Acute effects of carbohydrate gel and isotonic usage on power, heart rate and glucose levels in elite cyclists

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Gürhan Suna
İbrahim Kubilay Türkay


Cyclist, Carbohydrate Gel, Isotonic Drink


Study Objective: This study aimed to compare the acute effects of carbohydrate gel and isotonic usage on power, heart rate (HR), and glucose levels of elite cyclists. Method: Twenty licensed cyclists participated in the study voluntarily. Cyclists are randomly divided into two groups (The first group: carbohydrate gel receiving group; second group: isotonic drink receiving group). Cyclists performed about one hour of velodrome training. The first group continued to operate using one energy carbohydrate gel in the fifth minute of the training. The second group used a 2 scale (27 g) electrolyte and carbohydrate mixture in 500 ml water and added powder product during the training. Athletes' mean HR values were recorded with the Garmin brand watch. The mean power (watt) values of the athletes were also obtained with the Garmin Power meter. Heart rate and power values were compared as the mean values after the training that the athletes applied after carbohydrate gel and isotonic drink intake. OKmeter Optima OK-10H (Taiwan) sugar meter was used in the measurement of blood glucose values of cyclists. Glucose measurement was taken pre- and post-test. The analysis of data was made in the statistical package program by using “Descriptive statistics”, “Independent samples-t Test” and “Repeated Measures Analysis of Variance (ANOVA)” for comparison. Results: There were no significant differences in the mean HR, mean power, and glucose pre-and post-test values of the cyclists who took carbohydrate gel and isotonic drink before and after the training (p >0.05). Conclusion: As a result, carbohydrate gel or isotonic usage during cyclists’ sports activity didn’t effect on performance and physiological properties.


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1. Özen G. Elit bisikletçilerin fiziksel, fizyolojik özelliklerinin ve izokinetik kuvvet düzeylerinin performans parametrelerine etkisinin incelenmesi. Ankara Üniversitesi, Sağlık Bilimleri Enstitüsü, Doktora Tezi, Ankara. 2018. (in Turkish)
2. Meyer NL, Manore MM, Beming J. Food and fluid recommendations for before, during and after exercise. American College of Sports Medicine 2012;16(3):7-12.
3. Gollnick PD. Energy metabolism and prolonged exercise. InLamb, D.R. &Murray, R. (Eds) Perspectives in Exercise Science and Sports Medicine. Prolonged Exercise. Indianapolis: Benchmark Press. 2001;1-37.
4. Hargreaves M. Metabolic responses to carbohydrate ingestion: Effects on exercise performance. In D. R. Lamb & R. Murray (Eds.), Perspectives in exercise science and sports medicine. Carmel, IN: Cooper 1999;93-124.
5. Luden ND, Saunders MJ, D’Lugos AC, et al. Carbohydrate mouth rinsing enhances high intensity time trial performance following prolonged cycling. Nutrients 2016;8(9):576.
6. Jeukendrup AE. Carbohydrate and exercise performance: the role of multiple transportable carbohydrates. Current Opinion in Clinical Nutrition & Metabolic Care 2010;13(4):452-457.
7. Katch VL, McArdle WD, Katch FI. Factors affecting physiologic function. E. Lupash (Ed.), Essentials of exercise physiology. China: Lippincott Williams and Wilkins. 2011;4:502-505.
8. Wirnitzer KC, Kornexl E. Exercise intensity during an 8-day mountain bike marathon race. Eur J Appl Physiol 2008;104: 999–1005.
9. Patlar S. Effect of game form on endurance and respiration parameters with continuous running in football players (Doctoral Thesis). Selcuk University Institute of Health Sciences. 1999. (in Turkish)
10. Suna G, Alp M. Comparison of strength, heart rate, oxygen saturation and technical test values of 12–14 year male tennis players in competition period. Journal of Education and Learning 2019;8(6):187-194.
11. Pündük Z, Öztürk S. Evaluation of overloading with physical performance parameters in elite cyclists and triathletes during the training season. Journal of Sports and Performance Research 2019;10 (2):104-113
12. Müniroğlu S, Koz M, Atıl M, et al. Examination of the physical and physiological characteristics of a football team fighting in Turkish 1st professional league. Gazi Physical Education and Sports Sciences Congress Proceedings 2000:109-115. (in Turkish)
13. Alp M, Görür B. Comparison of explosive strength and anaerobic power performance of taekwondo and karate athletes. Journal of Education and Learning, 2020;9(1):149-155.
14. Earnest CP, Lancaster SL, Rasmussen CJ, et al. Low vs. high glycemic index carbohydrate gel ingestion during simulated 64-km cycling time trial performance. The Journal of Strength & Conditioning Research 2004;18(3):466-472.
15. Khoo EYH, Wallis J, Tsintzas K, et al. Effect of exenatide on circulating glucose, insülin, glikagon, cortisol and catecholamines in healthy volunteers. Diabetologia 2010;53:139-43.
16. Aydın C, Gökdemir K, Cicioğlu G. Aerobik egzersiz sonrasında insülin ve kan glikoz değerlerinin incelenmesi. Spor Bilimleri Dergisi, Hacettepe J. of Sport Sciences 2000; 11 (1-2-3-4), 47-55. (in Turkish)
17. Moghadasi M, Nuri R, Ahmadi N. Effects of 8 weeks high intensity aerobic exercise on serum retinol binding protein 4, cortizol and insulin levels in female athletes. Brazilian Journal of Biomotricity 2013;7(1):37-42.
18. Brooks D, Bradley JL, Lane P, et al. Assessment of the effects of an isotonic carbohydrate gel on exercise performance. Medicine & Science in Sports & Exercise 2002;34(5):139.
19. Campbell C, Prince D, Braun M, et al. Carbohydrate-supplement form and exercise performance. International journal of sport nutrition and exercise metabolism 2008; 18(2):179-190.
20. Casa DJ, Armstrong LE, Hillman SK, et al. National Athletic Trainers' Association position statement: fluid replacement for athletes. Journal of athletic training, 2000;35(2):212.
21. Harper LD, Briggs MA, McNamee G, et al. Physiological and performance effects of carbohydrate gels consumed prior to the extra-time period of prolonged simulated soccer match-play. J Sci Med Sport. 2016; 19(6):509-514.
22. Demiriz M, Erdemir İ, Kayhan RF. Farklı dinlenme aralıklarında yapılan anaerobik interval antrenmanın, aerobik kapasite, anaerobik eşik ve kan parametreleri üzerine etkileri. Uluslararası Spor Egzersiz ve Antrenman Bilimi Dergisi 2015;1(1):1-8. (in Turkish)
23. Phillips SM, Turner AP, Sanderson MF, et al. Carbohydrate gel ingestion significantly improves the intermittent endurance capacity, but not sprint performance, of adolescent team games players during a simulated team games protocol. Eur J Appl Physiol. 2012; 112(3):1133-1141.
24. Beyleroğlu M. The effect of carbohydrate gel consumption on elite mountain bikers’ time to exhaustion and blood glucose metabolism. Progress in Nutrition 2019;21(1):19-24.
25. Patterson SD, Gray SC. Carbohydrate-gel supplementation and endurance performance during intermittent high intensity shuttle running. Int J Sport Nutr Exerc Metab. 2007; 17(5):445-455.