Side Plank (Forearm)
The Side Plank (Forearm) is a fundamental isometric core exercise that targets the obliques and lateral stabilizers of the spine. By holding a rigid position on one side, it builds endurance in the core, hips, and shoulders without placing compressive load on the lower back.
Iridium factors in the high demand on shoulder stability for this movement, using lateral deltoid recovery data to ensure the exercise is not programmed before heavy pressing compounds. Instead of weight-based progression, the algorithm tracks the ratio of hold duration to RPE to systematically increase time targets as your core endurance improves.
Form Cues
- Place your elbow directly under your shoulder
- Stack your feet or stagger them heel-to-toe for balance
- Lift your hips to create a straight line from head to heels
- Squeeze your glutes and brace your abs strongly
- Keep your head neutral and look straight ahead
- Don't let your hips sag toward the floor
- Don't allow your top shoulder to roll forward
- Don't place your elbow too far away from your body
- Don't hold your breath while maintaining tension
Common Mistakes
- Sagging hips due to fatigue
- Rotating the chest toward the floor
- Elbow placement too far forward
- Looking down at feet
- Relaxed glutes reducing stability
Muscles Worked
This exercise primarily strengthens the internal and external obliques and the quadratus lumborum, which are critical for lateral spine stability. It effectively engages the gluteus medius to prevent hip drop and recruits the shoulder stabilizers (serratus anterior and rotator cuff) to support the upper body.
Primary
Secondary
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