How to Do Crunches Like a Total Pro

Amy Eisinger, M.A., C.P.T.
·8 min read

Chances are, you already have an idea of how to do crunches. The classic abs exercise is one that you probably did at some point in a high school gym class or even while working out on your own.

Core exercises, like crunches, can be great at engaging your rectus abdominus—those muscles on the front of your body responsible for “six-pack abs.” But if you learn how to do crunches properly, you’ll go beyond just those muscles, also engaging your spine and some of the deeper core muscles that you have. And while there’s nothing wrong with doing crunches, know that exercises like planks can also be great for strengthening and stabilizing your core musculature.

With that in mind, let’s jump in to everything you need to know about how to do crunches.

What Is a Crunch

Crunches are one of the most popular abs exercises around, and they’re considered a foundational movement. A foundational movement is a basic exercise on which it's easy to build. For instance, once you master crunches, you can experiment with countless variations, like bicycle crunches, tuck-ups, and more. (We provide directions for several types of crunches  below.)

Quick refresher: A basic crunch is a bodyweight abdominal exercise done while lying faceup on the floor. In short, you’ll contract your abs, then lift your shoulders and head a few inches off the floor (see our step-by-step instructions on exactly how to do crunches below). 

Like all exercises, crunches require recruitment of certain muscle groups and place a strain on other muscles. You should avoid doing crunches if you have frequent back pain, neck pain, or if you’ve been instructed to avoid crunches by a doctor.

Benefits of Crunches

Doing crunches on a regular basis can help strengthen your abdominal muscles—but crunches can also do much more. Incorporating crunches into your workout routine can also help build better posture, since you need strong core muscles to stand up straight. In turn, having  good posture and a strong core means you're less susceptible to low back pain, or back injuries in general. A strong core can also help with certain endurance events, like running, swimming, or cycling. It's true! You need strong abdominal muscles to maintain proper form during longer bouts of exercise. Your core is responsible for so many daily movements and you can help strengthen it by doing crunches.

Having said that, crunches are not a miracle exercise. If you’re looking to build “six-pack abs,” no amount of crunches alone will get you there.

Remember that weight loss is complicated, and if you’re looking to lose weight or “flatten” your stomach, exercise is only one small part of the equation. Eating healthy foods, getting adequate sleep, and working with a doctor or dietitian are all a good idea if sustainable weight loss is a goal. Also, your weight is dependent on a number of other factors that can be out of your control, including hormones, genes, and more, which is important to keep in mind. Bottom line: While there are lots of benefits to crunches, automatic weight loss or washboard abs isn’t one of them. (It's also worth noting that gaining a six pack is incredibly difficult and there's no reason it needs to be a goal of yours, or most people's, really). 

Crunches work your rectus abdominis (the long, flat muscle on the front of your torso), plus your internal and external obliques (the muscles that wrap around the side of your body). Crunches will also help engage your transverse abdominis, which are your inner-most core muscles. 

How to Do Crunches

<h1 class="title">classic abs crunch</h1><cite class="credit">Katie Thompson</cite>

classic abs crunch

Katie Thompson

If you’re performing crunches correctly, you should be putting very little strain on your neck, shoulders, and low back. Here's how to do a basic abdominals crunch:

  1. Lie faceup on the floor with your knees bent and feet flat on the floor. Place your hands behind your head, allowing your elbows to bend out to the sides.

  2. Contract your core so that your low back gently presses against the floor. This is your starting position.

  3. From here, exhale as you lift your head and shoulders a few inches off the floor, contracting your abs. Be careful to not strain your neck, scrunch your shoulders, or pull your neck forward with your hands.

  4. Now, breathe in as you slowly lower back to your starting position with control.

  5. Repeat in this manner for a set amount of time or reps.

Types of Crunches

Once you’ve mastered the basic crunch, there are plenty of variations you can try to keep your workouts interesting. For starters, select two or three of the below exercises and try doing 12-16 reps for three sets. Add them to your normal workout routine two to three times per week.

Bicycle Crunch

<cite class="credit">Katie Thompson</cite>
Katie Thompson
  • Lie faceup with your legs in tabletop position (knees bent 90 degrees and stacked over your hips). Place your hands behind your head, elbows bent and pointing out to the sides. Use your abs to curl your shoulders off the floor. This is the starting position.

  • Twist to bring your right elbow to your left knee, while simultaneously straightening your right leg.

  • Then, twist to bring your left elbow to your right knee, simultaneously straightening your left leg. This is 1 rep.

  • Continue alternating sides. Go at a slow and steady pace so that you can really twist and feel your abs working.

Butterfly Sit-Up

<cite class="credit">Katie Thompson</cite>
Katie Thompson
  • Lie faceup with either hands behind your head and elbows bent out to the sides, or hands crossed across your chest; and soles of the feet touching so that your knees fall open to the sides. Contract your core, so that your low back gently presses against the floor. This is your starting position.

  • From here, do a sit-up, by contracting your core, exhaling as you roll up, and coming all the way to a seated position while feet remain stationary.

  • Slowly lower your body back down to the mat as you inhale, moving with control. Repeat for a set number of reps or amount of time.

Alternating Toe Touch Crunch

<h1 class="title">alternating toe touch crunch january 2020 challenge delise</h1><cite class="credit">Katie Thompson</cite>

alternating toe touch crunch january 2020 challenge delise

Katie Thompson
  • Lie faceup with your legs extended straight up to the ceiling, feet flexed.

  • Crunch up, reaching your fingertips toward your flexed toes. Engage your core and focus on keeping your low back pressed into the floor (you’re not lifting your hips, you’re only lifting your shoulders and upper back off the floor).

  • Return to starting position and repeat, leaving legs in the same place throughout the move.

Bird-Dog Crunch

<h1 class="title">bird-dog crunch january 2020 challenge morit</h1><cite class="credit">Katie Thompson</cite>

bird-dog crunch january 2020 challenge morit

Katie Thompson
  • Start on your hands and knees in tabletop position with your wrists stacked under your shoulders and your knees stacked under your hips.

  • Extend your right arm forward and left leg back, maintaining a flat back and keeping your hips in line with the floor. Think about driving your foot toward the wall behind you.

  • Squeeze your abs and draw your right elbow and left knee in to meet near the center of your body.

  • Reverse the movement and extend your arm and leg out.

  • Continue this movement for a set amount of time or reps, then repeat on the other side.

Jackknife Crunch

<h1 class="title">jackknife crunch january 2020 challenge delise</h1><cite class="credit">Katie Thompson</cite>

jackknife crunch january 2020 challenge delise

Katie Thompson
  • Lie faceup with your arms extended overhead and legs straight against the floor. Contract your abs to press your low back into ground. This is your starting position.

  • Point your toes, squeeze your thighs together, squeeze your glutes, and lift your right leg and left hand off the ground, reaching your hand forward and across to tap your foot so that your body forms a V.

  • Keep your core engaged as you slowly lower to return to starting position. Continue on the same side for a set amount of time or reps, then repeat on the other side.

Standing Crunch

<h1 class="title">Standing Crunch - Lauren Leavell</h1><cite class="credit">Katie Thompson </cite>

Standing Crunch - Lauren Leavell

Katie Thompson
  • You can do this move with or without a resistance band. Stand with your feet just wider than hip-width, with your left hand on your hip and right hand straight up toward the ceiling.

  • Engage your core as you lift your right knee and pull your right elbow down to meet it. Your knee should come to about hip height, and your elbow should tap your knee there.

  • You shoulder feel this in your obliques as a standing crunch, engaging your core to help with balance.

  • Return to your starting position by putting your right foot back on the floor and extending your right arm overhead. Focus on placing your right foot gently down—not just letting it slam to catch yourself from falling.

  • Do all the reps on one side, then repeat on the other side.

Common Crunches Mistakes to Avoid

As mentioned, one of the most common mistakes is that people often strain their neck by tightening it, or pull their neck forward with their hands as they curl up. Another common mistake is breathing incorrectly during the exercise. You can actually make the exercise less effective and more challenging by inhaling or holding your breath as you crunch up. 

Likewise, you should not try to move as fast as possible—using momentum to curl your torso up and down. When performed slowly, with control, and with proper breathing, crunches can be an effective abs exercise.

Originally Appeared on SELF