Read on for how my daily hollow holds went and my unexpected results after 21 days.

The Workout: Perform Hollow Holds Daily For Three Weeks

From the jump, I wanted to perfect my hollow hold. Luckily, I didn’t have to look far for tips and tricks. This core stabilizer is a go-to for Kara Liotta, CPT, co-founder of KKSWEAT. She previously gave Women’s Health a complete rundown of the move and all of its benefits. You don’t have to break a sweat to get the fitness benefits. Not only did my core become significantly stronger throughout the course of this challenge. Hollow holds help strengthen the muscles that prevent lower back pain and improved posture, according to Liotta. I’m down for that!

How to:

1. Start lying on back with with your arms extended overhead on floor and legs straight resting on mat.
2. At the same time, and with control, lift arms, head, shoulder blades, and legs off the floor. (You’ll look like a banana, according to Kara.)
3. Hold for 20 seconds then return to starting position. Rest for 10 seconds.

Pro tip: Don’t arch you back. Keep it sealed down to the mat even if that means holding your legs and arms higher until your core is stronger. A stable back is key to doing this move correctly.

Week One: I started slowly after a fitness hiatus to nail proper form.

I was basically starting from ground zero at the beginning of this challenge. I had been traveling a lot for work the past few weeks, and my fitness routine was all but nonexistent. I did a ton of walking to stay active, but I had barely been doing any strength training.

I felt like the hollow holds were a great little workout to revive my fitness routine and nothing too intimidating. I assumed knocking out daily hollow holds wouldn’t be as challenging as planks. Abs exercises are also a regular part of my routine, so I was confident my core could handle them. My only small concern was my neck, which sometimes feels strained in the hollow hold position.

Protect the neck: Bend the knees slightly and/or raise the legs higher, and keep the head and neck on the floor and focus on the leg lift and hold first to help avoid straining the neck or low back.

I started off the challenge repeating four sets of hollow holds every day whenever I could find the time to fit them in. This typically ended up being in the evening after I finished up my work for the day. When I did manage to have a proper sweat sesh during the day, I would tack the hollow holds onto the end of the workout.

I progressed quickly. By day six, I upped it to five sets of hollow holds a day.

Week Two: I stayed consistent and leveled up with variations.

Week two didn’t really bring any new challenges for me. Remaining consistent was key, and it was easy to do that with this speedy workout challenge. I could sneak it into my daily life without sacrificing other activities or needing a ton of time.

The hollow holds definitely got easier to complete. Since it wasn’t mega-challenging to begin with, it wasn’t as easy to see progress. During week two, I also began experimenting with some hollow hold variations. I added a flutter kick in for 10 seconds in some of the sets. I didn’t track these consistently, but added them in when I felt like my abs could use the extra burn.

Week Three: I could hold my hollow hold longer and upped the challenge to flutter kicks.

Usually the three-week mark is around the time I start to get a little bored with a challenge. Thankfully, the rest of me was as engaged as my abs with this one. I think the quick nature of hollow holds (and the fact that I get to lie down to complete them) meant that I didn’t even have the time to get bored.

During week three, I also incorporated more flutter kicks into my holds. Adding the variation meant I could really feel my core. There was definitely a lot of shaking going on.

What Doing Daily Hollow Holds Taught Me

Overall, I love this challenge. Hollow holds work a number of muscles in the core and back, but it felt easier than holding a plank. I didn’t have to hold my entire body up with my shoulders and arms. Plus, I didn’t break a sweat while rocking my hollow holds (unless I paired them with my entire workout routine). This was awesome because I could squeeze them in even if I needed to run out the door 5 minutes later. They get my vote as the easiest exercise to incorporate into daily life without disrupting it.

1. Short intervals made this challenge manageable.

I went into this challenge expecting to get bored at some point, but the quick 20-second intervals really helped keep me focused. I wasn’t struggling as much to get through the workout as I was with planks, I didn’t need to turn on a show as a distraction.

What’s more, I never dreaded an upcoming workout. And best of all, I could complete this exercise anywhere and any time. I didn’t sweat so I didn’t need to shower immediately afterwards. That convenience couldn’t be beat.

2. I felt the burn in my whole core.

Having a brief recovery period of only 10 seconds between sets meant that my abs were always fired up. In fact, I actually found myself really embracing this challenge because it was a different type of core exercise than I typically do. I could feel these hollow holds targeting the entire core, my back muscles included.

And, it’s exactly what my abs needed. While I try to incorporate a variety of core exercises (dead bugs, bicycle crunches, Russian twists, and similar core exercises) into my regular routine, I know don’t do static holds enough. The hollow holds upped the time under tension for my muscles, which makes them so effective.

3. Modifying the move helped me ease back into a fitness routine.

Coming into this challenge without being in a consistent routine made me feel like I was starting from scratch. An involved or super difficult challenge probably wouldn’t have gone well. But, this quick workout option and easy modifications with hollow holds gave me some grace to ease back in to the swing of things.

I needed some additional support to do the move properly in week one, but it didn’t take long until I was working on variations and increasing the difficulty without any modifications.

Plus, it gave me mini milestones to work toward. First, I had my hands behind my head, then I could hold them out, and next I was able to incorporate scissor kicks. I knew I was progressing week after week. I felt more confident and added more full workouts into my days.

4. Listening to my body was key to success.

Being the competitive person I am, I want to jump into any challenge with gusto (and flutter kicks). However, this challenge taught me to tune into my body and learn what it really needs. If that means modifying something at first, that’s what I should do.

Often, I can feel my neck straining while doing certain exercises, so I knew I needed extra neck support on my hollow holds. As I progressed, I would just touch my fingertips to the back of my head to get my head positioning comfortable and pain-free. Once I could do that, I tried lengthening my arms out and maintaining my head position without creating strain. It eventually worked and I was able to progress comfortably.

Bottom line: This is one challenge I would definitely recommend if you’re looking to strengthen your entire core, and I certainly plan on keeping hollow holds in my revived fitness routine.