Yesterday I had my blood pressure measured in one of those machines with the tight arm-cuff found in drugstores. I d been walking briskly around the store before I used the machine. I was shocked by the numbers! My systolic pressure was elevated, and my diastolic was VERY elevated! I waited a few minutes, then did it again and both numbers were PERFECTLY NORMAL. I asked a pharmacist how accurate the machine was, because this seemed weird, especially since only a month ago, I had my BP taken by my doctor and it, too, was normal. The pharmacist said to sit for another minute and take a THIRD reading, then go with whatever 2 out of the 3 readings indicated. I did that, and the third reading was also normal. I felt very good about that. However.... I m concerned whether my BP rises to dangerous levels when I m exercising. It s great that it s normal and healthy when I m sitting around doing nothing, but why was it so high, albeit TEMPORARILY, just from walking briskly in the store? P.S. Don t worry -- I won t use Yahoo Answers as a substitute for medical advice. :) However, I can t get to the doctor for a few days, so I thought I d post this on Yahoo in the meantime. Thanks to all 4 folks below for thoughtful, helpful info. :) You all made me feel better. FYI, no, I do NOT exercise regularly, unfortunately. I really ought to start. I m very slim, but I m not at all cardiovascularly in shape . Anyway, I don t want to have to choose among you, so I m going to let this question go into voting. Good luck, and thanks again! :)