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  7. Front Leg Lift Under Knee Tap

Exercise guide

Front Leg Lift Under Knee Tap

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

This standing core exercise targets the lower abdominals and hip flexors while engaging the chest and shoulders through a rhythmic clapping motion. It improves balance, coordination, and functional core strength using only body weight.

Reviewed by the Crucible team · Updated June 2026

Watch the Front Leg Lift Under Knee Tap demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Hip flexors

Secondary

  • Abs
  • Glutes
  • Quadriceps

Equipment

  • Body weight

Setup

  1. Stand tall with your feet hip-width apart and your arms extended out to your sides at shoulder height.
  2. Engage your core by drawing your navel toward your spine and maintain a neutral pelvis.
  3. Shift your weight slightly onto your left leg to prepare for the first lift.

How to do it

  1. Exhale as you lift your right leg straight out in front of you while simultaneously bringing both hands together to tap under your thigh.
  2. Inhale as you lower your leg back to the starting position and return your arms to the sides.
  3. Repeat the movement on the left side, alternating legs with each repetition.
  4. Maintain a steady, controlled tempo, focusing on a 1-second lift and a 1-second lower.

Form checklist

  • Keep your chest lifted and avoid rounding your upper back as you reach under the leg.
  • Lift the leg using your core and hip flexors rather than leaning your torso backward.
  • Keep the standing leg slightly soft (not locked) to maintain better balance.
  • Ensure your arms move in a wide arc to maximize engagement of the pectorals and deltoids.

Pro tips

  • Focus on 'crunching' your lower ribs toward your pelvis at the peak of the lift to maximize abdominal contraction.
  • Squeeze your hands together firmly during the tap to increase pectoral and anterior deltoid activation.
  • Maintain a tall spine throughout the movement to ensure the core is doing the work rather than your lower back.

Make it harder

  • Perform the movement with a completely straight leg and pointed toe to increase the lever length and challenge the hip flexors.
  • Increase the tempo to a light bounce to add a cardiovascular element while maintaining strict core control.

Frequently asked

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

Related exercises

  • Barbell Hang CleanAdvanced · erector spinae, glutes, hamstrings, hip flexors, and quadriceps
  • Bodyweight SwingIntermediate · glutes, hamstrings, and hip flexors
  • Deep Squat Reach Forward Reach UpBeginner · glutes, hip flexors, and quadriceps
  • Double Knee Side ThrustIntermediate · glutes, hip flexors, and quadriceps

Train this with a plan, not guesswork

Crucible builds the front leg lift under knee tap into a precise program around your body, equipment, location, and time.

Download on the App Store