Forget sit-ups — these bodyweight ab exercises will define your core

a photo of a woman doing a side crunch
(Image credit: Getty/Javier Sanz)

Tired of the same old, monotonous ab exercises? You aren’t alone. Thankfully, there are ways to spice up your core workouts while keeping on top of your fitness goals.

Fitness coach and Sweat app co-founder Kayla Itsines has devised an invigorating ab routine that incorporates fresh moves into your workouts, challenging your core muscles in new and engaging ways. By incorporating unique variations and stimulating combinations, this workout not only adds excitement but also ramps up the intensity.

Before you get stuck into Itsines’ routine, remember that getting visible abs forms one part of core training, and there are various other reasons to strengthen these muscles; a strong core improves posture, helps you lift heavier weights and supports your torso and spine during movement. If building visible abs is your goal, you'll need to focus on your overall body fat percentage — here's how to calculate your body fat percentage, and why it matters

6 exercises to strengthen and define your abs

The workout combines six challenging exercises that will leave your core burning and abs sore the following day. You will complete 12 repetitions of each exercise and 24 (12 on each side) for the final exercise, which is the side plank and crunch. If you can, Itsines recommends completing the full circuit three times overall.

The routine includes ab bikes, leg raises, mountain climbers, side-to-side half burpees, inchworm, and side plank and crunch. All exercises are worth completing but below we dive into why the final three moves are particularly effective when training the abdominal and core muscles.

Side-to-side half burpee

To perform a side-to-side half burpee, start in a standing position and lower into a squat. Place your hands on the floor, kick your legs back into a plank, then jump both feet towards one side and back to the center. Repeat the jump to the opposite side. This exercise engages the abs, arms, and legs, making it a dynamic and effective move for a full-body workout.


To do an inchworm, begin in a standing position with feet hip-width apart. Bend forward at the waist, placing your hands on the floor. Walk your hands forward until you reach a plank position. Pause briefly, then walk your hands back towards your feet, returning to the starting position. The inchworm exercise targets the core, shoulders, and hamstrings while promoting flexibility and stability throughout the body.

Side plank and crunch

To perform a side plank and crunch, start in a side plank position with your forearm on the ground and your body in a straight line. Engage your core and lift your top leg toward your chest while simultaneously crunching your elbow toward your knee. Return to the starting position and repeat on the other side. This exercise targets the obliques and abdominal muscles, helping to improve core strength, stability, and overall abdominal definition.

What are the benefits? 

Regularly performing ab routines can bring numerous benefits to both aesthetics and physical fitness. Exercises, like the ones performed in Itsines’ routine, can help sculpt and define the abdominal muscles, creating a more toned appearance. Beyond aesthetics, a strong core provides stability and support for the entire body, improving posture, balance, and overall functional fitness. 

However, it's important to remember that a well-rounded workout routine should incorporate exercises targeting all muscle groups, including cardiovascular and flexibility training. By maintaining a balanced approach, you can optimize your overall health, strength, and well-being while reaping the rewards of a strong and toned midsection.

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Jessica Downey
Fitness Writer

Jessica is an experienced fitness writer with a passion for running. Her love for keeping fit and fueling her body with healthy and enjoyable food quite naturally led her to write about all things fitness and health-related. If she isn’t out testing the latest fitness products such as the latest running shoe or yoga mat for reviewing then she can be found writing news and features on the best ways to build strength, active aging, female health, and anything in between. Before then she had a small stint writing in local news, has also written for Runners World UK (print and digital), and gained experience with global content marketing agency, Cedar Communications.

Born and raised in Scotland, Jessica is a massive fan of exercising and keeping active outdoors. When at home she can be found running by the sea, swimming in it, or up a mountain. This continued as she studied and trained to become a PPA-accredited magazine journalist in Wales. And since working and living in London, she splits her time between weight training in the gym, trying new fitness classes, and finding scenic running routes. Jessica enjoys documenting this on her fitness-inspired Instagram page @jessrunshere where she loves engaging with like-minded fitness junkies.

She is a big fan of healthy cooking and loves learning more about this area with expert nutritionists she has met over the years. Jessica is a big advocate for building healthy relationships with food rather than building restrictive attitudes towards it. When she isn’t eating or running she also enjoys practicing yoga in her free time as it helps her to unwind and benefits her performance in other sports.