Team, I, too, experience "shortness of breath" upon starting mild exertion. I blame it on my taking Toprol XL beta blocker to lower my marginal blood pressure. I have always had a lower-than-normal pulse rate and now with the Toprol my resting pulse rate is often as low as 44 per minute. I believe that it just takes a minute or so to "rev up" my heart rate. After that initial problem, it goes away. Milton McLain [log in to unmask]