On the surface, the TRX Suspension Trainer looks pretty unassuming. But these two adjustable straps may just be the best piece of equipment to strengthen your abs and core. “When we work our core on the TRX, it’s really challenging” says Shannon Colavecchio, who is an AFAA and ACE-certified personal trainer and certified in TRX Suspension Training and TRX RIP Trainer.

“With your hands or feet in the TRX, you only have two points of contact with the floor to help you stabilize your body, which means you have to recruit your core muscles,” says Colavecchio. Constant instability means those abdominal muscles are always on.

“What I really love about the TRX is that it engages so many muscles beyond just the specific one you’re working,” says Colavecchio. “It’s an efficient tool. You spend less time training, but you get more value from that training time,” she says. The owner of Badass Fitness Studio in Tallahassee, Florida also notes that TRX is accessible to people of all fitness levels. “I can have a class of 20 people ranging from pro football players to older women,” she says. “We can all work at our own level and progress, at our own pace. You can make the TRX work with you by making the exercise easier or harder — it’s all about changing the angle of your body.”

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The 7 Best TRX Exercises to Work Your Abs

Tone up that six-pack to help improve core and back strength, as well as posture. Remember, form is key, especially on the TRX. “Just about every move requires that you be in a perfect plank position,” says Colavecchio. “You want a straight line from the neck all the way to the heels. Activate your glues, quads and hamstrings. If you are aware of this muscle engagement on the TRX, you’ll get so much more out of your workout.”

Colavecchio also recommends looking for modifications that will allow you to perform each move correctly and safely. “It takes some of the intensity away, but it allows you to perfect a move properly,” she says.

Activate those abs! Perform each of the seven exercises below in order with control. For those who are new to TRX, complete two rounds of 10 reps of each exercise. For those who are familiar with TRX training, complete two to three rounds of 15-20 reps of each exercise.

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1. TRX Pikes

TRX pikes help you build a strong core by challenging your balance and stability, along with your abdominal muscles. “You can adjust the intensity of the exercise by how big your pike is,” advises Colavecchio. Plus, this is a great exercise to build strength for more advanced exercises such as handstands.

How to: Adjust the TRX straps to mid-calf length. Begin in a suspended plank position with your feet in the TRX loops, toes facing down and wrists directly underneath your shoulders. Your body should be in a straight line from head to toe (a). Pressing down through your palms, lift your hips up towards the ceiling by drawing your legs towards your chest until you look like an upside-down V, or as high as you can go (b). Slowly lower your legs and return to the starting position (c). Repeat.

2. TRX Atomic Push-Ups

They don’t call these atomic push-ups for nothing. It’s essentially a push-up followed by a crunch. This exercise is not only great for the core, but it works your shoulders, chest and hip flexors, too. For beginners, you can modify this exercise by performing the push-up with your knees on the floor.

How to: Start in a suspended plank position just like in the pike exercise, shoulders over hands, feet in the TRX with toes pointing down (a). Bending your elbows to lower your upper body towards the floor, perform the downward half of a push-up. Then, press up to straighten your arms and return to suspended plank position (b). Once you’ve reached the top of the push-up, draw both knees in towards your chest, then extend legs fully back out to return to plank position (c). Repeat.

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3. TRX Hamstring Runners

Hamstring runners look like a mountain climber except on your back. As its name implies, this is a great exercise to fire up those hamstrings. But, since your hips are raised throughout the movement, it’s also good for your glutes, lower back and core. To make this harder, move your feet away from the suspension point to add more resistance. To make it easier, bend both legs in towards your body at the same time.

How to: With the TRX straps at mid-calf length, lie on your back, facing your anchor and place your heels into the foot cradles. Rest your arms flat on the floor alongside your body, palms facing down. Pushing through your heels, lift your hips off the floor (a). Contract your right hamstring to draw that knee in towards your body slowly (b). As you return your leg to the starting position, begin to draw your left knee in towards your body for one rep (c). The TRX straps should remain taut throughout the exercise. Repeat.

4. TRX Side Planks

Just like a regular side plank on the floor, this exercise engages your abdominal muscles, especially the obliques. “The challenge is that your feet are in the TRX — they aren’t on the floor to help you stabilize your body,” says Colavecchio. You can perform the side plank on your elbow (easier) or on your hand (harder).

How to: With the TRX straps at mid-calf, place both feet in the TRX loops and come into a suspended plank position, shoulders over hands, body in a straight line from head to toe (a). Slowly, roll onto your left side so that your left elbow is directly under your left shoulder, top leg will be in front of your bottom leg, core is engaged (b). [The heel of the front foot can touch the toe of the bottom foot.] Keeping your bottom hip lifted to help stabilize your body, reach your top arm towards the ceiling (c). Hold the side plank for 15 seconds (easier) or 30 seconds (harder). Switch sides.

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5. TRX Oblique Crunches

Crunches on the TRX require you to engage not only your main abdominal muscles but also the small stabilizing muscles in your core. If you want to make this exercise harder, Colavecchio suggests performing the oblique crunch at a slow pace. If you’re still working on mastering the TRX crunch (drawing both knees in towards the chest at the same time), Colavecchio recommends that you perform a regular crunch instead.

How to: Start in a suspended plank position, shoulders directly over your hands, feet in the TRX loops, toes facing down and hands directly underneath your shoulders (a). Bend both knees at the same time and draw them together towards your left elbow. Extend both legs straight again to return to plank position (b). Draw both knees towards your right elbow. Extend both legs straight and return to plank position for one rep (c). Repeat.

6. TRX Double Leg Raises

If you want to target those stubborn lower abdominal muscles, try these double leg drops. To make the exercise harder, bring your heels as close to the ground as possible without actually touching the floor. To challenge yourself even more, Colavecchio suggests performing the move with straight legs instead of bent legs.

How to: Adjust the TRX straps so that they are mid-calf length. Lie down on your back with your chest underneath the anchor point, knees bent, feet flat on the floor. Grab the TRX straps, one in each hand and hold them outside of your thighs, hands open, palms facing down on the straps. Keeping your lumbar (lower) spine flat on the ground, push your hands down on the straps, and slowly lift your legs, keeping your knees bent at 90 degrees, until your knees are stacked over your hips, shins parallel to the floor (a). Keep your knees still bent 90 degrees and lower both heels towards the floor (b). Tap the floor with your heels for one rep (c). Repeat.

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7. TRX Body Saw

While the body saw doesn’t look like a difficult exercise, the subtle movement will make your core burn. “It’s often the smaller movements on the TRX that are more challenging,” says Colavecchio. “The goal is to hold a perfect plank the whole time as you rock forward and backwards. You’ll feel your muscles working more when you slide back because you’re changing the center of gravity and that forces you to engage your core more.”

How to: Begin in a suspended forearm plank position, elbows directly underneath your shoulders, hands flat, firmly pressing into the ground, feet in the TRX loops, toes facing down. Engaging your core, rock forward about 2 to 3 inches so that your shoulders are slightly in front of your elbows (a). Then, slide backwards so that your shoulders are about 2 to 3 inches behind your elbows for one rep (b). Repeat.

Originally posted March 11, 2015. Updated May 2017.