Elbow to Knee Crunch
The Elbow to Knee Crunch is a dynamic core exercise that targets the upper abs and obliques by combining a standard crunch with a torso twist. This movement builds rotational core strength and improves coordination between the upper and lower body.
While this is a bodyweight exercise, the AI analyzes your rep consistency and reported RPE to ensure you aren't relying on momentum to complete the movement. If you consistently report lower back discomfort, the system recognizes this pattern and can instantly swap this for a spine-neutral alternative like the Dead Bug. Additionally, by monitoring your daily recovery scores, the app determines the optimal volume for your core training to prevent overtraining the abdominal muscles.
Form Cues
- Press your lower back firmly into the floor throughout the set
- Rotate your entire ribcage towards the knee, not just your arms
- Exhale sharply as you crunch and twist
- Pause briefly at the point of maximum contraction
- Keep your elbows wide and chest open
- Don't pull on your neck or head with your hands
- Don't allow your lower back to arch off the floor
- Don't use momentum to swing your body up
- Don't bring your elbow to the knee by closing your shoulders
Common Mistakes
- Yanking on the neck
- Twisting arms instead of torso
- Rushing the tempo
- Arching the lower back
- Holding breath during exertion
Muscles Worked
This exercise primarily targets the rectus abdominis through spinal flexion and the internal and external obliques through rotation. The hip flexors act as secondary movers to bring the knee toward the chest, creating a comprehensive core contraction.
Primary
Secondary
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