Forget dumbbells — this 13-move ab workout builds a strong core in 15 minutes

GAINSBYBRAINS ab workout from YouTube
(Image credit: GAINSBYBRAINS/YouTube)

Rather than spending hours in the gym, why not give this quick six-pack ab workout a go? Forget fussy dumbbell changes or even having to stand up, this at-home ab workout blasts your entire core in 13 moves and 15 minutes, with no equipment necessary.  

The Train With GAINSBYBRAINS six-pack workout gets its name because it primarily works your rectus abdominis — the abdominal muscles located at the front of your stomach responsible for the chiseled six-pack look. Sure, they look good, but your core muscles are also responsible for good posture and movement and keeping you injury-free. 

That’s why this workout hits your entire midsection, including your upper abs, lower abs, and obliques, kicking up a fire in your core in the process. We recommend grabbing one of the best yoga mats to support your lower back and get ready to build seriously strong core muscles with a quick and effective at-home ab workout. 

If you’re new to exercise, our fitness editor tests running shoes for a living, and this is the pair she’d buy. Finding the perfect kit will keep you safe as you hit the ground running with your fitness goals during the new year. 

Watch Train With GAINSBYBRAINS 15-minute six-pack ab workout 

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The bodyweight ab workout is suitable for beginners and advanced gym-goers, so scale it to your strength level by making any modifications you need throughout. You’ll work for 45 seconds, followed by 15 seconds of rest between, for a total of 13 no-repeat exercises hammered out EMOM style (every minute on the minute). 

We strongly recommend following the video to check for tip-top form, but if you’re suffering from a lower back injury, consult a medical professional first, as exercises like crunches and leg raises could make matters worse. If crunches are your thing, I tried this 15-minute crunch abs workout — it’s no joke, and I use it to work on my upper ab engagement. 

Building strength and muscle in your core will help you reach sculpted and defined abs, but the journey isn’t simple for everyone. Factors like diet, sleep, hormones, and regular exercise like strength training all play a major role in achieving a sizzling six-pack. 

Woman performing a v-up during ab workout on a yoga mat arms and legs raised up

(Image credit: Getty images)

In fact, research by Nutrients found that adults sleeping less than seven hours per night were more likely to experience weight gain than those who slept optimally. If body recomposition or weight loss is your goal, we cover how to calculate your body fat percentage, and why it matters, and ways to safely boost your metabolism without dieting.

Aesthetics aside, if you want to build strength and muscle in your core, this ab workout is a perfect finisher for strength training and cardio workouts. Why not add it to this circuit dumbbell workout with 12 million views or one of our favorite shoulder workouts to work your entire upper body in one go?

You could even add one of the best adjustable dumbbells to increase difficulty, and practice regularly to build strength and feel more toned across your core over time. A hack I adopt when I have no weights is a technique called time-under-tension (TUT); it’s brilliant for bodyweight ab workouts as it helps me to control my movement simply by moving more slowly — it will also light a fire through the core muscles.

Want to give it a try? Slow as many exercises down as you can.


Next up: This Hyrox workout blitzes calories and builds full-body strength in three moves and sit-ups vs crunches which ab exercise is better

Sam Hopes
Senior Fitness Writer, Fitness and Mobility Coach

Sam Hopes is a level 3 qualified trainer, level 2 reiki practitioner and senior fitness writer at Tom's Guide. She is also currently undertaking her Yoga For Athletes training course. Sam has written for various fitness brands and websites over the years and has experience across brands at Future such as Live Science, Fit&Well, Coach, and T3.

Having worked with fitness studios like F45 and Virgin Active, Sam now primarily teaches outdoor bootcamps, bodyweight, calisthenics and kettlebells. She also coaches mobility and stretching-focused classes several times a week and believes that true strength comes from a holistic approach to training your body.

Sam has completed two mixed doubles Hyrox competitions in London and the Netherlands and finished her first doubles attempt in 1:11.

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