Can relate (minus meeting Wim): when going to the spa, I alternate between sauna and submerging in ice water for 60-90 seconds. My BPM goes from 150 to ~35 in t

Can relate (minus meeting Wim): when going to the spa, I alternate between sauna and submerging in ice water for 60-90 seconds. My BPM goes from 150 to ~35 in that time. Climbing out of the cold water and laying down on the chair induces such calm in my mind... Have to do this more often. Also makes me feel warm in cold weather.