Core · Bodyweight
Frog Crunch
How to do the 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 dropped out wide in a frog position. Crunch your upper body up toward your pelvis, squeezing your abs, then lower under control.
- 1Feel a strong contraction through your upper abs as you curl up
- 2Press your lower back into the floor and lift from the rib cage
- 3Keep your knees relaxed and wide so your hip flexors stay quiet
Common mistakes
- Avoid pulling on your head or neck with your hands
- Don't yank up with momentum; keep it smooth
- Don't let your feet drive the movement instead of your abs
Muscles worked
The frog crunch mainly works the upper abs, with the lower abs and obliques assisting.
- Upper AbsPrimary
- Lower AbsSupport
- ObliquesSupport
- AdductorsMinor
- Hip FlexorsMinor
Kovo programs the 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.