Effect of Caffeine on Heart Function

An Evaluation of the Heart Rate, Blood Pressure and Repolarization Effects of an Energy Drink as Compared to Coffee

• The primary objective of this study is to assess the effect of an energy drink on ventricular repolarization as measured by the interval between the cardiac Q wave and the cardiac T wave (QT interval)obtained from the body surface ECG.
• The secondary objective is to assess the effects of an energy drink on heart rate and blood pressure (hemodynamic effects).

To place the observed changes in context, comparison will be made to a commonly consumed drink, coffee: Starbuck's K-cup Breakfast Blend.

This study will assess cardiac repolarization before and after three conditions each of which will involve the subject drinking beverages of varying caffeine content.

Inclusion Criteria:

• Healthy
• BMI between 24 - 29

Exclusion Criteria:

• Resting heart rate below 60 bpm
• Resting heart rate above 88 bpm
• Cardiovascular or metabolic disease