnia, it could potentially be unhealthy for humans. “Long-term safety of creatine supplementation has been questioned. This retrospective study was performed to examine markers related to health, the incidence of reported side effects and the perceived training benefits in athletes supplementing with creatine monohydrate” (Schilling et al. 2001).
The hypothesis is that the heart rate will increase as the concentration of the creatine increases. The anticipation is that the creatine will have little effect on the heart rate. In another study where creatine was given to athletes prior to a workout, the results showed that, “ No statistically significant differences in heart rate were observed between the treatments either during anaerobic or aerobic exercise” (Vanakoski et al. 1998). Another study, with the experiment being similar, said that creatine, “had no significant effect on peak power, work output, RPE, or peak heart rate” (Crow et al. 2006). One study was done in which athletes who were paralyzed were given creatine and then asked to perform. They then recorded the heart rate and concluded that there was no significant gain or loss due to the creatine (Perrot, 2006).
Methods
We first began the experiment by creating a 10% creatine solution. This was done by mixing 5 grams of creatine in 200 mL of water. Then, we
Cited: Crowe, M.J., A. Leicht, W. Spinks. 2006. Physiological and cognitive responses to caffeine during repeated, high-intensity exercise. International Journal of Sports Nutrition and Exercise Metabolism 5: 528-544. Perret, C., G. Mueller, H. Knecht. 2006. Influence of creatine supplementation on 800m wheelchair performance: a pilot study. Spinal Cord 5: 275-279. Poortmans, JR., M. Francaux. 2000. Adverse effects of creatine supplementation – Fact or fiction?. Sports Medicine 3: 155-170. Schilling, B.K., M. Stone, A. Utter, J. Kearney, M. Johnson, R. Coglianese, L. Smith, H. O’Bryant, A. Fry, M. Starks, R. Keith, M. Stone. Creatine supplementation and health variables: a retrospective study. Medicine and Science in Sports and Exercise 2: 183-188. Vanakoski, J., V. Kosunen, E. Meririnne, T. Seppala. 1998. Creatine and caffeine in anaerobic and aerobic exercise: effects on physical performance and pharmacokinetic considerations. International Journal of Clinical Pharmacology and Therapeutics 5: 258-262.