You do isometric ab exercises more often than you might realize, so these eight core-shaking examples ( all recommended by trainers!) will probably look pretty familiar. Isometric exercises [1] are moves that engage and challenge your working muscles without actually moving them; you contract or extend the muscle to get into the position and hold it there (sweating and panting). Or you move other muscles, like your legs in a hanging knee raise, while keeping your working muscles (your abs, in that case) strong and steady. That's a roundabout explanation to say that these kinds of moves are absolutely exhausting but also so effective.
Keep reading for the best isometric ab exercises, as recommended by trainers, that will have your core muscles quivering for as long as you can bear it.
Hollow Hold
The challenge of this tough static hold is to keep your lower back pressed against the ground the whole time, said Eric and Ryan Johnson, NSCA-certified trainers from Homage Fitness.
- Begin on your back with your legs straight and your arms extended overhead.
- Actively press your lower back into the floor and draw your belly button into your spine.
- Inhale to slowly lift your shoulders, arms, and legs off the floor. Keep your hands and heels as low to the ground as possible, while still pressing your lower back into the floor. Maintain tight abs and glutes. It's OK to bend your knees if straight legs are too challenging.
- Hold like this for five to 30 seconds to complete one rep.
Hanging L-Sit Hold
This move challenges your core as well as your hamstring flexibility and the strength of your hip flexors, Eric and Ryan told POPSUGAR.
- Jump up to a bar (or step onto a box if you need help reaching), and hang from the bar with both palms facing away from you.
- Use your abdominal muscles to raise both feet as high as you can, keeping your legs straight. Aim for parallel or higher, if you can.
- Hold this position for as long as you can, working up to 20 to 30 seconds.
- This counts as one rep.
Ab Wheel Rollout Hold From Knees
Instead of rolling right back to the starting position, hold in your extended position in this rollout, Eric and Ryan said. You'll feel the burn all through your core.
- On your knees, hold the ab wheel directly below your shoulders.
- Roll the ab wheel forward slowly, engaging your core as you do. Roll forward until your arms are fully outstretched and your back is flat.
- Hold for five to 30 seconds.
- Use your core to pull your arms back in, rolling slowly back to the starting position.
- This completes one rep.
Stir the Pot
Your arms are moving in this isometric exercise, but your core stays stable and still, making it a great isometric move. To make it even more difficult, Eric and Ryan recommended elevating your feet or using the ball to spell out your name!
- Begin in an elbow plank with your forearms resting on the top of a ball.
- Keeping your core strong and your body still, use your arms to roll the ball in a small clockwise circle. This completes one rep.
Pallof Press
"This movement is great to teach you how to resist rotation with your obliques and do so while continuing to breathe in your stomach," Eric and Ryan told POPSUGAR.
- Lower the carriage of a cable machine so it's about chest height, and attach a D-handle to the pulley. Adjust the weight so it's at 10 pounds. If this is too heavy or too light, feel free to change the weight.
- Standing with the left side of your body closest to the machine, grab the handle with both hands and take two or three steps out so there's tension on the cable. Hold your hands at your sternum, and make sure your body is square. If you feel like you're getting pulled to the left, this is an indicator that you should lighten the weight.
- On an exhale, press the cable straight out in front of your body. Be sure not to rotate toward the machine. Hold for two seconds before returning to the starting position. This counts as one rep.
Elbow Plank
We had to include the classic! "This is the movement from which most isometric core movements are built," said Tom Biggart, DPT, a physical therapist and athletic training and strength and conditioning coach at EBM Fitness Solutions [3]. "The key to succeeding at planks is a proper setup." If you have any discomfort in your lower back, he recommended dropping down to your knees [4].
- Start on the floor, resting on your forearms and knees.
- Step your feet out one at a time, coming into a plank position.
- Contract your abs to prevent your booty from sticking up or sinking. Your spine should be parallel to the floor, with your abs pulling toward the ceiling.
- Hold for 30 seconds, and work your way up to one minute as you get stronger.
Side Plank
"Oftentimes, simple is better," said Giancarlo Regni, ACSM, and Tyler Curtis, NSCA, of G-Strength [5]. The side plank, they said, is a simple effective isometric move that targets your obliques and helps to stabilize your lower back.
- Balance on your right hand and the outside edge of your right foot, with your body in one straight line. To modify, stagger your feet and bring your top leg forward.
- Hold for 30 seconds on each side to complete one rep.
Hollow Body Rock
The hollow body rock takes a hollow hold and makes it even more challenging. Personal trainer Kyra Williams [6], NASM, said hollow body rocks will "help you fire your midline and increase your core strength."
- Begin on your back with your legs straight and your arms extended overhead. Actively press your lower back into the floor and draw your belly button into your spine.
- Inhale to slowly lift your shoulders, arms, and legs off the floor. Keep your hands and heels as low to the ground as possible, while still pressing your lower back into the floor. Maintain tight abs and glutes.
- Use your core to propel yourself into a forward rock so your arms and chest are positioned higher than your legs and feet; then, rock back down, keeping your belly button pulled into your spine and your arms extended. You should be maintaining the hollow position through the entire rock.
- One complete back and forth motion equals one rep. Do three sets of 10 to 15 reps or two sets of hollow body rocks for 20 to 30 seconds.