Seated Alternate Knee Tuck

Muscles worked

Setup

1. Sit on the long edge of a flat bench with your legs extended in front of you.
2. Lean your torso back at a 45-degree angle and grip the edges of the bench behind your hips for support.
3. Lift both feet slightly off the floor, engaging your core to find your balance point on your sit bones.

How to do it

1. Exhale as you pull your right knee toward your chest, keeping the left leg extended and hovering off the floor.
2. Inhale as you slowly extend the right leg back to the starting position with control.
3. Immediately repeat the movement with the left leg, alternating sides in a fluid, rhythmic tempo.
4. Maintain a steady pace, ensuring your feet never touch the ground between repetitions.

Form checklist

• Keep your chest lifted and shoulders back to avoid rounding your spine.
• Maintain a constant 'V' shape between your torso and thighs to keep the abs under tension.
• Ensure the movement comes from the hips and core, not by swinging the lower legs.
• Keep your neck neutral by looking slightly forward rather than at your feet.

Pro tips

• To maximize oblique activation, slightly rotate your torso toward the knee that is tucking in.
• Focus on the mind-muscle connection by imagining your lower abs pulling your thigh toward your ribs.
• Keep your toes pointed to maintain full leg tension and better control the movement.

Make it harder

• Perform the exercise without holding the bench, extending your arms out to the sides to challenge your balance.
• Slow the tempo down to a 3-second extension phase to increase the time under tension for the rectus abdominis.

Frequently asked

What muscles does the seated alternate knee tuck work?

The seated alternate knee tuck primarily targets the abs and obliques, and also works the hip flexors as secondary muscles.

What equipment do you need for the seated alternate knee tuck?

The seated alternate knee tuck requires no equipment — just your body weight.

Is the seated alternate knee tuck good for beginners?

Yes. The seated alternate knee tuck 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