Wim Hof tought hmself how to control his heard rate and blood circulation through breathing techniques. Some of the tests I find fascinating about Wim: Climbing Everest in nothing but boots and shorts, running a half marathon barefoot above the Arctic circle in only shorts.
The Joe Rogan Podcast: Joe interviews a lot of people I find very interesting. A few of my favorites:
#737 with Lance Armstrong
#712 with Wim Hof
#752 with Mark Sisson
#553 & #740 with Thaddeus Russell