The study measured drinks on just one occasion, and researchers say the effect of daily wine or alcohol intake may be different.
The study is in this month's edition of the American Journal of Physiology, Heart and Circulatory Physiology.
Study: One glass of wine good for heart
Doctors at Toronto General Hospital have found that one glass of red wine or alcohol relaxed the blood vessels, which reduced the amount of work the heart had to do. But after two drinks, the heart rate increased.
