Bradley Walker has been singing country music since he was 3. When he was 4, he made his debut at a variety show. In his teens, he performed at dance halls, benefits and churches. Walker, who has nemaline myopathy, knew there was no better feeling than singing to an audience.

“If you love music, it never leaves you,” says the baritone. He pursued his passion relentlessly, eventually making an appearance on TNN’s “Nashville Now” with the Oak Ridge Boys. In 1989, he appeared on the national Jerry Lewis Labor Day Telethon, a feat he repeated in 2001 and 2002.

As country music changed, Walker discovered a love for bluegrass music, which led to bigger things. In 2002, he made his debut at the Grand Ole Opry with bluegrass group phenomenon IIIrd Tyme Out.

“I’ve been raised to not to let my challenges get in my way,” says the 47-year-old Athens, Ala., native, who believes in music’s therapeutic power, too.

“Music can move so many different emotions,” he notes. “It’s one of the most powerful things in the world. It puts a smile on my face. I don’t know what I’d do without it.”

Walker is negotiating a contract with Rounder Records, the nation’s premiere independent record label.

Bradley Walker on the Web: http://bradleywalker.com

Derrick Rivere of Houma, La., taught himself to play the piano when his father, also a musician, gave him a keyboard. Little did he know how crucial music would be in his life.

When he was 15, Rivere’s Duchenne muscular dystrophy caused respiratory failure.

“I was clinically dead when I arrived at the hospital,” he said. Though a tracheostomy kept him alive, Rivere became depressed. During his three-month rehabilitation, he discovered the hospital’s music therapy program, a music room with — of all things — a piano. It saved him in many ways.

I played for an hour each day,” Rivere, 33, recalls. “It was therapeutic. There’s something about a beat and groove that’s beyond words. It’s a release.”

The musician tells of a time in his 20s when he was invited on stage at a club. “The next thing you know I was playing six nights a week for two and a half years,” he says.

Rivere’s reggae band, Irie Vibrations, won a Big Easy Entertainment Award in the 1990s. They produced CDs and played the New Orleans Jazz Festival. Then the unforeseeable happened.

Hurricanes Katrina and Rita struck.

“Except for myself, everyone in the band lost everything,” says Rivere, who owns a home 40 miles south of New Orleans with his daughter. The group is on hold.

Not one to give up, Rivere tours with another band in Shreveport, La., now. “I feel more than blessed,” he says.

Derrick Rivere on the Web: http://irievibrations.tripod.com

Robin Chavez recalls performing with her dance class when she was 3.

“My aunt was an opera singer in Mexico City,” says Chavez, who sang in church and school choirs through childhood. “Our family sat around the table and listened to her sing.” It was this inspiration that led Chavez to study voice privately at 13.

Soon, Chavez embarked on musical theater and rediscovered her passion for opera, studying it in college.

After college, the soprano traveled monthly to New York to perform and study voice, a schedule she kept up for five years. The experience paid off: Chavez gave performances in Rome and Germany.

But in 1996, life hit a sour note.

Chavez was found to have dermatomyositis, an inflammatory muscle disease that affects fewer than 20,000 people in the nation.

During the one-year period of diagnosis and treatment, Chavez’s muscles, including those in her vocal cords, were affected. “After one song, I was hoarse. It was scary,” recalls Chavez, whose medication has since stabilized her condition.

Chavez was uncertain of her future but says the diagnosis forced her to “focus on what I loved to do.” The singer went on to perform four operas in two months at a summer festival.

In 1999, she sang on her community’s local MDA Telethon broadcast and appeared on the 2000 and 2001 national Telethons.

“Singing is a freedom, even if you’re not performing,” Chavez, now in her mid-30s, says. “You can be transfixed at a concert. When there, you’re not in a wheelchair. You’re part of a bigger thing.”

Chavez now sings a sacred concert series, a combination of classical, spiritual, and traditional hymns, all as fund-raisers for orphanages across the globe.

Chavez’s other love is being a mom to her 2½-year-old adopted son, Alejandro. During the long adoption process, Chavez recorded nursery rhymes on tape for the toddler. When her son arrived at his Texas home, she continued playing the tapes at night for consistency in his new environment. They had a calming effect on him.

A trip away from home proved hard on the toddler, however, when Chavez forgot to take the tapes.

“He was having nightmares at night.” When they returned home, she began playing the tapes again to great relief, a testament to music’s therapeutic value.

Robin Chavez on the Web: www.mda.org/publications/fa-myosi.html

Ken Glessner of Atlanta loves to sing. This active 68-year-old performs regularly at MDA holiday parties, assisted living centers and other venues.

Glessner, who has Becker muscular dystrophy, is a one-man show with 164 performances last year alone. He started singing old standards, as well as classic and traditional country in 1995, with the help of his karaoke machine.

“I just take a portable PA system with me when I perform,” Glessner says.

“I work with seniors and it does them a lot of good,” he says of music’s healing powers.

“Once, after a performance at an assisted living home, a woman got up out of her wheelchair and walked over to thank me,” Glessner says. “She told me it was the first time she’d walked in 6 months.”

He recalls singing at another assisted living center. One woman was a double leg amputee with only one arm. “In her condition,” beams Glessner, “she was still tapping her hand to the music. It’s very rewarding to make a difference.”

Since he knows singing for seniors is important, he’ll just keep on doing it right from his scooter. Especially if he can sing one of his favorites, Hank Williams’ “Hey, Good Lookin’.”

Mike Von of Austin, Texas, grew up on Jim Croce and John Denver. He began taking guitar lessons at 13, and after a year his teacher told him to create his own style. So he did.

“I realized that because of my spinal muscular atrophy, I couldn’t play fast leads,” Von says. Instead, he relied on rhythm guitar with musical accents and fills. It didn’t hurt that this baritone could carry a tune.

Von joined his high school and church choirs in 1975. In college, he sang and played electric guitar in bands. After moving to Austin, he eventually teamed up with his church choir and has been director since 1999. In 2003, Von took the next step.

“I wanted to record original material on CD while I could still play the guitar well,” says Von, 47. Using a friend’s home recording studio, Von produced and recorded “One Day,” a CD of soul-searching songs.

“It makes me happy that I can be a musician despite this condition,” notes Von, who teaches guitar lessons. In 2004, he joined a Christian rock band, Devin Garza and Messenger, to further enrich his musical journey.

“Music helps people’s moods, brings them a smile, and a tear perhaps,” says Von, who either plays his favorite CDs or plays the guitar to get his mind off his troubles.

Mike Von on the Web: http://cdbaby.com/cd/mikevon or http://devingarza.com

Joseph Gapko grew up on classical music. Born and raised in Eau Claire, Wis., by parents who were musicians, Gapko sang in school and church choirs.

Before he knew it, Gapko, who has Duchenne muscular dystrophy, was singing Italian arias in statewide competitions.

Now a senior majoring in economics and music at the University of Wisconsin in Eau Claire, Gapko, 22, still performs at state competitions, singing in French, German and Italian.

The tenor’s main struggle as a singer is breath support. “My lung capacity is 50 percent, but as you become a better singer, you improve at managing your breath,” he says. Nor does he let his cardiomyopathy interfere with his passion.

To date, Gapko has performed at numerous MDA-related events, summer camps and fund-raisers, and is recording a CD to benefit MDA.

Gapko knows his talents are a gift and says, “It doesn’t matter how limited you are. You can still be musical.” At an MDA conference he learned that kids in wheelchairs are having fun “DJing” with MP3s from their computers.

“In a world where many bad things are happening, it’s amazing that people turn to music,” Gapko says of music’s healing powers. “Music can put you in a different place than the one you occupy.”

Tristan Archer, 13, always knew that he wanted to play an instrument. Never mind his spinal muscular atrophy. He began with piano lessons in the third grade, but found his niche playing bass guitar.

Archer, of Austin, Texas, joined the Kealing Middle School jazz band. There, he met a group of friends who started a band, Guess.

“I haven’t seen many famous guys rocking out in a wheelchair,” Archer says. “It’s new to audiences.”

Archer performs by resting his bass on his leg and wheelchair. “I rely on others to move amps and get on stage,” he adds. Guess plays Jimi Hendrix, Creedence Clearwater Revival and originals, too. The band is now in contact with an agent specializing in promoting young bands.

Archer finds respite in playing and listening to music. “It can be peaceful,” he says. “When I’ve had a hard day physically, I like playing bass instead of video games.” It helps him forget about his problems.