People appear to be happier when they work out with music in their ears. This emotional response helps boost performance. (Creative Commons)

During the last two Summer Olympic Games, the world had a chance to see what motivated swimming champion Michael Phelps before a big race--listening to his iPod.

Phelps, like many athletes, is rarely seen without his white Apple headphones. In an interview with Time, he said that music helps him to “tune everything out.”

Recently, a great deal of psychological, physiological, and neurological research has focused on the effects music has on exercise. And from professional athletes such as Phelps to the average gym-goer, people tend to agree that music has stimulating qualities that result in a better workout.

Last year, a group of scientists in England did an investigative study of 12 male students. Each student listened to six songs, deemed “popular” by the scientists, during a 25-minute cycling test. They repeated this test, using the same songs, on three different occasions.

The songs, however, had different tempos during each test. In the first test, the original song tempos were kept the same. In the second test the tempos were increased by 10 percent, while in the third test the tempos were decreased by 10 percent.

According to the outcome of the study, speeding up the tempo resulted in an increase in distance, power and pedal cadence during the given time. On the other hand, slowing down the tempo caused a decrease in these same components. In addition, almost all of the men responded that they enjoyed the workout more with the faster tempo music.

However, some scientists believe that this increase in physical performance is little more than an emotional response.

Dr. Len Kravitz, a researcher at the University of New Mexico, said different studies over the years have reported conflicting conclusions.

“Studies investigating the effects of music on exercise performance have revealed inconsistent data,” he said.

Kravitz is hesitant to believe that any of the data published thus far presents conclusive evidence indicating the connection between psychological or neurological processes and exercise performance.

In addition, another study in 2004 determined that music only helps athletes doing less vigorous exercises. According to the study, people using 90 percent of their maximum oxygen uptake do not benefit from music.

But, whether music has psychological effects on the brain or not, the emotional effects are undisputable.

Simply stated, people seem happier when they are listening to music. It’s now almost a rarity to see people working out without the accompaniment of an mp3 player.

During the last decade, Nike created an entire blog on their national website dedicated to music that is popular to listen to during workouts. Called the SportMusic Blog, this site includes articles about particular genres of music and highlights the favorite songs of professional athletes, such as Serena Williams.

Nike coined the term “PowerSong” to describe songs and playlists that have the ability to “pump up” athletes. On iTunes, Nike has their own page, called Nike Sport Music, where they advertise PowerSong Mixes and allow people to create and share their own Sport iMixes.

Fitness centers are also buying into the music craze, playing music through overhead speakers or purchasing workout equipment capable of connecting to iPods and mp3 players.

Scientific or not, the trend of people listening to music while they workout is certainly increasing and not likely to fade from popularity in the near future.

Reach staff reporter Rebecca Buddingh here.

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The Popular PowerSong Playlist:

1) Good Life – Kanye West Feat. T-Pain (a Serena Williams favorite)

2) Public Service Announcement – Jay-Z (a Tom Brady favorite)

3) Dani California – Red Hot Chili Peppers (a Lance Armstrong favorite)

4) I’m Me – Lil’ Wayne (a Michael Phelps favorite)

5) Don’t Stop the Music- Rihanna (Nike PowerSong Mix)

6) Lose Yourself – Eminem (Nike PowerSong Mix)

7) Eye of the Tiger – Survivor (Nike PowerSong Mix)

8) Pump It – Black Eyed Peas (Nike PowerSong Mix)

9) Day ‘n’ Nite – Kid Cudi (Nike PowerSong Mix)

10) A-Punk – Vampire Weekend (Nike PowerSong Mix)