Khloé Kardashian no longer works out as a punishment … but there was a point in time when she did. After always being compared to her sisters, Kardashian started believing the body shamers and the things she would read in the press ("I never thought I was fat until the media told me I was fat."), which ultimately resulted in a toxic relationship with her body. But after years of self-work and developing healthy habits, Kardashian finally turned fitness into a lifestyle and, oftentimes, a form of therapy.

The reality star and Good American founder tells InStyle that working out has become an indispensable part of her routine for both her physical and mental health. As you can imagine, the mother of two already has a jam-packed schedule, so she's always on the hunt for the most efficient workouts. Enter: Hydrow, aka the Peloton of rowing machines.

Kardashian laughs when she tells me how she stumbled upon the high-tech, subscription-based machine. She typically taps her mother, Kris Jenner, or big sister Kim Kardashian as workout buddies, and she discovered the rower in her mom's gym. "She thinks she's so cool that she turned me onto something," Kardashian jokes.

The old saying mother (momager) knows best rings true in this case because, with thousands of instructor-led courses filmed on open water around the world, the Hydrow has become a core part of Khloé's circuit training, though she describes it as a form of "escapism" rather than a dreaded task to complete.

"It's so tranquil and beautiful," she explains. "It's so relaxing, the sound of the water. Sometimes I just need an outlet to get away. I'm not a big runner, so for rowing, the sound of the water, it makes me feel like I can do it much longer because it's relaxing."

But it's not just all for fun — Kardashian says that rowing works about 86% of the muscles in your body." You get a big bang for your buck," she says. "It's just a kick-ass machine."

In the beginning days of her health journey — around the time she was filing for divorce from Lamar Odom — the star says she used to be "obsessive" over the number on the scale. "When I first started [working out], I cared so much. Maybe [it's] just being younger. I think you care about the scale," she shares. "The scale Fs with you. I don't even look at a scale anymore. I think it's really unhealthy. I haven't in years. They're just numbers."

These days, Kardashian is much more concerned with how she feels, and she adds that the mental release that comes along with working out is far more important to her than the "aesthetic." "I go off of how confident I feel in myself. I'm all about [doing] what's best for me, mind, body, soul. There is no one size fits all."

Read on for Khloé's fitness advice, the "mental release" she gets from working out, and which sister she has a friendly fitness competition with.

So your mom inspired you to get the Hydrow?

Some of the sisters or my mom sort of get mad if we're taking things from one another, but we get inspired. I see cool stuff, I'm like, "Oh, I want that too." It's so funny that we become territorial over things.

Does your mom love that she influenced you, or is she mad you copied her?

She loves it. She also just had a hip surgery, and the rower is so good on your joints. Her mobility is great, but she doesn't [want to have] hard impact on things. And I've had three knee surgeries, and I also just like to switch up my cardio. I just never thought about rowing until I saw it at her house. And then I was like, "Oh, this is genius. I need something new to switch it up."

Do you ever row with your mom or sister?

We don't row in the same place together because we don't have enough machines at one place because we work out together. If someone's at my house, for example, I'll be rowing while they're doing a weightlifting set. We are very competitive, especially Kim and I. We'll be like, "OK, I'm going to beat the meters you got." 

That's so nice to have a workout buddy!

It is. It makes it so much better. That's also why I like the rower because if you don't have a trainer, if you can't afford one, [or] just don't have access to one, I love that the rower has people there that are talking to you, and engaging with you. Sometimes I'm in the gym, and even though I've done this for so many years now, I just will do the same old stuff and your body gets used to it. So if I don't have a trainer here or a sister here to motivate me, then at least you have the person on the screen motivating you.

How does the Hydrow differ from other machines?

One thing that I love about the rower is everything is filmed outside in these real locations, which is so cool. 

I really don't like whales at all. It's a huge phobia of mine. A really weird phobia, I know. That's a full other interview. There sometimes will be whales [in the classes] — I will have a panic attack seeing it, but my daughter is enamored. She's like, "Mommy, there's a whale." I'm like, "Don't draw attention to it." 

What are some of the mental benefits you've seen with working out?

The reason why I turned to the gym was actually through my divorce. I didn't really know what to do. Of course, in the beginning you [have to] get over that hump of it being really hard and something so new for you. But I felt so accomplished. I'm sort of a control freak, but in life we can't control everything. But the gym, what I put in it, I know I'm going to get out of it. And being a control freak — I'm proud of it — I love that I have that control.

And then just the release. If I'm having a really bad day, I go to the gym. I might not want to go to the gym, but I go and right when I'm done, I feel so much lighter. I've never regretted going to a workout. I've always regretted missing them or pushing the snooze button. 

What is your advice for staying so disciplined and motivated?

I think you have to listen to your body for sure, but no one's going to push you. So you do have to listen to yourself and know when you're really tired versus making excuses. The beginning is the hardest — I think the first three weeks are the biggest challenge. And then, once you get over that, I do feel like everyone finds a rhythm. 

Start small — I started [by setting] really small goals for myself. I used to be like, "OK, tomorrow, I'm cutting out all sugars, carbs, and I'm working out five days a week," and it was such an unrealistic goal that I was setting myself up for failure. I did start like, "I'm going to start working out two days a week, and I'm not going to change my diet." But because [I'm] working out, it made me want to make smarter choices, drink more water, and eat a little better, so it becomes a natural progression. Then I would say, "Now it's three days a week," and I would slowly do those add-ons, and it became not so aggressive. And I would reward myself.

How have your fitness goals evolved over the years?

I think my fitness journey evolves by [having] new challenges. I was fit before I got pregnant, and then I got pregnant, and I was like, "OK, let me see if I can do this again." There's no one size fits all. There's no right or wrong way.