I've never taken my blood pressure post ride. Been dizzy after standing up quickly post ride many, many times for may years. I try to remember because I could pass out, fall over and hit something but I've just figured that was a part of being in shape and exercising. And this has been a fact of life for me for so long that think I would have seen the adverse consequences long ago if they were there. (The elevated pulse. Likewise. It often takes me several hours for it to go down. Hard rides and it is still up when I go to bed. If it's up in the morning, I need a rest day.(Or a low gear easy spin.)