By GRETCHEN REYNOLDS
For a study published last year, British researchers asked 12 healthy male college students to ride stationary bicycles while listening to music that, as the researchers primly wrote, “reflected current popular taste among the undergraduate population.” Each of the six songs chosen differed somewhat in tempo from the others.
The volunteers were told to ride the bicycles at a pace that they comfortably could maintain for 30 minutes. Then each rode in three separate trials, wearing headphones tuned to their preferred volume. Each had his heart rate, power output, pedal cadence, enjoyment of the music and feelings of how hard the riding felt monitored throughout each session. During one of the rides, the six songs ran at their normal tempos. During the other rides, the tempo of the tracks was slowed by 10 percent or increased by 10 percent. The riders were not informed about the tempo manipulations.
But their riding changed significantly in response. When the tempo slowed, so did their pedaling and their entire affect. Their heart rates fell. Their mileage dropped. They reported that they didn’t like the music much. On the other hand, when the tempo of the songs was upped 10 percent, the men covered more miles in the same period of time, produced more power with each pedal stroke and increased their pedal cadences. Their heart rates rose. They reported enjoying the music — the same music — about 36 percent more than when it was slowed. But, paradoxically, they did not find the workout easier. Their sense of how hard they were working rose 2.4 percent. The up-tempo music didn’t mask the discomfort of the exercise. But it seemed to motivate them to push themselves. As the researchers wrote, when “the music was played faster, the participants chose to accept, and even prefer, a greater degree of effort.”
The interplay of exercise and music is fascinating and not fully understood, perhaps in part because, as a science, it edges into multiple disciplines, from physiology to biomechanics to neurology. No one doubts that people respond to music during exercise. Just look at the legions of iPod-toting exercisers on running paths and in gyms.
In fact, it’s music’s dual ability to distract attention (a psychological effect) while simultaneously goosing the heart and the muscles (physiological impacts) that makes it so effective during everyday exercise. Multiple experiments have found that music increases a person’s subjective sense of motivation during a workout, and also concretely affects his or her performance. The resulting interactions between body, brain and music are complex and intertwined. It’s not simply that music motivates you and you run faster. It may be that, instead, your body first responds to the beat, even before your mind joins in; your heart rate and breathing increase and the resulting biochemical reactions join with the music to exhilarate and motivate you to move even faster. Scientists hope to soon better understand the various nervous system and brain mechanisms involved. But for now, they know that music, in most instances, works. It eases exercise. In a typical study, from 2008, cyclists who rode in time to music used 7 percent less oxygen to pedal at the same pace as when they didn’t align themselves to the songs.
But there are limits to the benefits of music, and they probably kick in just when you could use the help the most. Unfortunately, science suggests that music’s impacts decline dramatically when you exercise at an intense level. A much-cited 2004 study of runners found that during hard runs at about 90 percent of their maximal oxygen uptake, a punishing pace, music was of no benefit, physiologically. The runners didn’t up their paces, no matter how fast the music’s tempo. Their heart rates stubbornly stayed the same, already quite high, whether they listened to music or not. That result, according to a 2009 review of research by Costas Karageorghis and David-Lee Priest, researchers who have extensively studied music and exercise, is likely due to the ineluctable realities of hard work. During moderate exercise, they write, music can “narrow attention,” diverting “the mind from sensations of fatigue.” But when you increase the speed and intensity of a workout, “perceptions of fatigue override the impact of music, because attentional processes are dominated by physiological feedback.” The noise of the body drowns all other considerations. Even so, about a third of the runners in the 2004 study told the researchers that they liked listening to the music, especially at the start of the run. It didn’t increase their speed or make the workout demonstrably easier. But it sounded nice.
And that result, obvious as it seems, may be the ultimate lesson of how and why music is effective and desirable during exercise, says Nina Kraus, a professor of neurobiology at Northwestern University in Illinois, who studies the effects of music on the nervous system. “Humans and songbirds” are the only creatures “that automatically feel the beat” of a song, she said. The human heart wants to synchronize to music, the legs want to swing, metronomically, to a beat. So the next time you go for a moderate run or bike ride, first increase the tempo of some insidiously catchy music to your taste and load them on your iPod. “Our bodies,” Dr. Kraus concluded, “are made to be moved by music and move to it.”
