Do you have a workout playlist? You may find yourself matching the stride of your power walk to the beat in your earbuds—but tempo isn't the only thing affecting how fast you go. Certain musical pieces seem to make people take longer strides, even while walking to the same beat. (Spoiler alert: Aqua.)
Marc Leman is a musicologist at Ghent University in Belgium. With his colleagues, he created a list of 52 songs with a tempo of 130 beats per minute, a speed they chose based on previous research. The playlist included a variety of genres, and all the songs were in 4/4 time.
Then the researchers gathered 18 "normally built" adults, strapped sensors to their legs, and sent them walking laps around a gymnasium. The subjects were explicitly told to walk in time to the beat of the music. Through headphones, they heard 30-second clips of the different songs, with periodic interludes of only a metronome sound.
Although all the music had the same tempo of 130 beats per minute—which subjects stepped in time with—their actual walking speed varied as they took longer or shorter strides. Leman says that to certain songs, people walked 10 percent faster than they did to others (or to the metronome beat).
The researchers dubbed the fastest-walking songs "activating," and the songs that made people walk slowest "relaxing." The full playlist is here, ranked from most relaxing to most activating. These were the top 10 most relaxing songs, to which walkers made the least forward progress:
And here are the tunes to which people covered the most ground:
Right around the middle was "Dragostea din tei," better known by some as "the Numa Numa song." Test subjects probably got slowed down by the requisite arm flailing.
Separately, the researchers asked subjects to rate the musical selections on a variety of adjectives: Was the song happy or sad? Tender or aggressive? Known or unknown to the listener?
Some of the responses were tied to how speedily the songs made them walk. For example, pieces described as "stuttering" rather than "flowing" made people take shorter strides. Pieces that subjects found especially "aggressive" or "loud" (although the volumes of all the songs had been matched in their headphones) made people walk faster. So did songs they described as "bad" rather than "good." (This may explain "Barbie Girl").
The musicologists, meanwhile, tried to find more scientific explanations for the powers of certain songs. Leman says this was surprisingly difficult. They did find that more activating songs tended to have simpler melodies, with fewer notes per beat. These pieces often had a strong bass line, as well as clear downbeats ("one two three four..."). The group is still working on figuring out what kinds of music make people move the fastest.
For his own exercise playlist, Leman is a fan of jazz, though he says it's not always great at getting a person moving. He thinks syncopation, which interrupts the regular beat of the music, is an important factor in making a piece relaxing rather than activating. Instead of marching straight ahead, syncopated jazz music seems to encourage you to walk with more horizontal motion, Leman says: "You want to swing." Image: by Malingering (via Flickr) Marc Leman, Dirk Moelants, Matthias Varewyck, Frederik Styns, Leon van Noorden, & Jean-Pierre Martens (2013). Activating and Relaxing Music Entrains the Speed of Beat Synchronized Walking PLOS ONE DOI: 10.1371/journal.pone.0067932