“Nothing has given me more mental confidence than being able to move direct from room temperature into the chilly,” Dorsey says.” [E]especially in the morning, moving into an ice-cold tub from just being hot in bed is — it only unlocks this thing in my mind and I feel like if I can will myself to do this thing that appears so little but hurts so much, I could do nearly anything.”
By CNBC:

Twitter and Square CEO Jack Dorsey (42) walks 5 mph daily, eats just one meal a day, fasts all weekend, and attempts to meditate two hours a day. CNBC looked at 11 of the”wellness” customs, which he spoke on a recent episode of this Ben Greenfield Fitness podcast.