Side Plank (Straight-Arm)
The Straight-Arm Side Plank is an isometric core exercise that targets the obliques and lateral stabilizers while challenging shoulder stability. By supporting your body weight on one extended arm, it strengthens the waistline and improves total body balance.
Since this is a time-based isometric hold, the AI analyzes your hold duration alongside your Rate of Perceived Exertion (RPE) to determine if you need to increase the time or add complexity. If your wrist temperature or HRV indicates high systemic fatigue, the system might reduce the target duration to prevent form breakdown. Additionally, if you report wrist pain, the AI immediately suggests the forearm regression to keep you training safely.
Form Cues
- Place your supporting hand directly underneath your shoulder
- Stack your feet and fully extend your legs
- Drive your hips up to create a straight line from head to heels
- Squeeze your glutes and brace your core tightly
- Keep your head neutral and gaze straight ahead
- Don't let your hips sag toward the floor
- Don't allow your top shoulder to roll forward
- Don't place your hand too far out in front of your shoulder
- Don't let your head drop or neck strain
- Don't hold your breath
Common Mistakes
- Sagging hips breaking the straight line
- Hand placed too far forward
- Rotating the torso forward or backward
- Shrugging the supporting shoulder
- Bending the knees
Muscles Worked
This exercise primarily targets the obliques and the quadratus lumborum, which are crucial for lateral spinal stability and preventing lower back pain. Unlike the standard forearm version, the straight-arm position places significant demand on the lateral deltoid and rotator cuff stabilizers, strengthening the shoulder complex while engaging the glutes to maintain hip alignment.
Primary
Secondary
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