I've probably written the phrase "celebrity trainer" hundreds of times. It's a phrase that tells you exactly why we're supposed to care about this particular trainer's advice. After all, a trainer who's worked with Madonna or Courtney Love is just so much more exciting than a trainer who works with your cubiclemate. But what does it really mean to be labelled a celebrity trainer? What were these fitness pros doing before they had their first celebrity clients? Are the perks really as good as I imagine?

I spoke with some of the most recognizable names in fitness to learn more about what it's like being a trainer to the stars. Turns out, many celebrity trainers have mixed feelings about the title. Being called a "celebrity trainer" does earn them more clients and, as Gunnar Peterson pointed out, the opportunity to have a writer like me come calling. But these trainers don't want their work reduced to whether or not their clients happen to land on magazine covers.

Each trainer I spoke with assured me that while working with A-listers comes with a few special requirements (like being uber-flexible with scheduling), celebs aren't really all that different from you and me in the gym. Any paying client who's ready to work will get the same treatment as Jenna Dewan or Carrie Underwood. At the end of the day, we all sweat the same way—whether in our in-home private Pilates studio or at our local gym.

Here, five trainers share how they got their first celebrity clients and what it's really like to train famous actors and musicians.

Interviews have been edited and condensed for clarity.

1. Jennifer Johnson

Clients include: Jenna Dewan, Jessica Alba

SELF: Who was your first celebrity client?
Johnson: Jenna Dewan. I had been a trainer for a couple of years when we started together, and working with Dewan. When people see an in-shape celebrity, someone who clearly has fitness as a priority, it's a great representation of the trainer.

Does it help you book more clients?
For sure. It makes me more visible, and people appreciate it even more because the client is someone they aspire to be like. It's like, "Ooh, if Jenna's doing it, then I want to do it, I want to try."

How is training a celebrity different from training a "normal" person?
The biggest difference is scheduling. With celebrity clients, we often have to change the schedule a million times because they're on set for long hours, or have to fly out of the country. Jenna [Dewan] likes to come in and hit it and quit it in 45 minutes, because she doesn't have a lot of time. We go hard quicker.

But all my clients get celebrity treatment. I incorporate what workouts work best for each person—it totally depends on how the client connects best with their body and what gives them the best results. I started as a professional dancer, so that was important for me to bring to fitness. That's what makes me happy, and I feel like workouts have to be fun in order to be consistent. That's really key. My workouts are all part dance cardio and part muscle work, from light 3-pound weights and barre work, all the way up to to take my clients to the gym for heavy weight training.

What does the phrase "celebrity trainer" mean to you?
At one point, I would cringe when I saw it. I don't like it when people have trained a celebrity once and then get to call themselves a celebrity trainer. I feel like it can be overused. And just because a trainer may have trained a celebrity, they're not necessarily better. On the other hand, it's a phrase that I have to use, because if I don't, then it seems as if I'm not of that caliber. I'm almost forced to use it. I used to wonder, "Do I put that on my business cards?" The answer is yes.

2. Gunnar Peterson

Clients include: Khloe Kardashian, Jennifer Lopez, Sofia Vergara. Peterson is also the director of the strength and endurance of training for the LA Lakers.

SELF: How did you end up training so many celebrities?
Peterson: I started with Kelly McGillis in the early 90's when I had only been a trainer for two years. It's a misconception that a celebrity clientele always builds on itself—in my experience, it’s not often one celebrity comes from another. Where celebrities come from is completely random. Typically, it's from a trusted source, like their manager, an agent, a pediatrician. Someone who they’ve already entrusted with this component of their life.

How is training a celebrity different?
I like clients who like to work, and celebrities like to work. They have a goal every day. Celebrities [usually] have very specific goals, whether it's for aesthetics or performance, and you can't be judgmental of that. Regardless of what workouts we do, I train everyone [like an athlete]. For example, if it's someone with a music video coming up, we focus on cardio endurance, and ankle and knee stability.

What does the phrase "celebrity trainer" mean to you?
You train somebody who's famous. If you train the guy who owns all the car dealerships in a small town, then you might be the celebrity trainer of that town. There are some people who train celebrities who are not seasoned, and other trainers who don't train celebrities and are phenomenal. But I do get the opportunity to talk to you. I got to design my own gym, and the gym at the Dream Hollywood. What being a celebrity trainer gives you that's important is a platform. I try to be respectful of that.

3. Sarah Perla Hagaman

Clients include: Cindy Crawford, Kelly and Sharon Osbourne

SELF: How did you book your first celebrity client?
Perla Hagaman: I had been a trainer for two or three years working exclusively with Power Plate, a piece of equipment that uses vibration technology. Cindy Crawford purchased one, and didn't know what to do with it. She called Power Plate and they sent my husband and me over. From there, our relationship evolved into regular training. We've been working together since 2008.

Did that opportunity shape how you train and who you've trained?
Definitely. I created my company Blue Clay Fitness in 2006 to enter the niche of high-end training. We are solely responsible for the provision of high-quality services, with confidentiality and availability and concierge services with our training. The process of getting new clients is very much the word-of-mouth, especially in that tight-knit community.

How is training a celebrity different from training a "normal" person?
Trust is a huge component of having longevity, especially with a celebrity client. I've never taken and posted a picture that Cindy didn't take. That trust is a huge, huge part of it. There are also perks: I trained Kelly and Sharon Osbourne for a long time, and got to travel with them to England. But I think part of being a successful celebrity trainer is not putting anybody on a pedestal. Exercise is very humbling. There's no makeup, it's just the real deal.

Scheduling is the biggest nightmare. It's like being a restaurant manager and scheduling your staff. Some clients are early risers, some prefer to work out in the afternoon. I try to appease everybody, and also geographically make it work for myself as I'm driving around Los Angeles. In any given day, I'm in Beverly Hills, Brentwood, Calabasas, and Malibu. Celebrities also go on tour, or schedules change, and you can't take it personally.

What does the phrase "celebrity trainer" mean to you?
I don't give it that much thought. I'm a mother of two kids, I've got my own life, so I go in for my hour and I go out. [I spend] one hour [with a specific client], and there are 23 other hours in the day.

4. Erin Oprea

Clients include: Carrie Underwood, Martina McBride, Jana Kramer, Kelsea Ballerini, Aubrie Sellers

SELF: Who was your first celebrity client?
Oprea: I started working with Lee Ann Womack in 2006. I've been with Carrie Underwood since 2008. I also work with Martina McBride , Jana Kramer, Kelsea Ballerini-there are a bunch.

Did these relationships build on each other?
Yes. Either their teams talk with other teams or the [celebrities themselves] talk amongst each other. I don't know exactly how it goes down behind the scenes, but it's word of mouth in the industry.

How is training a celebrity different from training a "normal" person?
The biggest difference is that celebrities are in and out so much. So they do a lot of FaceTime sessions, too. I think FaceTime is just as much fun, I don't see any difference in people's motivation. Everyone has off days, but the majority of FaceTime sessions are no different [than being together in a gym].

What does the phrase "celebrity trainer" mean to you?
It was horribly awkward for me the first several years. I thought, I'm not a celebrity trainer, I just work with a lot of fun people. Now, I don't think about it.

5. Nicole Stuart

Clients include: Kate Hudson, Goldie Hawn, Courtney Love

SELF: Who was your first celebrity client?
Stuart: Courtney Love in 1997. I had only been a trainer for a year or two when I first met her. I was working for Mari Winsor [who is widely credited for popularizing Pilates] in a little tiny Los Angeles studio. (I'll never forget, when I went for my job interview with Mari she said, "I'm training Madonna at 12. Come in at 1." We had a really good workout together, and she asked me to start the next day. I started off answering phones, then eventually supervised group classes.) Mari had trained Courtney a bit, and she heard that she needed a trainer with her on the road. I really didn't know much about Courtney Love, but I heard that phone call, and thought it would be a pretty cool job. I met her, she liked me, and that was it. With the money I made, I was finally able to get out of debt.

Did your business grow from there?
Based on word of mouth, the next person I got after Courtney was Kate Hudson. She was up in Canada and went to see Courtney perform; Courtney ended up mentioning my name. Then later, [Hudson] asked a friend for a Pilates trainer recommendation. The friend wrote down my number, and that was the second time [Hudson] had heard my name. She called just as she was starting Almost Famous. I took her to a gym and we got along really well. I started training her regularly, and she referred me to her mom, [Goldie Hawn].

I never set out to be a celebrity trainer. I thought of myself as I was trying to make it in acting. But after four or five years working at the Pilates studio, I [had enough clients to go] out on my own.

How is training a celebrity different from training a "normal" person?
[What we do] depends more on your strength than on who you are. I train classical Pilates, so the basic exercises don't change. But after doing it for so many years I've started to incorporate different modalities like yoga, circuit training, and TRX, into it.

What does the phrase "celebrity trainer" mean to you?
I don't have my own definition, but I know that I'm a trainer and I'm trying to do a really good job, and I'm still learning in my craft.