5 Exercises for Fully Defined Ab Muscles

Sophia McDermott Drysdale


Brazilian Jiu Jitsu, Bodybuilding, Nutrition, Women's Fitness

We are bombarded with magazine ads, infomercials, and Instagram pictures of fit looking people with shiny, rippling washboard abs. Most media hype would have you believe that in order to obtain that illustrious six-pack, endless sit ups are the answer. In reality, regardless if you are a guy, girl, or a new mother looking to tighten her tummy, doing endless sit-ups is not the way to get fully defined abdominal muscles.


Workouts, strength and conditioning, core strength, abdominals, six pack

Male or female - doing sit-ups is not going to get you greater ab definition.



The rectus abdominis is the "abs" muscle: a paired muscle that runs vertically on each side of the anterior wall of the abdomen, separated by a band of connective tissue. Tendinous intersections run across the muscle horizontally, giving the muscle eight distinct looking muscle bellies. We all refer to the rectus abdominis as a six pack, when in fact, an eight pack is structurally a much more apt description. Sit-ups have become the go-to exercise for training the abs because they work the rectus abdominis. But the reason the full eight-pack isn’t visible on most athletes who do them is because sit-ups over-engage the hip flexors, neglecting the lower abdominal muscles below.


Why Sit-Ups Don't Work

The rectus abdominis are initially engaged in the sit-up, but as you rise higher throughout the sit-up movement, the hip flexors take over. The movement particularly over-engages the hip flexors when the feet are lodged under something to hold them in place. Another common group of exercises used to target the lower abs are knee-ups and hanging leg raises. More often than not, these exercises also engage the stronger hip flexors, rather than the lower aspects of the rectus abdominis.


5 Exercises for Fully Defined Ab Muscles

The key to engaging the rectus abdominis all the way through to target the lower muscles near your pelvis is to keep your hips isolated. Your lower abdominals need to be contracted the entire time and your transverse abdominis needs to be braced to support your spine. This allows you to focus on performing the crunch movement and engaging your rectus abdominals all the way through.


Perform the five exercises below to fully engage the lower portion of the rectus abdominis, isolate the hips, and get well on your way to achieving fully defined abs.


1. Angry Cat, Happy Cat

This is a great exercise if you’re just getting started.



  • Start on your hands and knees with the knees in line with the hips and the hands in line with the shoulders.
  • Curl your spine by crunching your abs hard (hold for 3 seconds), then arch your back (hold for another 3 seconds).
  • Perform 20 repetitions.


2. Baby Crunches


  • Activate your transverse abs by pressing the middle of your back into the floor.
  • Perform small crunches and keep your shoulders off the floor or mat. Never allow your abdominals to relax.
  • Perform 20 repetitions.


3. Crunches on Medicine Ball


  • Roll down the ball until only your upper back is supported.
  • Engage your transverse abs and glutes by keeping your hips up.
  • Perform small crunches while keeping your hips up the entire time. Don’t drop your hips – if you do, as you crunch up you will not be contracting your lower rectus abdominis, transverse abdominis, or your glutes.
  • Perform 20 repetitions of each.


4. Floor Crunches with Raised Legs

This is a great exercise to engage the lower abs as they need to work to stabilize the hips since your feet are not resting on the floor.



  • Activate your transverse abs by pressing the middle of your back into the floor.
  • Perform small crunches and keep your shoulders off the floor or mat. Never allow your abdominals to relax.
  • Perform 20 repetitions.


5. Toes to the Ceiling

This is a pretty challenging exercise. The challenge is to be able to elevate your toes towards the ceiling without creating momentum or swinging your legs towards you.



  • Activate your transverse abs by pressing the middle of your back into the floor and lift shoulders off the floor or mat.
  • By contracting your lower abs, lift your toes towards to ceiling. These movements should be small since you are only engaging your lower abs to perform the movement.
  • Never allow your abdominals to relax.
  • Perform 20 repetitions.


You're Risking Muscular Imbalance, Too

Overuse of the hip flexors explains why people who train a lot and work out super hard only ever have the top four sections of their abs showing. In their so-called specific exercises, the lower four sections aren't being engaged - instead, the hip flexors are doing the work. Over time, this can also cause postural and lower back issues due to muscular strength imbalances.


Don't let it be you. Incorporate these five exercises into your training routine and you'll be well on your way to the ab definition you're looking for.


This article was originally published on Breaking Muscle AU.


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