Forget sit-ups — Sculpt strong abs with this simple core crusher workout

 a photo of a man doing a russian twist
a photo of a man doing a russian twist

If you’re looking for a quick ab workout to target all of the muscles in your midsection, look no further than our core crusher workout. Unlike other complicated ab workouts that require tons of equipment, you can put your best adjustable dumbbells and best kettlebells to one side for this one, as it only requires your body weight.

As a reminder, if you’re a complete beginner, you’re returning to exercise following an injury, or you’ve recently had a baby, it’s a good idea to check in with a doctor or a personal trainer before trying a new workout.

What is the workout?

The workout is pretty simple — you work for 45 seconds, followed by 15 seconds of rest for each of the four exercises. If you’re a complete beginner, shorten the working time to 30 seconds and rest for 30 seconds. If you’re looking to up the intensity, work for a full minute and skip the rest. Complete three to four rounds of the circuit, depending on how much time you have.

Side plank

To do a side plank lie straight out on one side, legs stacked. Rest your forearm flat on the floor and ensure your elbow is in line with your shoulder. Engage your abs and raise your hips and knees from the floor, keeping a straight line from head to feet. Only your forearm and foot should be in contact with the ground. Don’t allow your hips to sag and keep looking straight ahead for the duration. You can rest your top arm on your hip or, to make the move more challenging, raise it towards the ceiling. If you’re really looking to up the intensity, hold a dumbbell in your top arm.

If you do four rounds of this circuit, switch sides each round. If you do three rounds, switch sides after 20 seconds. Here’s more on how to do a side plank with perfect form.

Plank toe taps

Start in a high plank position, with your hands shoulder-width apart, your palms flat on the floor, and your feet hip-width apart. There should be a straight line from the crown of your head to your heels. Make sure you keep your back straight by thinking about sucking your belly button into your spine. Engage your core, and lift your hips while keeping the rest of your body still. Think about moving into a downward dog position. As your hips lift, lift your right hand off the floor and tap your left foot. Make sure your back is still straight as you do this. Moving slowly and with control, return to your high plank position. Repeat on the opposite side. That’s one rep.

Here’s more on how to do plank toe taps with perfect form.

Dead bugs

To do a dead bug, start by lying on your back with arms straight above you, and your knees in a tabletop position. Slowly lower your right arm to a couple of inches off the floor behind your head; as you do so, stretch your left leg away from your body and lower that to just above the floor. Pause, then return to your starting position and repeat on the opposite side.

Make sure you keep your lower back pressed into the mat for the entire exercise — to do this, think about sucking your belly button into your spine. Again, to up the intensity of a dead bug hold a dumbbell in each hand, or strap a set of the best ankle weights to your arms. Here’s how to do dead bugs, and the variations to try.

Russian twist

If you’re looking for a challenge, you can hold one of the best adjustable dumbbells in two hands for this exercise, as our resident personal trainer Sam is doing in the video. To do a Russian twist, sit on an exercise mat and engage your core as you lean backward, lifting your legs off the floor, so you are in a V-shape position.

You can cross your legs if it helps, and knot your hands together in front of your body. Bracing your core, twist your torso from side to side, and think about lowering your hands to the side of you as you twist. Follow your hands with your eye line. Continue to twist from side to side without dropping your legs to the floor.

What are the benefits?

The workout focuses on strengthening the midsection of the body, not just to sculpt strong muscles, but to allow you to stabilize and move better. Working on your core strength can reduce lower back pain, particularly important if you spend a lot of time sitting behind your desk working. Exercises like dead bugs target the deep inner core muscles and pelvic floor — these muscles work to protect and stabilize the back.

What’s more, despite only being 12 or 16 minutes long, you’ll need to keep your core engaged throughout the workout. By this, we mean thinking about sucking your belly button into your spine and moving from your midsection. The movement involved in a Russian twist, for example, forces you to really engage your core to stay sitting still, but it also works on your stability and targets the muscles in the lower back. These, in turn, can help with your posture.

Despite only consisting of four exercises, this workout also targets all of the muscle groups in the mid-section, including the six-pack muscles that run along the front of the body, the deep inner core muscles, and the internal and external obliques.

If building visible abs is your goal, you’ll need to work on hitting all of these muscles in your workouts. That said, visible abs are the result of a low body fat percentage, not endless planks. Your cardio levels, diet, hormones, stress, and sleep all affect your overall body fat percentage, so take a look at your overall health — here’s more on how to calculate your body fat percentage, and why it matters.

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