Instructions

1

Lie on your back with knees bent and feet flat on the floor, positioned hip-width apart. Place hands behind your head with elbows pointing outward, or cross arms across chest. Keep lower back neutral with a slight natural curve.

2

Engage your core by drawing your navel toward your spine. Ensure neck remains neutral and chin is not tucked to chest. Feet remain planted throughout the movement for stability.

3

Slowly lower your torso back toward the floor in a controlled manner, allowing the abdominal muscles to lengthen. Maintain contact between lower back and floor. Lower until you reach a comfortable stretched position without fully relaxing.

4

Contract your abdominal muscles and curl your torso upward, lifting shoulders off the floor toward your knees. Focus on the crunch motion driven by core contraction rather than pulling with the neck. Return to starting position in a controlled manner without momentum.

PRIMARY MUSCLESRectus Abdominis

SECONDARY MUSCLESIliopsoas, Rectus Femoris, Obliquus Externus Abdominis

EQUIPMENTBody weight

DIFFICULTYBeginner

Overview

If you want to isolate and overload the Rectus Abdominis, the Frog Crunch is an excellent addition to your routine. The mechanics of this Strength exercise specifically bias the Waist, while the use of Body weight allows for a smooth, natural resistance curve.

Benefits

Allows for a natural movement path that closely mimics functional daily activities.
Utilizes Body weight to create sustained mechanical tension, forcing deep muscle adaptation.
Improves overall Waist stability and proprioception during heavy loads.
Promotes balanced muscular development by effectively recruiting the Rectus Abdominis and associated synergists.
Reduces the likelihood of Waist injuries by reinforcing connective tissue strength.

Common Mistakes

Using excessive momentum to swing the Body weight rather than controlling the eccentric phase.
Losing core tension, leading to poor spinal alignment and reduced power output.
Rushing the repetition tempo instead of focusing on the mind-muscle connection with the Waist.

Muscle Anatomy

The primary driver is the Rectus Abdominis. However, the movement also recruits Iliopsoas, Rectus Femoris, Obliquus Externus Abdominis to maintain control of the Body weight.

Exercise Variations

Dumbbell Frog Crunch
Cable Frog Crunch
Banded Frog Crunch

Beginner Tips

If you are new to the Frog Crunch, focus on mastering the movement pattern with zero weight before adding Body weight.

Frog Crunch