Alternate Bent Leg 45 Degree Extension

Muscles worked

Setup

1. Lie flat on your back on a mat with your spine in a neutral position and arms by your sides.
2. Lift both legs into a 'tabletop' position with knees bent at 90 degrees and shins parallel to the floor.
3. Engage your core by pulling your navel toward your spine and pressing your lower back firmly into the mat.

How to do it

1. Exhale and slowly extend one leg forward and upward at a 45-degree angle until it is fully straight.
2. Inhale as you return the leg to the starting tabletop position with a controlled, slow tempo.
3. Repeat the movement with the opposite leg, alternating sides while keeping the non-moving leg perfectly still.
4. Maintain a steady rhythm, focusing on the tension in your lower abs throughout the entire set.

Form checklist

• Keep your lower back pressed into the floor; do not allow it to arch as the leg extends.
• Maintain a 90-degree bend in the stationary leg while the other leg moves.
• Ensure the extending leg stops at a 45-degree angle to maintain constant tension on the abs.
• Keep your neck and shoulders relaxed to avoid unnecessary tension in the upper body.

Pro tips

• Squeeze the quadriceps of the extending leg at the peak of the movement to maximize leg engagement.
• Focus on the 'hollow body' sensation, imagining you are pulling your hip bones toward your ribs to deepen the abdominal contraction.

Make it harder

• Lower the extension angle closer to the floor (approximately 15-30 degrees) to increase the leverage and core demand.
• Perform the movement with your shoulder blades lifted slightly off the mat in a 'crunch' position to engage the upper abdominals.

Frequently asked

What muscles does the alternate bent leg 45 degree extension work?

The alternate bent leg 45 degree extension primarily targets the abs and obliques, and also works the quadriceps as secondary muscles.

What equipment do you need for the alternate bent leg 45 degree extension?

The alternate bent leg 45 degree extension requires no equipment — just your body weight.

Is the alternate bent leg 45 degree extension good for beginners?

Yes. The alternate bent leg 45 degree extension is a beginner-friendly movement and a strong foundation to build on.

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