The systolic (1st number would go up), the diastolic (2nd number, the pressure against the arterial walls during the rest period of the heart) should stay the same. A temporary raise in systolic is okay, in fact it goes up when you exercise. If you have a high diastolic, you have hypertension already. If your blood pressure is under control normally, playing poker should not adversely affect you, unless you already have high blood pressure. It all depends on what your blood pressure usually is.... but I could be wrong. If I am, I am sure someone will correct me. I made a similar post probably about a year ago, you might be able to find it; nobody really had an answer at the time, but my husband Brian is a research hound and found the answer on his own. Basically, he determined that he needed to control his blood pressure anyway and as long as he did that, it was fine to play poker. He did it with diet and exercise and he is off meds now. I am very proud of him... plus I like to watch him polish his guns!