Kang Seung hyun, a teacher and former rugby player preparing for a fitness photo shoot, said his gym had elected to shut off the treadmills instead of enforcing the slow pace. The bikes, however, remained open for reasons he didn’t understand.
“So we can’t run or use the treadmills, but we can bike? It seems weird to me,” he said.
Ralph Yun, a CrossFit coach who has been teaching for the past five months, said listening to music at a similar pace to your heart rate could increase performance, but it doesn’t necessarily make you work out harder.
“You could be listening to slow music and exercising just as intensely,” he said.
Costas Karageorghis, a professor at Brunel University in London who has studied the effects of music on exercise for 30 years, was amused by the recommendations, calling them “ludicrous.”
“If people are motivated enough to work out at a high intensity, there’s nothing about the music that’s going to stop them,” he said.
That said, research has shown that music can significantly alter one’s workout, even if not in the way Korean authorities had intended.
Dr. Karageorghis said the sweet spot for aerobic exercise, like running on a treadmill or cycling, was 120 to 140 beats per minute. The music can distract the mind from feelings of fatigue, lowering your perception of how hard the body is working and improving your mood. Louder music, above 75 decibels, can intensify a workout, though very loud music creates the risk of hearing problems like tinnitus.
He said he was unsurprised the health officials chose 120 beats, as there has been research suggesting it was a “key cutoff” in some ways. It’s roughly twice the low end of a healthy resting heart rate, and 120 steps per minute is a common rate of walking, he said. Wedding D.J.s have told him they’ll use a 120-beat song to entice people onto the dance floor (Whitney Houston’s “I Wanna Dance With Somebody” checks in at about 120).