Can You Sing a Song While Sprinting on a Treadmill Like Taylor Swift? Here’s What It Means About Your Fitness

Commanding the attention of football stadiums full of people by dancing and singing night after night takes serious charisma and talent. But the human body powering it all also needs to have a ridiculously efficient cardiovascular system in order to hit those notes while strut-dancing for hours.

In her recent Time Person of the Year profile, Taylor Swift explains how she prepared for the more than 150 nights of three hour shows she has performed across the globe for her Eras tour.

“Every day I would run on the treadmill, singing the entire set list out loud,” Swift told Time. “Fast for fast songs, and a jog or a fast walk for slow songs.”

What’s behind the multi-tasking? It’s actually a tried and true training technique for pop star performers and people like Broadway cast members who have to be constantly moving and dancing while singing. Mick Jagger—famous for dancing and strutting during live performances with The Rolling Stones—specifically keeps up a cardio routine for stamina. In a 2000s reality TV competition series to cast Elle Woods in Legally Blonde: The Musical, would-be Elles had to display their singing chops while sprinting on a stationary bicycle.

“Imagine doing cardio and basically slowly holding your breath, because when you’re singing, you’re just holding your breath and slowly releasing air; you’re not able to breathe in and out constantly,” explains singer and vocal coach Taylor Ann Winn. “You can’t have any level of shallowness in your breath when you’re singing or else you won’t be able to produce that note.”

From a singing standpoint, what you’re working on when you’re singing while running or doing some other form of cardio is your diaphragm, the muscle underneath your lungs that helps control your breathing. Professional singers utilize their diaphragm, which takes both practice and strength.

“So why cardio is so important for singing is that as [the diaphragm] becomes stronger and stronger, you have more capability of breath support and longevity of notes because everything that you’re doing when you’re singing—whether it’s holding a note longer, tonality of a note, agility of the voice—that’s all through breath,” Winn says.

Basically, as a performer, doing intense cardio like dancing needs to feel as easy as walking. And your diaphragm needs to be conditioned to work hard under stressful circumstances. Which is why singing on a treadmill is actually perfect preparation for a record-breaking world tour.

What it means if you can sing while running

While controlling the breath with a strong diaphragm is key, a mega star also needs to have enough oxygen in her lungs to power those notes, which certified personal trainer Teddy Savage, who is the national fitness lead at Planet Fitness, describes as lung capacity. It’s a quality Savage says Swift seems to have in spades.

“Her lung capacity is higher than what the average person’s lung capacity, who isn’t doing a lot of things, may be,” Savage says. “It is naturally strengthening her lungs and her body and her diaphragm to be able to do what she’s doing on that treadmill.”

If you too sing along to Midnights on the treadmill, you can pat yourself on the back for your “lung capacity, stamina, and respiratory endurance,” as Savage describes it.

“[Lung capacity shows] how quickly you can get back to a point where you can start moving again in a way that you would like,” Savage says. “That’s a really good determinant in terms of stamina [and endurance]. We’re all humans. We’re not machines, so we’re going to fatigue. It’s about how quickly you can get back to a point where you can start your next set or your next lap or your next rep, and that’s really what lung capacity and endurance boils down to.”

At the same time, if you’re not a pop star, singing and sprinting is not necessarily something you have to aspire to. Savage says to focus on the “perceived exertion” of an activity, which you can measure by checking whether you can hold a conversation while doing that activity. If you want to work on your endurance, incorporate interval bursts where you push yourself past the point of being able to talk, and then slow down and catch your breath.

Finally, while what Swift’s been doing may seem fancy, in actuality, it’s a very functional way for her to be training, meaning that it mimics something she does in her everyday life, since her job requires her to dance, strut, and sing. For most of us, there’s no need to belt out “Bejeweled” while sprinting except for the joy of it. Instead, do as Swift does and make exercise work for the needs of your own life.