Which Muscles Do Reverse Sit Ups Work?

by Dana Tuffelmire, Demand Media
    Reverse sit-ups target the lower abdominal muscles.

    Reverse sit-ups target the lower abdominal muscles.

    Frustration is inevitable when your sit-up count has reached unfathomable numbers and you still aren't seeing results in your lower abs. When it comes to the lower abs, women have a lot working against them; pregnancy, monthly water retention, hormones and genetics cause many females to give up on a flat, firm physique. The answer could be reverse sit-ups, which target the lower abdominal muscles more than a traditional sit-up or crunch. Speak to a fitness professional to ensure proper form before beginning your reverse sit-up routine.

    Abdominal Muscles

    The abdominal muscle group comprises three separate muscles. The deepest layer, the transversus abdominis, lies at your core, functioning to help keep your internal organs in place and to aide in expelling breath. The oblique muscles run up each side of your body, from ribs to hip, helping your trunk move from side to side. The obliques comprise two layers: external and internal obliques. The largest and most prominent ab muscle is the rectus abdominis, running along the length of your midsection from your ribs to your pubis. The rectus abdominis is separated by cartilage down the middle and horizontally, creating what is known as the "six pack."

    Muscles Worked in a Reverse Sit-Up

    The abdominal muscles are not technically separated into a lower half and an upper half, making it impossible to completely isolate the muscles. However, when you perform a reverse sit-up, the lower portion of the rectus abdominis muscles work harder than the upper portion, and the external obliques work more than the internal obliques. Keep your abdominal muscles balanced to avoid too much strain on your lower back by performing reverse crunches and traditional crunches equally.

    Performing Reverse Sit-Ups

    Perform a reverse sit-up by lying on an exercise mat with your knees raised to your chest, aligning your thighs perpendicular to the mat. Rest your arms at your sides, palms facing down. Pull your knees toward your face by engaging the lower abs, simultaneously lifting your head and neck off the mat. Control your legs with your abs as you return to the starting position and repeat. Complete 10 to 15 repetitions or more as your lower abs gain strength. Challenge yourself by performing a reverse sit-up with straight legs, or lift and lower your legs while squeezing an exercise ball between your calves.

    Beware the Hip Flexors

    Hip flexor muscles include the psoas major, illiacus, rectus femoris, pectineus and sartorius. The hip flexors connect your legs to your trunk and are easily employed as you lift and lower your legs during a reverse crunch. Avoid strengthening your hip flexors instead of your lower abdominals by concentrating on engaging your pelvis during a reverse crunch. Inhale before you begin, then exhale as you pull your belly button in toward your spine and pull your knees to your chest. Inhale as you return to the starting position.

    About the Author

    Dana Tuffelmire has been writing for DMS for three years. She taught elementary school for seven years and earned a master’s of education degree with a specialization in literacy. She is currently a stay-at-home mom to two sons. Her dream is to one day write a children's book.

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