1. Results. Abstract Methods Purpose Conclusions By: Christine Hernandez Faculty Sponsor: J.R. Wilson PhD. Kinesiology Research Laboratory, The University of Texas at Arlington, Arlington, TX; The Effects of Energy Drinks on Performance during a Submaximal Exercise Test The purpose of this study was to study the physiological effects that energy drinks such as Red bull have during a submaximal cycling exercise. Five UTA female students (W; age 23 + 3.08 yrs), volunteered to participate in this study. Each subject came to the Kinesiology department twice for about 60 minutes and consumed either Red Bull or Gatorade (placebo) on their testing days. Resting heart rate and blood pressures were obtained. Each subject performed a submaximal exercise test on a leg ergo meter 20 minutes after the ingestion of Red bull or Gatorade. The subjects cycled for 30 minutes, at 70% of their age predicted maximal heart rate. Every 10 minutes heart rate, blood pressure and the rate of perceived exertion (RPE) using the Borg Rating of Perceived Exertion scale were measured and recorded. The distance traveled was measured by the odometer of the cycle ergometer and recorded in kilometers. The statistical analysis demonstrated that there were significant differences between two cycle rides when Red bull and Gatorade were consumed These differences occurred at the 10, 20, and 30 minute intervals of cycling. The mean values for HR (Red bull: 130 + 13 beats·minute -1 ; Gatorade : 124 +15 beats·minute -1 ) were significantly different (p = 0.0065 ); The RPE (Red bull: 11+ 2.6; Gatorade: 12.13 + 2.9) measures also were significantly different (p value= 0.04). There was not a significant difference (p = 1.16) in the distance traveled in km at the 10 minute measurement points for either the consumption of Red bull ( 7.17 + 2.65 km) or Gatorade (6.79 + 2.69 km). Introduction: Energy Drinks are beverages that imply revitalization of the mind and body, enhancement for better performance in sports, and the stimulation of the body by boosting the energy levels. Generally, energy drinks are consumed in order to enhance the quality of performance in exercise and to boost their energy levels on performance. These beverages claim to impact exercise and enhance the body ’ s physiological responses. Purpose: The purpose of this study was to study the physiological effects that energy drinks such as Red bull have on a submaximal cycling exercise. Methods: Five UTA female students (W; age 23 + 3.08 yrs), volunteered to participate in this study. Each subject came to the Kinesiology department twice for about 60 minutes and consumed either Red Bull or Gatorade (placebo) on their testing days. Resting heart rate and blood pressures were obtained. Each subject performed a submaximal exercise test on a leg ergo meter 20 minutes after the ingestion of Red bull or Gatorade. The subjects cycled for 30 minutes, at 70% of their age predicted maximal heart rate. Every 10 minutes heart rate, blood pressure and the rate of perceived exertion (RPE) using the Borg Rating of Perceived Exertion scale were measured and recorded. The distance traveled was measured by the odometer of the ergometer and recorded in kilometers. Results: The statistical analysis demonstrated that there were significant differences between two cycle rides when Red bull and Gatorade were consumed at the 10, 20, and 30 minute intervals of cycling. The mean values for HR (Red bull: 130 + 13 beats · minute -1 ; Gatorade : 124 + 15 beats · minute -1 ) were significantly different (p = 0.0065); The RPE (Red bull: 11 + 2.6; Gatorade: 12.13 + 2.9) measures also were significantly different (p value= 0.04). There was not a significant difference (p = 1.16) in the distance traveled in km at the 10 minute measurement points for either the consumption of Red bull ( 7.17 + 2.65 km) or Gatorade (6.79 + 2.69 km). Conclusion: The results of the study indicate that Red bull energy drinks do enhance the quality of the exercise test than Gatorade providing energy to cycle for 30 minutes. The results revealed that the consumption of this energy drink had positive effects on the effort during the submaximal cycling test in females. The results of the study indicate that Red bull energy drinks do enhance the quality of the exercise test more than Gatorade and appear to provide energy to cycle for 30 minutes. The results revealed that the consumption of this energy drink had positive effects on the effort during the submaximal cycling test in females.