|MadSci Network: Anatomy|
Hi Mark, Let me see if I can provide some insight into the question you have asked. The increase you see in your pulse rate you see upon taking a gulp of coffee may be a psychological response. If you beleive that the caffeine in coffee is supposed to increase your heart rate, you may have pre-conditioned yourself to this response. It would take longer that than you have indicated for the caffeine to enter your blood stream, and if you drink coffee regularly one gulp may not be enough to cuase the response you see. If you were to drink warm water without coffee or decaffeinatred coffee, would you see the same response? For a controlled experiment, you should use a number of subjects and perhaps use decaffeinated coffee and coffee with caffeine. Even under these conditions the stress of having their pulse rate monitored may cause an increase in their heart rate. I hope this provides some insight into what yuo obsereved. Al Bushway Professor of Food Science
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