Exercise movement reviewed by:Marie Braga, PT, DPT, CSCS

How Iridium Programs This

Iridium analyzes the recovery status of your anterior deltoids before assigning this exercise, as shoulder fatigue can limit your ability to hold the plank position before your core actually hits failure. If your workout history indicates high recent pressing volume, the AI will likely substitute a supine variation to ensure your obliques receive the intended stimulus without the isometric shoulder bottleneck.

Form Cues

Start in a strong high plank with wrists directly under shoulders
Drive your right knee toward your left elbow
Twist your hips slightly to engage the obliques
Keep your hips level with your shoulders
Exhale sharply as you drive the knee across

Don't

Don't hike your hips up toward the ceiling
Don't let your lower back sag or arch
Don't allow your shoulders to drift behind your wrists
Don't bounce your toes off the ground excessively

Common Mistakes

Hiking hips too high
Rushing the tempo
Sagging lower back
Shoulders drifting backward
Not twisting enough

Muscles Worked

This exercise heavily recruits the internal and external obliques through the rotational movement of the hips. It also demands constant isometric contraction from the rectus abdominis to maintain the plank position, while the anterior deltoids and triceps work to stabilize the upper body.