Introduction Many activities of daily life in modern society require sufficient time to react. These stimuli often involve choosing the best option among several possibilities. Therefore, in neuroscience, an experimental measure of a person's cognitive abilities is to subject them to a Choice Reaction Time (CRT) test. Central processing and planning of fine motor patterns occur within the cerebellum to rapidly perform choice reaction tasks (Welford, A 1980). Previous studies have shown that an individual's level of arousal (often measured as a percentage of heart rate), directly influences their cognitive performance related to processing different choices. Davranche et al. (2004) demonstrated that moderate exercise (50% of peak VO2) improves cognitive performance regarding choice reaction time. However, a more recent study found that increasing a subject's arousal only improved CRT in highly trained fencing athletes, while having no effect on the sedentary population (Mouelhi Guizani, S. et al, 2006) . Therefore, this experimental study is designed to determine the effects of heart rate variation on CRT in a young, physically active male population. Purpose The purpose of this experiment is to study the effect that heart rate has on reaction time. The information obtained will be of particular interest to athletes whose ability to react may depend on their level of arousal. It has been shown that it is possible to achieve an ideal (optimal) heart rate to minimize the individual's chosen reaction time. However, there is a lack of evidence to support this notion for the young and physically active population and it is for this reason that it is imperative to forgo this experiment. MethodologyExpe...... half of the document ..... .- Interlink force sensing resistors - Tactile swabs - Towels - self-supplied - Water bottles - self-supplied - Data collection tables - self-supplied • Manual of ACSM resources for exercise testing and prescribing guidelines. Philadelphia, Lea and Febiger, for the American College of Sports Medicine, 2006. Seventh edition.• Davranche, K. & Audiffren, M. (2004). Facilitating effects of exercise on information processing, J Sports Sci, 22, p 419-428.• Mouelhi Guizani, S., Bouzaouach, I., Tenenbaum, G., Ben Kheder, A., Feki, Y. , Bouaziz, M (2006). Simple and selected reaction times under various levels of physical load in highly trained fencers, J Sports Med Phys Fitness, 46, p 344-351. • Schmidt, R. A. (1991). Motor learning and performance: from principles to practice. Mitcham, S.A.: Human kinetics.• Welford, A.T. (1980). Reaction times. New York: Academic Press.