I have syncope which really isn't a big deal if I wanted to sleep all the time. Syncope means I faint or black out when I stand or when I do something that should raise my blood pressure even slightly. This is caused by a series of events that all come from hypotension, or low blood pressure. This is the short definition of course. Either way, it doesn't happen every single time. When I decided to lift weights was when I became very aware of my syncope. I just cannot get my heart rate up consistently to get a good workout in. Not to mention I looked odd constantly yawning while lifting. It's almost like I could take a nap between every rep. It's annoying more than anything. So I wanted to learn to train my heart to do it's job. When you run with syncope it takes a very very long time to get your heart rate up and once it gets up, you could run forever. Of course you may pass out repeatedly trying to get your heart rate to that point. That's the miserable way to do it. The better way to train syncope is to walk then run and walk then run. Over time, you walk less and run more. This is the best way to train your heart rate for anyone but especially for those with syncope. It keeps your heart guessing and trying to keep up until finally, it figures out it's just going to have to raise on demand. So for those of you out there with super low blood pressure and heart rates and for those of you who faint or blackout when you do anything strenuous, it takes time but you CAN get there!