No sit-ups or crunches — this 15-minute dumbbell workout builds a stronger core and improves your posture

a photo of a woman with abs sat on an exercise mat holding dumbbells
(Image credit: Shutterstock)

We all know the standard ab workout involves moves like sit-ups, crunches, planks, and let's not forget Russian twists. While these moves are great for targeting your core, sticking to the same routine can get repetitive and, let’s be honest, a little boring.

That’s why it’s important to mix things up by trying new exercises and incorporating new equipment like a pair of the best adjustable dumbbells.

This four-move core-strengthening workout comes from Sandy Sklar, a fitness trainer who shares muscle-building workouts and tips with her million plus Instagram followers. Sklar places a big emphasis on strength training routines designed to be done with ease at home or the gym.

There’s minimal setup with her style of workout, so there’s no talking yourself out of it because it’s too much admin or takes too long. As Sklar says in her post, "Grab a dumbbell and let’s hit the floor."

Watch Sandy Sklar's 4-Move Core Workout

  • Bear plank push through x 16-20 total
  • High plank pull through x 16-20 total
  • Pull over crunch x 12-15
  • DB hollow hold with large flutter kicks x 20-30 total

The aim of the workout is to perform all four exercises in a circuit with minimal rest and repeat for three to five sets. Depending on how many sets you manage to complete and how little rest you take, it should only take between 10 and 15 minutes to do.

Sklar recommends minimal rest to keep your core muscles engaged for longer, which in turn helps to improve muscle endurance and strength. Little rest also raises your heart rate which helps burn more calories and makes the workout more time-efficient.

Of course, if you're struggling to get through the circuit, don't be afraid to extend your rest periods. As your core strength improves, you'll find it easier to complete the workout with shorter breaks.

What will adding dumbbells into your core workouts do?

You can get great results just using your body weight to train your core but, adding in some weight can introduce a greater challenge and keep things versatile.

Dumbbells force your core to work harder because they require greater stabilization during each movement. When holding a dumbbell while doing moves like the pull-over crunch or bear plank push-through, your body must recruit additional muscles to support the weight.

With added resistance, your muscles are forced to adapt, which can accelerate growth and definition. It also adds an extra challenge compared to bodyweight exercises alone, helping to break through any fitness plateaus you might experience with more traditional core exercises.

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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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