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  1. Home
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  3. Exercises
  4. /
  5. Core & Abs
  6. /
  7. Lying Single To Double Toe Tap

Exercise guide

Lying Single To Double Toe Tap

  • Beginner
  • Compound
  • Rep-based
  • Upper legs
  • Waist

This dynamic core sequence combines single-leg and double-leg reaches to target the entire abdominal wall and obliques while requiring hip flexor and quadriceps stability. It builds coordination and sustained tension through varying leverage points.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Lying Single To Double Toe Tap demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Hip flexors
  • Quadriceps

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat with your legs fully extended and arms reaching overhead.
  2. Press your lower back firmly into the floor to eliminate any arch in the spine.
  3. Position your feet together and engage your quads to keep your legs straight.

How to do it

  1. Exhale as you lift your right leg and reach both hands toward your right toes, crunching your shoulder blades off the floor.
  2. Inhale as you lower back to the start, then repeat the movement lifting only your left leg.
  3. Exhale and lift both legs simultaneously while reaching both hands toward your toes for a full V-up crunch.
  4. Lower back to the starting position with a controlled 2-second eccentric phase and repeat the sequence.

Form checklist

  • Keep your lower back in contact with the mat during the single-leg phases.
  • Avoid using momentum or swinging your arms to pull yourself up.
  • Keep your legs as straight as possible to maximize quadriceps and lower ab engagement.
  • Tuck your chin slightly toward your chest to prevent neck strain.

Pro tips

  • Focus on 'peeling' your spine off the floor one vertebra at a time rather than jerking upward.
  • Maintain a slight 'hollow body' tension even at the bottom of the movement to keep the abs under constant load.
  • Squeeze your inner thighs together during the double-leg tap to increase pelvic floor and lower abdominal recruitment.

Make it harder

  • Keep your heels and shoulder blades hovering 2 inches off the floor throughout the entire set.
  • Hold a light medicine ball or dumbbell between your hands to increase the resistance on the upper abdominals.

Frequently asked

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

Related exercises

  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals
  • 90 To 90Beginner · abs, glutes, obliques, and quadriceps
  • 90 To 90 SwitchIntermediate · abs, glutes, obliques, and quadriceps
  • Air BikeIntermediate · abs and obliques

Train it with Crucible Fit.

Every movement in this library is in the app with video and instructions, ready for your own sessions on the days between Crucibles. Your first Crucible is on us.

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