With or without celebrities who promote their workouts, some personal trainers make it big, creating big brands that go beyond the celebrity association. Check out some of the most recognizable names in the business.

Here are the most famous celebrity trainers, from former boxers to dancers who knew how to make the best out of their training and determination in order to help both Hollywood A-listers and regular people get in the best shape possible.

Tracey Mallett

Creator of The Booty Barre, a very successful group workout, English-born Tracey Mallett currently lives in Pasadena, Los Angeles, and is both certified personal trainer and a group fitness instructor. 

Tracey Mallett Celebrity Trainer

Her celebrity credits include Zooey Deschnael and Madonna, but her biggest claim to fame consists of creating a fitness program for Michelle Obama’s “Let’s Move” campaign, and she’s also the author of two best-selling fitness books: “Sexy in 6” and “Super-Fit Mama”.

Michael George

Michael George Celebrity Trainer

Definitely one of the most famous celebrity trainers, Michael George has worked with a lot of big names in Hollywood, including Julianne Moore and Reese Witherspoon. “Integrated Motivational Fitness” is his most recognizable program, but he also wrote a book (“Body Express Makeover”), created an iPhone app (Inteli Trainer) and an Xbox 360 game (Your Shape Evolved).

Gunnar Peterson

Gunnar Peterson Celebrity Trainer

Known as both the developer of the “Core Secrets” workout and as a personal trainer to celebrities including Jennifer Lopez, Sylvester Stallone, Angelina Jolie, and Kim Kardashian, Gunnar Peterson is one of the most recognized names in fitness. He’s on the advisory board of Fitness magazine, and has served written for Glamour, Muscle and Fitness, and Clean Eating magazine.

More: Best Celebrity Workout Videos

Mary Helen Bowers

Mary Helen Bowers Celebrity Trainer

A former professional ballerina, Mary Helen Bowers is definitely one of the most famous celebrity trainers. The New York based author of “Ballet Beautiful: Transform Your Body and Gain the Strength, Grace, and Focus of a Ballet Dancer” has an impressive list of Hollywood clients, including Natalie Portman and Liv Tyler, but she’s even more popular with top models like Miranda Kerr and Doutzen Kroes.

Harley Pasternak

Harley Pasternak Celebrity Trainer

The Canadian-born personal trainer wrote two hit books, “The Body Reset Diet” and “The 5-Factor Diet”, and celebrity clients include Lady Gaga, Orlando Bloom, Miley Cyrus, Kate Upton, and Halle Berry. His most recent claim to fame is a cameo in “Teenage Mutant Ninja Turtles”, where he’s doing a fitness routine with Megan Fox’s character.

Mark Jenkins

Mark Jenkins Celebrity Trainer

Author of “The Jump Off: 60 Days to a Hip Hop Hard Body”, Mark Jenkins is also among the most famous celebrity trainers, and has worked with Beyoncé, Sean “Diddy” Combs, Mary J. Blige, Tyler Perry, and many more. He’s also the founder of “International Fitness”, which focuses on training performance artists, and of the nonprofit organization “Musle and Music for Youth”.

David Buer

David Buer Celebrity Trainer

Atlanta-based personal trainer David Buer is well known for “Transform YOU”, a 12 week fitness program endorsed by Dr. Oz, and some of his celebrity clients are Leonardo DiCaprio and L.L. Cool J. He’s also worked with athletes including Joan Guzman, Cedric Boswell, and Rick “The Jet” Roufus.

Tracy Anderson

Tracy Anderson Celebrity Trainer

Developer of the “Tracy Anderson Method”, the fitness guru has worked with Madonna, Courtney Cox, Gwyneth Paltrow, and Shakira. With gyms opened on both coasts and in London, Anderson is not just most famous celebrity trainers, she’s also of the highest earners in the field.

Michael Olajide, Jr.

Michael Olajide  Jr Celebrity Trainer

With a client list that includes the likes of Hugh Jackman and 50 Cent, along supermodel Adriana Lima, and actresses Liv Tyler and Eva Mendes, Michael Olajide, Jr. is a former middleweight boxing champion turned celebrity trainer, and has a big New York following.

Denise Austin

Denise Austin Celebrity Trainer

Definitely one of the most famous celebrity trainers, thanks to her position as a member of the President’s Council on Physical Fitness and Sports under George W. Bush. She also had her own show on ESPN2, “Getting Fit with Denise Austin”, and continues to release successful workout videos and books.