Alternating 45-Degree Bent-Leg Extension
Strengthen your core! Alternating leg extensions target abs & hip flexors. Perfect for all fitness levels, no equipment needed.
The Alternating 45-Degree Bent-Leg Extension mainly works the core. No equipment needed: it uses just your bodyweight.
Optional Equipment

Alternating 45-Degree Bent-Leg Extension Muscles Worked
Primary
Abdominals (rectus abdominis); Obliques
Secondary
Hip Flexor (iliopsoas)
Alternating 45-Degree Bent-Leg Extension Variations and Alternatives
How to do the Alternating 45-Degree Bent-Leg Extension
Lie flat on your back on a mat with your knees bent at 90 degrees and your feet lifted off the floor. Ensure that your lower back is in a neutral position, slightly touching the mat.
Place your hands flat on the floor beside your hips for stability.
Brace your core and keep your chin slightly tucked to maintain a neutral spine throughout the movement.
Slowly extend one leg out straight so that it is at a 45-degree angle to the floor while the other knee remains bent above your hips.
Hold the position for a beat and then return your extended leg to the starting position.
Alternate and extend the opposite leg in the same manner, ensuring a smooth and controlled motion.
Continue alternating legs for the desired number of repetitions, maintaining controlled breathing and keeping your core engaged throughout the exercise.
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Alternating 45-Degree Bent-Leg Extension FAQs
What muscles does the Alternating 45-Degree Bent-Leg Extension work?
The Alternating 45-Degree Bent-Leg Extension mainly works the core. The main muscles are the rectus abdominis and obliques.
What equipment do you need for the Alternating 45-Degree Bent-Leg Extension?
None. The Alternating 45-Degree Bent-Leg Extension is a bodyweight exercise, so you can do it anywhere.
What are some Alternating 45-Degree Bent-Leg Extension variations and alternatives?
Similar exercises include the Alternating 45-Degree Backward-Lean Knee Raise, 90-Degree Heel-Tap, Alternating Leg Pull and Alternating Toe-Tap Leg Lift.
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