If you think those pumping, thumping, numbing dance mixes of Celine Dion's "Taking Chances" or Rihanna's "Don't Stop the Music" provide a banal background sound at your favorite workout center, think again.

It only appears as if they were put in place to annoy.

Workout centers and their incorporation of music, whether it's classic KISS, current Kanye West or a dance-friendly Dion, are seen as an important part of the exercise experience as drinking water and stretching.

It's all about getting physical to the right beat.

"It's a big deal, and it's a real thing with our industry," says Craig Ramage, general manager at the new St. Louis Fitness Factory. "If you don't think so, go into a club where there's no music, and all you hear is the sound of the machines. It's so bad.

"The energy is down and people are less likely to talk to one another because everyone can hear what you're saying, like you're in church," Ramage says. "The music is like another character in the place, another employee. Every club has to have it, and it's one of the things people will give their opinion of the most."

Diane Lane, group exercise manager and yoga instructor for St. Louis area Bally Total Fitness clubs, says, "Music is everything. It's the motivator. You can have a really good instructor or even an only average instructor, but if the music is pumping and full of energy, the class will respond."

Various studies speak to the correlation between working out and music. Men's Health magazine says listening to your favorite music while working out will push you harder, make exercise more fun and is more likely to make you stick to a routine.

Other experts say music helps athletes get into their zone, offering them flow, control and focus, while also allowing them to manage the painful stress they're putting their bodies through.

Medicinenet.com says upbeat music increases a workout's speed and intensity and that music in general while working out improves fitness, commitment and enjoyment. A study by Ohio State University says listening to music while exercising even provides a cognitive boost.

Many clubs rely on satellite radio for their general population. "Some will come to the club and listen to whatever's playing. I don't want to call it elevator music," Lane says.

"We bounce around with (dance) club music, and we go through Muzak. The main problem with that service is a lot of it is European, songs nobody knows. It's high energy for sure, but sometimes people prefer songs they know rather than high energy," Ramage says.

He adds that "with every seven good songs, there's one weird one in there because a computer told them it fits into a category. You're working out and your body's reacting and suddenly there's a Eurotrash remix of Celine, and it's a total downer."

Kim Mason, an assistant manager at St. Louis Fitness Club, says it plays "90s alternative music, with acts like Alanis Morissette and Mazzy Star. "We have people in our teens to seniors, so we try to find something generic enough to please most people."

Music gets more specialized in exercise classes such as spinning, stepping and aerobics. "All of our classes use music," says Mason, who can't get the workout she needs without music. "That definitely motivates you and keeps you going. It's very important."

When Mason is on the treadmill, she finds her pace picks up if she's listening to a song by Prodigy or Salt-N-Pepa. "I lean toward the dance and house music for cardio, and something more hard core for weight lifting, because it makes me feel like a bad ass," she says.

Lane says workout music should essentially "match the ride. If you're doing sprints, it should be fast. If you're doing a hill or climbing, the music should be slower to really simulate a climb."

One spinning instructor at Bally Total Fitness uses jazz, Lane says. Another uses disco. Music can vary with weight lifters depending on the movement. Enya and Kenny G. may easily find their way into yoga instruction.

Fred Massingale, 49, is an Internet technology manager who works out at Bally Total Fitness in Clayton. He is one of an increasing number of gym rats who brings his own music to the workout center via an MP3 player or iPod.

He says there's nothing wrong with the club's tunes, but "the volume fluctuates where sometimes it's too loud and sometimes it's too low. I bring my own so I can be my own DJ."

Depending on his workout, Massingale likes to switch among Beyonce, Common, Robin Thicke, Jill Scott and Petey Pablo.

"Any club you come into, half the people will have their headphones on," Mason says.

Ramage adds, "The MP3s are taking over everything. We have people who ask us to turn down the music in the club so they can hear their iPod better. Wow. I didn't have to deal with that six or seven years ago."

Lane says a personal player is OK as long as it isn't disruptive. If an instructor has set up a workout to certain music, "we wouldn't encourage it in a cycle class," she said. "It's courteous to pay attention."

When you're ready to get physical, participants say listening to upbeat music will spice up a workout. Most gyms provide the beat, but many on the machines let their iPods help with the heavy lifting.

Music can pump you up and let you show your heavy mettle.

These songs are good for step, high-low and strength training workouts.

-Britney Spears, "Lucky"

-Justin Timberlake, "SexyBack"

-Rihanna, "Hate That I Love You"

-Shakira, "Beautiful Liar"

-Beyonce, "Check on It"

-Yuna, "Buttons"

-Kelly Clarkson, "Because of You"

-Britney Spears, "Gimme More"

-Justin Timberlake, "My Love"

-Metallica, "The Unforgiven"

-3 Doors Down, "Loser"

-U2, "Beautiful Day"

-3 Doors Down, "Kryptonite"

-Godsmack, "Shinedown"

-Kelly Clarkson, "Walk Away"

-Nirvana, "Smells Like Teen Spirit"

-Daft Punk, "One More Time"

-ABBA, "Dancing Queen"

-Def Leppard, "Pour Some Sugar on Me"

Certain songs just aren't supposed to line up next to one another. That's especially true with some of my iPod workout music. But this music shares its ability to keep my adrenalin flowing. Here are some favorites.

-Kanye West, "Stronger"

-Nine Inch Nails, "March of the Pigs"

-Smashing Pumpkins, "Bullet With Butterfly Wings"

-OutKast, "Bombs Over Baghdad"

-Destiny's Child, "Lose My Breath"

-Public Enemy, "Welcome to the

Terrordome"

-Hole, "Violet"

-Marilyn Manson, "The Beautiful People"

-Sean Paul, "Get Busy"

-Michael Jackson, "Wanna Be Startin' Something"