Core · Bodyweight
Alternate Frog Crunch
How to do the alternate frog crunch, the muscles it works, and the mistakes to avoid. Pulled straight from the Kovo app's exercise library.
- Equipment
- Bodyweight
- Difficulty
- Beginner
- Logged as
- Reps
- Movement
- Flexion
- Mechanic
- Isolation
How to do it
Lie on your back with the soles of your feet together and knees splayed out to the sides in a frog position. Place your hands behind your head and crunch up, bringing one elbow toward the opposite side as you twist. Lower under control, then alternate the twist to the other side on the next rep. Keep your lower back pressed into the floor throughout.
- 1Your abs contracting as you curl your shoulders off the floor
- 2Your obliques working as you twist toward each side
- 3A controlled squeeze at the top of every rep
Common mistakes
- Pulling on your neck with your hands
- Yanking up with momentum instead of crunching
- Letting your lower back arch off the floor
Muscles worked
The alternate frog crunch mainly works the upper abs and obliques, with the lower abs and hip flexors assisting.
- Upper AbsPrimary
- ObliquesPrimary
- Lower AbsSupport
- Hip FlexorsSupport
- AdductorsMinor
Kovo programs the alternate frog crunch for you and tracks it every session.
We build your whole program, drop the right lifts into each workout, and adjust your weights as you get stronger. Free on iOS and Android.
More abs & core exercises
- How to do the ab wheel rollout
- How to do the ankle tap plank
- How to do the ankle taps
- How to do the resistance band dead bugs
- How to do the resistance band pallof press
- How to do the rollout
Last reviewed June 2026.