This ‘abs on fire’ workout torches your core in 4 exercises

a photo of a man doing crunches
(Image credit: Shutterstock)

We don’t need to remind you that it takes a lot more than endless sit-ups to sculpt strong, visible abs — if this is your goal, you’ll need to focus on your diet, your overall body fat percentage, and your cardio levels. That said, strong abs are far more than just aesthetics — they can help you run faster, lift heavier weights, sit with a better posture, and protect your lower back from injury. If you’re looking for an ab workout to add to your next strength session as a finisher or use as active recovery on a rest day, we’ve found exactly what you’re looking for. 

The circuit, created by coach and personal trainer Courtney Fisher, is an intermediate workout, designed to work the muscles in your mid-section using just four exercises, and one of the best adjustable dumbbells. When it comes to selecting the right weight for your workouts, remember that it should feel challenging, but at no time should you have to compromise your form to complete the exercise. 

As a reminder, if you’re new to exercise, or you’re returning to exercise following an injury or a pregnancy, this might not be the best workout for you. It’s always a good idea to check your form with a personal trainer before adding weight, or reps.

What is the workout? 

In the description of her workout, Fisher writes, “Warning! Your abs will be on fire after this!” The circuit consists of four different exercises. You’ll complete three rounds of the circuit, with a one-minute rest in between. All you’ll need is one of the best yoga mats and a weight of some sort. 

Dumbbell weighted v-up — 10 reps

For this exercise, start by lying on your back, with your lower back pressed into the floor and your legs extended out away from your body. Hold a dumbbell in both arms and lower it behind your head, with straight arms extended out away from you. Engage your core, and lift your legs up towards the ceiling. At the same time, lift the dumbbell, and crunch your arms towards your legs (it does not matter if they don’t actually touch), before slowly, and with control, lowering your arms and legs back to your starting position. Don’t let your arms and legs fully rest back onto the floor, keep them hovering a few inches off the ground before moving into your next rep.

Dumbbell hollow lifts — 10 reps

For this exercise, start in the same position as the weighted v-up. From here, lift both legs a few inches off the ground and hold them here — your legs don’t move in this exercise. Make sure your lower back stays pressed into the exercise mat as you engage your core, and holding the dumbbell with both hands, you lift your arms up towards the ceiling and crunch your head, neck, and shoulders off the mat. Lower back down to your starting position, without letting your arms or legs touch back to the ground. 

Lemon squeezers — 15 reps

You don’t need a dumbbell for this exercise. Instead, start by sitting on your seat bones on your exercise mat, with your hands behind your glutes, and your fingers facing your toes. Stretch your legs out away from your body, and lean your torso back, until you feel your abs engage so that you are in a V-sit position. From here, engage your core and lift your torso up, at the same time bending both legs and crunching your knees in towards your chest. Then, extend back out to your starting position. 

Oblique lemon squeezers — 10 reps on each side

For this exercise, you’ll perform the same exercise as above, but with your legs twisted slightly, so you can feel your obliques working harder. Still keeping both hips on the mat, twist your legs into one side of the body as you crunch in, then swap to the opposite side as your crunch out. 

What are the benefits?

As mentioned above, there are a number of benefits to working on your core strength and adding weight to your ab workouts. If you’re looking to increase muscle mass in your midsection, studies show that weight training is one of the best ways to do so. Dumbbells increase the intensity and challenge, helping you build muscle, strength, and power across your torso.

Your core muscles run down the front and back of your body, wrap around your torso and extend down your waist, including your glutes and hip flexor muscles. Your diaphragm is technically part of your core network too, helping you breathe properly as you move. 

Weak core muscles make you more susceptible to injury and a limited range of motion. You’ll also find posture, speed, and weightlifting ability all affected. Keep these muscles strong and your body stable by training your core several times weekly. That doesn’t just mean dedicated ab workouts and can include compound exercises like squats or deadlifts as well.  

More from Tom's Guide

Jane McGuire
Fitness editor

Jane McGuire is Tom's Guide's Fitness editor, which means she looks after everything fitness related - from running gear to yoga mats. An avid runner, Jane has tested and reviewed fitness products for the past five years, so knows what to look for when finding a good running watch or a pair of shorts with pockets big enough for your smartphone. When she's not pounding the pavements, you'll find Jane striding round the Surrey Hills, taking far too many photos of her puppy. 

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