The Damaging Relationship Between Coffee And Exercise

KYW's Medical Reports Sponsored By Independence Blue Cross

By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) -- A cup of coffee can help give you a burst of energy, but scientists will tell you the best way to increase energy is regular sleep, and a healthy diet low in carbohydrates and sugars.

Another key point to think about when you are drinking coffee for that burst of energy is the relationship between coffee and exercise. We know that the amount of caffeine in just two cups of coffee can cut down the body's ability to increase blood-flow to the heart during exercise.

Theoretically, this means that vital blood-flow to the heart can be cut back when the body needs it most. Here's the theory: caffeine may block certain receptors in the walls of blood vessels, interfering with the normal signaling processes that cause blood vessels to dilate, or get bigger, in response to exercise.

This can work against you.