Exercise guide
Straight Arm Side Plank
- Intermediate
- Compound
- Timed hold
- Waist
This isometric exercise builds exceptional lateral core strength and shoulder stability by challenging the obliques and deltoids to maintain a rigid, elevated torso.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Start in a high plank position with your hands directly under your shoulders and feet hip-width apart.
- Shift your weight onto your bottom hand and rotate your body so you are facing the side.
- Stack your top foot directly on top of your bottom foot, or stagger them for increased stability.
- Extend your top arm straight toward the ceiling, creating a 'T' shape with your arms.
How to do it
- Press firmly through your bottom palm to lift your hips until your body forms a straight line from head to heels.
- Engage your glutes and brace your core tightly to prevent any rotation in the hips.
- Maintain a steady, rhythmic breathing pattern throughout the hold; avoid holding your breath.
- Hold for the prescribed duration, then slowly return to a high plank and repeat on the opposite side.
Form checklist
- Keep the bottom wrist stacked directly under the shoulder to ensure joint alignment.
- Maintain a straight line from the crown of your head through your heels; do not let the hips sag.
- Keep your neck neutral, looking straight ahead or up toward the top hand.
- Squeeze your shoulder blades together slightly to keep the chest open and prevent rounding forward.
Pro tips
- Actively push the floor away with your bottom hand to engage the serratus anterior and stabilize the shoulder complex.
- Imagine a string pulling your top hip toward the ceiling to maximize the contraction of the bottom-side obliques.
Make it harder
- Lift your top leg into the air (Star Plank) to significantly increase the demand on the gluteus medius and core stability.
- Incorporate a 'thread the needle' movement by reaching your top arm under your torso and then back toward the ceiling.
Frequently asked
- What muscles does the straight arm side plank work?
- The straight arm side plank primarily targets the abs, deltoids, and obliques, and also works the erector spinae and serratus anterior as secondary muscles.
- What equipment do you need for the straight arm side plank?
- The straight arm side plank requires no equipment — just your body weight.
- Is the straight arm side plank good for beginners?
- The straight arm side plank is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.
Related exercises
- 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals
- Alternate Knee Raise Side ReachBeginner · abs, deltoids, and obliques
- Alternate Leg Lift Tap Arms CircleIntermediate · abs, deltoids, obliques, and pectorals
- Alternate Single Leg Raise PlankIntermediate · abs, deltoids, hamstrings, and obliques