Hot meditation sessions

I have been taking a sauna most mornings for the last eight months. Since this mostly involves sitting around in a hot room I've started to use this time to meditate.

It takes about seven minutes for me to physically reach an equilibrium in the sauna. Once this happens I start my meditation focusing on my breathing. I can still find the calm place in my mind even though my heart rate is almost double my normal resting rate. My breathing is deeper than usual but still rhythmic, I draw the breath in through my mouth and exhale out my nose.

My breathing and heart rate settle at about the same level as a brisk walk but I'm sitting still. It feels like my brain is highly oxygenated from the increased blood flow. The physical symptoms make me feel exited or nervous except I detach from them and realize those feelings aren't real, they are only my mental justifications for what I'm physically feeling. When I get in deep the sensation boarders on euphoric, something like I imagine a “runners high” to be like.

I'm careful not to stay too long, and I have a whole safety procedure to make sure I don't cook myself so nobody needs to caution me about sauna use. Has anyone else tried meditating in unusual conditions? What are/were your results?