She’s taking over the world, so why shouldn’t we mimic her exercise routine? In Time magazine’s Person of the Year article, Taylor Swift describes her physical training in preparation for her Eras tour. And you can see why she needed to train: Swift spends 3.5 hours on stage each show, belting out 44 songs. To prepare for that grueling nightly test, Swift describes sessions spent running on a treadmill while singing her set list. Likely perfectly in tempo, she runs fast for upbeat songs and slows down for ballads. The fancy word for this? Fartlek training, a specific type of interval training. Now that we’ve got the giggles out, let’s break it down.

What are the benefits of interval training?

Interval training refers to any workout in which you alternate between high- and low-intensity bursts of activity. Doing so, whether you rest fully between high-intensity bursts or keep going slowly between them, has many benefits, describes Rosalyn Salstrand, RCEP, a registered clinical exercise physiologist at Mayo Clinic. “Performing interval training can improve cardiovascular fitness and endurance, which can help an individual exercise at a higher intensity and for a longer time,” she says. “It can also improve various measures of cardiovascular health, including blood sugar, cholesterol, and loss of weight and body fat.”

How does someone who hasn’t done this before begin?

Start with walking! Work up to a moderate intensity pace that challenges your breath. This intensity would allow you to speak, but not sing. After 5 to 10 minutes, pick up the pace. Aim for high intensity — fast walking, jogging or running — for just 30 to 60 seconds. This short duration should feel difficult. Repeat the cycle as able, perhaps 2 to 3 intervals for first-timers.

How long does an interval have to be?

That depends on the intensity of the work. The American College of Sports Medicine describes a “sprint” interval as 30 seconds but can be performed longer. Running isn’t the only option, either. Salstrand shares that if running is a personal goal, then it’s likely the best method of training, but those high-intensity bursts can include an increase in speed, incline or resistance.

What is fartlek training and how does it differ?

Swift’s method of training sounds closer to fartlek training, which in Swedish means “speed play.” Fartlek training is a less structured type of interval training, and speed can be at the discretion of the runner, say to the tempo of a song. Unlike standard interval training, this type of running does not include a recovery time. You just keep going, although you slow to a pace that allows your heartrate to drop in between the harder bursts. Doing so makes sense when you’re working toward a big aerobic goal, such as running a three-hour marathon. Or singing on stage for even longer in front of 80,000 people. The preferred method? The one you enjoy most. To train like Taylor, just listen to one of her lyrics: “Run, like you’d run from the law.”