Forgot the point of my story was during my PMR and Cardiology visits they scheduled a stress test. I looked up the stress test and they use the Bruce Protocol. So I thought I will just start training for the test by working that into my treadmill routine. I idea is to go to 80% of your maximum heart rate. Your maximum heart rate is 220-your age. Thats how they do the test. I think my number is around 120, I can go 15 min before reaching 120,