Prior to the Eras Tour, Swift approached touring a bit lackadaisically, “like a frat guy,” she told the magazine. When it came to Eras, however, she began training six months ahead of time, running on the treadmill and “singing the entire set list out loud” daily—“fast for fast songs, and a jog or a fast walk for slow songs.”

She also completed a specialized program her gym crafted for her involving strength training, conditioning, and weight-lifting—plus three months of dance practice.

“I wanted to be so over-rehearsed that I could be silly with the fans and not lose my train of thought,” she said.

Surprisingly, Swift said choreography is not her strong suit. So she worked with choreographer Mandy Moore, recommended to her by friend and actress Emma Stone. Stone trained with Moore ahead of her role in the six-time Oscar-winning musical movie La La Land, which debuted in 2016. 

Swift also stopped drinking, with one exception: Grammy night.

“Doing that show with a hangover—I don’t want to know that world,” she told Time.

Also essential to her routine: rest.

After playing a series of shows, she takes an entire day to recover, leaving bed only to get food, then returning to her bed to eat. “It’s a dream scenario,” she said.

Such lavish breaks help sustain her through the next series of shows, despite any sickness, injury, heartbreak, discomfort, or stress the pop icon may be experiencing.

“That’s part of my identity as a human being now,” she said. “If someone buys a ticket to my show, I’m going to play it unless we have some sort of force majeure.”