The one where Jennifer Aniston's fitness routine kicked my ass.

There's a reason the Friends alum has maintained an incredible figure over the years: Her workouts are hard AF.

And I know this first-hand because I tried a variety of the exercises Jennifer does for Pvolve, an online fitness brand she recently partnered with that offers a wide range of low-impact, high-resistance workouts.

But before I dive into the sweaty details of the superstar's routine, it's important to offer insight into her training sessions.

"I leave every workout feeling energized and strong, but not beat up," Jennifer told CR Fashion Book in an interview published Sept. 27. "Whatever your fitness level, it's a workout where you can truly start where you are."

Now, The Morning Show actress isn't lying when she says there's an exercise for everyone, regardless if you're a beginner or longtime devotee. However, when it comes to her preferred exercises—a section titled Jen's Picks on the Pvolve site—they aren't for the faint of heart.

Most of the exercises listed in Jennifer's section are full body workouts that focus on sculpting and strengthening, which was exciting for me since I've been on a kick (no pun intended) to tone up and build muscle.

There are also a handful of sessions that target specific areas, like the core and upper body. Moreover, and quite possibly a potential downside for some, many of the trainings require equipment, including a mat, gliders, a small exercise ball and resistance bands.

The three sessions I really gravitated towards were the Lower Body and Core Strength (20 mins), the Full Body Sculpt and Burn (20 mins), and the Lower Body and Core Sculpt and Burn (30 mins).

Although I like to think I'm an intermediate fitness level since I exercise regularly, these routines really humbled me.

For one, the Lower Body and Core Strength training made my legs shake throughout, as it focused on building strength in the glutes and inner thighs. By the time the planks rolled around, I was so ready to quit but pushed through.

After all, what would Jennifer do? Probably finish the work out she picked. And while I didn't feel beat up, as the Murder Mystery actress had promised, I certainly felt sore afterward.

Next, I tried the Full Body Sculpt and Burn, a session that targeted the hips, upper body and core strength with weight-training exercises. Foolishly, I thought this would be easy since it required light weights, but it definitely made me break a sweat and got my heart pumping. In fact, the trainer herself huffs and puffs throughout the video, proving it was no easy feat. 

But out of all the workouts I tried, my favorite was the Lower Body and Core Sculpt and Burn. I loved that it was a low-impact training, which doesn't make it any less challenging but a lot more doable. Additionally, I enjoyed that this training didn't really require equipment—just gliders—but you can easily do the exercises without them.

In short, Jennifer's workouts will make you work for the results.  

Now, let's just say Jen's Picks aren't for you. Maybe they're too intense or maybe you want something less involved, Pvolve also offers a wide range of trainings to choose from. 

Plus, they have sections that are specific to certain life milestones. They have a five-week menopause program, as well as a three-week post-natal series. Some workouts are even meant to help your body recover from pain or injuries, such as their physical therapy-inspired classes, which the brand says it co-creates with clinicians. 

Like Jennifer noted, there's truly something for everyone.

"I've been motivated to work out in a way I haven't been in years," she shared with CR Fashion Book. "I look forward to the challenging classes and I feel stronger and more comfortable in my body when I'm doing it."

Considering I pushed my body in ways I wouldn't have before, I can attest that Jen's picks are hard but very much worth their weight.

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