Can’t do a sit-up? A personal trainer recommends these three alternative exercises to strengthen your abs

Work towards a sit-up with these essential moves

A woman performs assisted sit-ups in a park. Her feet are hooked under a metal pole, her knees are bent and she is sitting up with her hands clasped behind her head. She is smiling broadly; behind her we see a sandy area and grass.
(Image credit: Getty Images)

Many of my personal training clients list performing a full sit-up as one of their fitness goals. This gym class throwback may be a basic and well-known exercise, but it’s hardly an easy one.

Sit-ups require optimal strength in nearly all of your core muscles, specifically the rectus abdominis (also known as the six pack), the transverse abdomins (the deepest abdominal muscle), and the internal and external obliques (muscles located on each side of the torso). When these muscles aren’t properly conditioned, executing proper form on a sit-up is nearly impossible.

If you’ve just begun a fitness routine and want to work towards sit-ups, start with these three essential exercises to build your core strength. The only piece of equipment you’ll need is a mat for support and comfort.

Crunch

AB EXERCISE - How to do an abdominal crunch (ab crunch) - YouTube AB EXERCISE - How to do an abdominal crunch (ab crunch) - YouTube
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Sets: 3 Reps: 12-15

  • Lie on your back with your knees bent and feet planted on the mat. Place both hands behind your head for support or across your chest.
  • Engage your core and slowly lift your head and shoulders off the mat.
  • Once you’ve reached the end of your range, hold for two to three seconds.
  • Lower your head and shoulders with control.

Trainer tips: Avoid using your hands to pull your head off the mat—rely on your core to do the work. Don’t allow the lower back to arch excessively as you move.

Alternating heel tap

Heel taps - YouTube Heel taps - YouTube
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Sets: 3 Reps: 12-15 on each leg

  • Lie on your back with your knees bent and feet on the floor.
  • Lift both of your knees to a tabletop position, with your shins parallel to the ceiling and your knees at a right angle.
  • Slowly lower your left heel towards the floor, maintaining the right angle at the knee.
  • Tap the ground then bring the leg back to the starting position.
  • Repeat on the opposite side.

Trainer tips: Keep your spine in a neutral position and don’t allow the lower back to arch off the ground when lowering your heel to the floor. Place your hands underneath your lower back for support if needed. To progress this exercise, lower both heels towards the floor simultaneously.

Assisted sit-up

Anchored Sit Up - OPEX Exercise Library - YouTube Anchored Sit Up - OPEX Exercise Library - YouTube
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Sets: 3 Reps: 5-8

  • Anchor your feet under something sturdy, like a couch or heavy free weights, then lie on your back with your knees bent and your arms across your chest.
  • Using your anchored feet for leverage and support, slowly lift your head, shoulders, and torso off the mat so you're in a seated position. The movement should come from your core.
  • Lower your body back down on the mat with control then repeat.

Trainer tip: Avoid using momentum to propel yourself off of the mat. For an extra challenge, lower yourself back down to the mat at a slower pace.

Jennifer Rizzuto
Writer

Jennifer Rizzuto is a freelance fitness journalist based in New York, NY. She’s been a NASM-certified personal trainer, corrective exercise specialist, and performance enhancement specialist for over a decade. She holds additional certifications in nutrition coaching from Precision Nutrition, and pre/post-natal exercise from the American Council on Exercise. As the daughter of a collegiate football coach who was never any good at sports, she understands how intimidating it can be to start an exercise regimen. That’s why she’s committed to making fitness accessible to everyone—no matter their experience level.