Twitter CEO Jack Dorsey discussed his lifestyle habits in a recent podcast interview, in which the billionaire divulged subjecting himself to starting every morning with an ice bath, eating one meal per day, and fasting on weekends.

Twitter CEO Jack Dorsey recently appeared on the Ben Greenfield Fitness podcast where he described his meditation retreats and general lifestyle, which included starting each day with an ice bath, and then eating only one meal per day.

“Nothing has given me more mental confidence than being able to go straight from room temperature and into the cold,” said Dorsey, “just making that switch, especially in the morning, when I’m going into an ice-cold tub, from just being warm in bed — it just unlocks this thing in my mind.”

“Now, all my showers are cold showers, I just don’t do hot anymore,” continued the Twitter CEO, “for me, it’s been better than caffeine in terms of waking me up and focusing me. It’s also something I have to overcome every single day, like, ‘do I really have to do this? Yes, I’m going to do it.'”

In terms of diet, Dorsey said “this is where I also experiment a ton — both in terms of what I eat and when I eat.”

“For the past two years, I’ve only had dinner,” said Dorsey, explaining his one meal per day, “I usually eat around 6:30, and I eat until about 8:30 or 9:00 at the latest, and that’s when I can also drink wine.” Dorsey also added that he fasts on weekends, not eating any meals.

The Twitter CEO added that he drinks 28 ounces of water after he wakes up, and continues drinking water throughout the day, until it’s time for his one “really big meal” for dinner, which consists of protein — fish, chicken, or steak — a big salad, vegetables, and mixed berries or dark chocolate for dessert.

Dorsey added that he also walks, “rain or shine,” five miles from his home to his office, three days a week.

“Every day I was walking into work, I’d wake up at around 6:15, I would meditate for an hour, I would get ready, I’d be out the door at 7:30, and then I’d be in the office by 9:00 AM,” said the Twitter CEO, adding that he will either listen to podcasts, audiobooks, or “just think” while walking to the office.

“And you know, an hour and fifteen minutes in five miles, it’s a pretty brisk pace,” continued Dorsey, “so I’m moving really fast — I’m in the sun, I’m directly walking into the sun — the way that my walk is organized — so I go directly into the rising sun, and I try to get as much sunlight as possible.”

“Over the past six months I decided that I needed a little bit more space to think, and I decided to work from home on Tuesdays and Thursday,” added Dorsey.

Dorsey also described his meditation retreats, which are ten-day experiments aimed at being able to control his reactions. The retreats consisted of self-deprivation in terms of electronic devices, reading, writing, eye contact, and talking, among other things.

“In my experiments, I love going to the extreme, and then kind of walking back a bit, just to find the balance,” said Dorsey, who then described what and when he was allowed to eat during his retreats, “it’s all vegetarian, you have breakfast and you have lunch, and you’re not allowed to eat after noon, tea at 5:00 PM.”

“Every day, I would wake up and I would look forward to two things, hot oatmeal and honey nut Cheerios,” elaborated the billionaire, “and there was one day, I remember, I think it was actually day seven when the oatmeal was cold, and I’m like, ‘Oh, man, this is is my one thing, this is the one thing I look forward to every single day.'”

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