BACKGROUND: Reaction time (RT) is a measure of the response to a stimulus. RT plays a very important role in our lives as its practical implications may be of great consequences. Factors that can affect the average human RT include age, sex, left or right hand, central versus peripheral vision, practice, fatigue, fasting, breathing cycle, personality types, exercise, and intelligence of the subject. AIM: The aim was to compare visual RTs (VRTs) and auditory RTs (ARTs) on the basis of gender and physical activity levels of medical 1(st) year students. MATERIALS AND METHODS: The present cross-sectional study was conducted on 120 healthy medical students in age group of 18-20 years. RT for target stimulus that is, for the beep tone for measuring ART, and red circle for measuring VRT was determined using Inquisit 4.0 (Computer Software) in the laptop. The task was to press the spacebar as soon as the stimulus is presented. Five readings of each stimulus were taken, and their respective fastest RT's for each stimuli were recorded. Statistical analysis was done. RESULTS: In both the sexes' RT to the auditory stimulus was significantly less (P < 0.001) as compared to the visual stimulus. Significant difference was found between RT of male and female medical students (P < 0.001) as well as between sedentary and regularly exercising healthy medical 1(st) year students. CONCLUSION: The ART is faster than the VRT in medical students. Furthermore, male medical students have faster RTs as compared to female medical students for both auditory as well as visual stimuli. Regularly exercising medical students have faster RTs when compared with medical students with sedentary lifestyles.