No sit-ups or crunches — just 15 minutes of core building kettlebell exercises

Woman holding a kettlebell in an upright row against orange background
(Image credit: Shutterstock)

I'm someone who finds standard ab workouts a little dry. Sit-up to crunch to plank, back to sit-ups, and so on. While these exercises are effective for engaging your core muscles, they’re far from your only options. If you also like a more versatile ab session, this 15-minute kettlebell workout might be just what you need.

Led by fitness trainer Lindsey Bomgren, this interval-based routine combines fat-burning cardio with core-strengthening moves to build muscle definition. Using one of the best kettlebells, Bomgren demonstrates each exercise, with an assistant trainer offering dumbbell variations for those who don’t have a kettlebell.

Bomgren uses two kettlebell sizes during the workout, but one is plenty if that’s what you have. Choose a weight that challenges you but allows for proper form to avoid injury.

Watch Lindsey Bomgren's 15-minute kettlebell core workout

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There are seven exercises to complete. For each, you’ll work for 40 seconds, rest for 20 seconds, and then repeat the circuit, switching sides as needed. While some people prefer no-repeat workouts, I find that having one set of repeats in a workout helps me fully feel the effect of each move on my core and allows me time to improve my form.

The kettlebell is an excellent tool for core workouts because it requires stability from your core, engaging all the muscles to maintain control throughout each exercise. Your core isn’t just your abs, it includes your lower back, obliques, and the muscles around your hips.

Working your entire core is important for overall strength and stability. My colleague Sam Hopes, a personal trainer, has explained the difference between ab and core muscles, as it can get a little confusing when people so often use the terms interchangeably.

Although it’s tempting to speed through the exercises, there’s no prize for finishing first. Each move should be performed for the full 40 seconds with proper form and this is what will help you get better results.

The demonstrations by Bomgren and her assistant Rachel are there to help you feel more confident with the exercises and stay injury-free.

Remember to keep your core engaged throughout each exercise, it makes a significant difference. If I zone out during a workout, I sometimes forget to engage my core, which I know affects my form and results.

Engaging your core doesn’t just mean sucking in your belly. Instead, think of pulling your belly button back toward your spine to create a stable midsection that supports your movements.

Yoga and Pilates are two excellent practices for developing core strength and gaining a deeper understanding of how to properly engage your core muscles. If you fancy giving either a go here are some Pilates exercises for strengthening your core or try these ab exercises you can do with a yoga block.

More from Tom's Guide

Jessica Downey
Senior Fitness Writer

Jessica has been a fitness writer at Tom’s Guide since 2023, bringing three years of experience writing about health, fitness, and the great outdoors. Her passion for exercise began during her childhood, where she spent weekends hiking and competing in local athletics club events. After earning a master’s degree in journalism from Cardiff University, Jessica found the perfect way to combine her love of storytelling and fitness into a career.

Jessica is passionate about testing fitness gear and tech, using her reviews to help readers make informed buying decisions. She ran her first marathon in April 2024, finishing it in 3 hours and 48 minutes. Through her training, she’s developed a deep understanding of what it takes to grow as a runner, from effective workouts and recovery techniques to selecting the right gear for every challenge.

When she’s not at her desk, Jessica enjoys spending time in the kitchen crafting new recipes, braving cold water swims and hiking.

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