Exercise Library
Side Plank
The side plank is an isometric core hold performed on one forearm, training the obliques and deep trunk stabilizers along with the shoulder and hip on the supporting side. Unlike crunches it builds anti-lateral-flexion strength, the ability to resist bending sideways, which carries over to squats, carries, and single-leg work. It requires no equipment and is a standard part of core and lower-back health programs.
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Primary muscle
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Equipment
Bodyweight
Category
Abs
How to Do the Side Plank
- Lie on your side with your legs straight and stacked, supporting forearm on the floor with the elbow directly under the shoulder.
- Place your top hand on your hip or extend it toward the ceiling.
- Brace your core and lift your hips off the floor until your body forms a straight line from head to feet.
- Push the floor away with your forearm so the supporting shoulder stays active, not collapsed.
- Squeeze the glutes and keep the hips stacked vertically, not rolled forward or back.
- Breathe steadily through the hold; do not hold your breath.
- Hold for 20 to 60 seconds, lower with control, then repeat on the other side.
Common Mistakes
- Sagging hips: letting the hips drop breaks the straight line and shifts the work away from the obliques; lift until the body is rigid.
- Rolling the hips forward or backward: rotation changes the exercise and reduces oblique demand; keep shoulders and hips stacked.
- Elbow out of position: an elbow placed ahead of or behind the shoulder strains the joint; keep it directly underneath.
- Holding the breath: isometrics tempt you to brace and stop breathing; keep steady breaths while maintaining tension.
Track This Exercise in the App
Log your side plank sets in 1RM.fit and watch your estimated 1RM update automatically as you get stronger.