Pranayama is nothing more than a regulated breathing exercise - there is no god and no religion. Considering how powerful it is, it is also the most under-rated health alternative on the planet.
I've toyed with Pranayama many years back when I got curious with what the books were all saying - that Pranayama should only be practised with the assistance of learned Pranayama teacher or risk getting seriously messed-up. Since I had no Pranayama teacher, I did it on my own, almost with reckless abandon, spending half the day doing all the Pranayama exercises on a book. It was a good thing I was already strong in my yoga practice and on top of my fitness game. What followed can only be described as a Superman-effect that lasted 2 weeks! It would seem like I've tapped into an undepletable reservoir of energy. I did things I thought were not humanly possible. The energy surge was such it felt like I would explode - a lesser fit individual may not have fared as well. It got me scared I never did it again with such intensity. I know now, why it needs to be dealt with, with utmost care and reverence.
Now, I moderately integrate it in my yoga practice - lightly tapping into it like a vitamin supplement. With regular Pranayama, I sometimes feel like a raging locomotive. I don't take any medication whatsoever and I can't remember the last time I saw a doctor. When I face-planted on a 22ft cliff dive, my quick recovery was amazing.
I began to wonder...how could the air we breathe, something so free, so accessible and so abundant be so powerful? And why is this on-tap power largely ignored? I'm not an expert in this field, but I've done enough of it to know how powerful it is. Same reason I integrate this into my yoga class.