Impact of caffeine consumption on heart rate and blood pressure during rest and exercise

Abstract

Introduction: Several studies have evaluated the impact of caffeine consumption on athletic performance from different aspects. But, the findings are varied. The aim of this research was evaluating the impact of caffeine consumption on some of the cardiovascular factors including heart rate and blood pressure during rest, end of exercise, and during the 3rd and 5th minutes of recovery. Material and Method: The subjects of this study included 20 female athletes, participating in the study as volunteers. Two exercise tests were performed separately during one week. The subjects used placebo in the 1st and caffeine (5mg/kg) in the second test sessions. Heart rate and blood pressure were measured during rest, at the end of the exercise testing and during the 3rd and 5th minutes of recovery after submaximal test. Maximal oxygen consumption (VO2max) was measured using Fax submaximal cardiorespiratory test. Paired t- test was used for analysis of data. Results: Caffeine consumption was not significantly effective on Vo2max, heart rate during rest and at the end of exercise, and blood pressure recorded at the end of the exercise. Caffeine consumption caused a significant increase in the heart rate during 3rd and 5th minutes of recovery, and in blood pressure during rest, 3rd and 5th minutes of recovery in athletes. Conclusion: Due to the increase in blood pressure and heart rate as a result of caffeine, caffeine consumption (5 mg/kg) before submaximal exercise is not recommended, especially in those who suffer hypertension or cardiac disease or do exercise for health or athletic purposes.