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  7. Frog Crunch Feet Together

Exercise guide

Frog Crunch Feet Together

  • Beginner
  • Compound
  • Rep-based
  • Waist

The Frog Crunch isolates the abdominals by opening the hips, which reduces hip flexor recruitment and forces the core to drive the movement. This variation is excellent for targeting the rectus abdominis while providing a slight stretch to the adductors.

Reviewed by the Crucible team · Updated June 2026

Watch the Frog Crunch Feet Together demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Hip flexors

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with your spine in a neutral position.
  2. Place the soles of your feet together and let your knees fall open to the sides, creating a diamond shape with your legs.
  3. Slide your heels toward your glutes as far as is comfortable.
  4. Lightly place your fingertips behind your ears, keeping your elbows wide.

How to do it

  1. Exhale and contract your abdominals to lift your head, neck, and shoulder blades off the floor in a smooth motion.
  2. Focus on pulling your ribcage down toward your pelvis while keeping your lower back pressed into the mat.
  3. Inhale as you slowly lower your upper body back to the starting position using a 2-second eccentric tempo.
  4. Maintain the 'frog' leg position throughout the entire set without letting your knees collapse inward.

Form checklist

  • Keep your lower back glued to the floor to protect the lumbar spine.
  • Avoid pulling on your neck; keep a space the size of an orange between your chin and chest.
  • Ensure your knees stay flared out to minimize hip flexor involvement.
  • Keep your elbows back and out of your peripheral vision.

Pro tips

  • Visualize 'peeling' your spine off the floor one vertebra at a time to maximize the mind-muscle connection with the rectus abdominis.
  • Pause for one second at the top of the movement to achieve a peak contraction.

Make it harder

  • Lift your feet a few inches off the floor while maintaining the soles-together position to increase lower abdominal engagement.
  • Extend your arms straight overhead to increase the lever length and resistance.

Frequently asked

What muscles does the frog crunch feet together work?
The frog crunch feet together primarily targets the abs and obliques, and also works the hip flexors as secondary muscles.
What equipment do you need for the frog crunch feet together?
The frog crunch feet together requires no equipment — just your body weight.
Is the frog crunch feet together good for beginners?
Yes. The frog crunch feet together is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • 3/4 Sit-UpBeginner · abs and obliques
  • 45 Degree Bicycle Twisting CrunchIntermediate · abs and obliques
  • 45 Degree Lean Back Alternate Knee RaiseBeginner · abs and obliques
  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals

Train this with a plan, not guesswork

Crucible builds the frog crunch feet together into a precise program around your body, equipment, location, and time.

Download on the App Store