SoulCycle has amassed a devout national following, driven by their use of music to fuel intense indoor bike workouts. Biking to the beat not only feels good, but studies galore have proven time and again that music — especially music with a driving beat — can improve your ability to work out more efficiently. Costas I. Karageorghis, Ph.D, professor of Sport & Exercise Psychology at Brunel University in London and author of “Applying Music in Exercise and Sport” has conducted a bunch of them.

“Music has a sort of a metronome effect (on exercise),” explains Karageorghis. “If I were to use an analogy, imagine we're in the suburbs of New York and we're driving into the center of the Financial District (which is in lower Manhattan). Every time you get to an intersection, it’s a green light and you can fly straight through without having to stop and waste time and fuel. That's the sort of effect that music can have over time. It can spread out your effort and make you more efficient. The gain of efficiency when using music synchronously (with exercise) is around 6 to 7 percent in continuous rhythmic-type activities, such as running, walking, cycling indoors, or working out on a rowing machine.”

Karageorghis says this is due to something called the “entrainment mechanism,” where different “pulses” within the body tend to entrain to the rhythmical qualities of the music. “When I say ‘pulses,’ it might be the respiratory rates, it might be the heart rate, and it might be brain waves,” he explains.

No wonder people think SoulCycle is such a great workout. The rhythm, or beats per minute (BPM) of the song you choose almost literally fuels your routine — but to a point. “Everyone assumes, the harder you work out, the faster the music should be. But I found there to be a ceiling effect at around 140 beats per minute. If you speed music up beyond that while you're working harder and harder, there’s no associated benefit,” says Karageorghis. “One reason is that most recorded music is around 105 to 135 BPM, so we develop a familiarity towards that, and there can be a negative aesthetic response to music faster than 140 BPM.”

And, along with a driving rhythm, the simpler the lyric or piece of music, the better. It's very hard to engage in syntactic processing — to process lyrics — at very high intensities of exercise, explains Karogeorghis. “Beyond 75 percent of aerobic capacity, your brain is forced to process what we call ‘interoceptive cues,’ or fatigue-related signals that travel from the working muscles to the brain,” he says. This is also why Karageorghis discourages outdoor cyclists from using music the same way — it can be a little too distracting.

Music can boost your workout in more ways than just efficiency. Karageorghis says it can be used as a “psych-up tool” before working out, to reduce anxiety before a particularly stressful event or championship, to enhance your mood while it's playing in the background (even without consciously synchronizing to it), to expedite your recovery at the end of a workout, and even between bouts of exercise such as HIIT, or high-intensity interval training, to assuage the negative emotions that one experiences during the high intensity form of activity — as long as it’s a little more mellow than the music heard during the workout.

“You might think, intuitively, with a high-intensity type physical activity such as HIIT, that you would need relatively high-tempo music during the recovery bouts, but what we have found is that it's actually medium tempo music that results in the best psychological responses during recovery,” Karageorghis explains.

What’s more, music literally mutes your sense of fatigue during and after you work out. “When music is playing, the regions of the brain that are responsible for communicating fatigue are somewhat inhibited,” he says. “This might explain why, when people exercise and listen to music, they experience such a reduction in perceived exertion and an elevation in our mood.”

During one of his studies using electroencephalography (EEG) to measure electrical activity in the brain, Karageorghis noticed how clusters of neurons in the brain fire in response to music during exercise. Though each cluster of neurons fired with a slightly slower frequency, they’d fire with greater amplitude. “It seems that when we're working out with music, neurologically, there is less conscious effort required to produce whatever motor pattern you’re engaged in, be it running, cycling, swimming, walking, or whatever,” he says.

This feeds into Karageorghis’ theory: “Owing to a psychological phenomenon known as the ‘affective memory,’ which is how we remember feeling, we're more likely to stick to an exercise routine if we remember it as positive,” he says. “Similarly, there's another phenomenon called ‘affective forecasting,’ which is how we predict we're going to feel. This is an approach that I've been testing systematically to see whether making the exercise experience more pleasurable is likely to result in people adhering to exercise regimens, and benefiting from habitual physical activity.”

A science-backed workout playlist for summer

To help us get moving, Karogeorghis shared a selection of recent songs that fall within the ideal workout window of 120-140 bpm, or beats per minute. He says: “I think it was William Congreve who said, ‘Music has charms to soothe the savage beast.’ It certainly has charms to soothe the savage workout.”

“Go Bang,” by PNAU

“There is an energizing feel to this track and the lyrics will help you to immediately enter ‘the zone,’” he says. “She ran past the limit, We come past the limit to flow.”

“If I Can’t Have You,” by Shawn Mendes

A captivating groove raises your spirit and the sing-along lyric, with its strong dissociative qualities, takes your mind right off the pain,” Karageorghis says.

“Bibia Be Ye Ye,” by Ed Sheeran

“With faint echoes of Paul Simon’s ‘You Can Call Me Al,’ this is a feel-good track for a new generation. Your mood will be totally elevated and nothing can stand in your way,” he summarizes.

“Can You Feel It,” by Tiesto & John Christian

Karageorghis says, “If you want to place your foot firmly on the accelerator, this pulsating dance track will turbocharge your workout with a thoroughly immersing interplay of synthesized sounds.”

“Sweet But Psycho,” by Ava Max

“For the apex of your exercise routine, when you want to push yourself real hard, Ava Max’s immersive smash hit is sure to take you to the max,” Karageorghis says.

CORRECTION (July 29, 2019, 4:51 p.m. ET): A previous version of this article misstated the gain of efficiency when exercising with music. It is 6 to 7 percent, not 67 percent.

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