Those of us who have experimented with high intensity exercise quickly learn, that time, short as it may be, is punishing. Many people find the experience aversive, said Matthew Stork, a graduate student at McMaster University in Hamilton, Ontario, who led the new study, published in Medicine & Science in Sports & Exercise.
Stork and his colleagues at McMaster, who have conducted many studies of high-intensity interval training, wondered if it would be possible to find ways to modify peoples perceptions of how little they were enjoying the exercise. You cant reduce the actual intensity substantially, he knew, without reducing the physiological benefits. But perhaps you could alter peoples feelings about the difficulty.
He and his colleagues thought immediately of music. They recruited 20 young, healthy adult volunteers, none of whom previously had dabbled with high-intensity interval training. Then he brought them into the lab and had them learn how to work out hard.
The precise regimen that the volunteers followed was simple enough. Using stationary bicycles, they completed four 30-second bouts of what the researchers call all-out pedaling, at the highest intensity that each volunteer could stand. Each 30-second bout was followed by four minutes of recovery time, during which the volunteers could pedal gently or climb off the bike and sit or walk about. Throughout the all-out intervals, meanwhile, the scientists tracked the volunteers pedaling power output and asked them how hard the exercise felt and whether they were having fun. Or not.
After that workout, the volunteers sat down and listed their favourite songs, which the researchers then downloaded and used to create custom playlists for each volunteer.
Then each volunteer returned twice more to the lab, grunting through two additional sessions of the high-intensity intervals. During one, they listened to their chosen playlist. In the other, they did not listen to music.
Afterward, the researchers compared the riders power outputs and reported feelings about the workouts difficulty.
The volunteers all reported that the intervals had been hard. In fact, their feelings about the difficulty were almost identical, whether they had been listening to music or not.
What is interesting is that their power output had been substantially greater when they were listening to music. They were pedaling much more ferociously than without music. But they did not find that effort to be more unpleasant. Without music, the workout struck them as about the equivalent of an eight or higher on a zero to 10 scale of disagreeableness (with 10 being unbearable).
With music, each interval still felt like about an eight or higher to the riders, but they were working much harder during each 30-second spurt. The intensity increased but not the discomfort.
Polled by the scientists at the end of the experiment, all 20 riders said that if they were to take up interval training on their own after the study, they definitely would listen to music to get themselves through the workout.
How music affects performance and perceptions during intense exercise remains unclear, Stork said, but it likely involves arousal responses. The body responds to the rhythm of the music with a physiological revving that prepares it for the demands of the intervals.
People may also turn to music in hopes of ignoring their bodys insistent messages of discomfort. Music cannot, of course, override those messages altogether, Stork pointed out. But it may mute them and make you more eager to strain through another session of intervals, sweat and playlist streaming.
- Gretchen Reynolds