Side Plank
The side plank is a held core exercise in which you support your body on one forearm and the sides of your feet, keeping a straight line from ankles to shoulders. It trains the obliques and the deep muscles at the side of the low back to keep the trunk from bending sideways, and the side of the hip on the bottom leg works hard to hold the pelvis level.
Also called: Side Bridge, Lateral Plank, Side Support, Forearm Side Plank · Equipment: bodyweight · Pattern: isolation
Step by step
- Lie on your side with your legs straight and stacked, and prop yourself up on your forearm with your elbow directly under your shoulder and your forearm pointing forward.
- Place your top foot on or just in front of your bottom foot, and rest your top hand on your hip or hold it straight up.
- Press your forearm and the side of your bottom foot into the floor and lift your hips until your body forms one straight line from ankles to shoulders.
- Stack your top hip directly over your bottom hip and your top shoulder over your bottom shoulder, so you are not rolling forwards or backwards.
- Push the floor away with your forearm, keep your shoulder away from your ear, and hold your head in line with your spine.
- Brace your trunk and breathe steadily for the whole hold.
- When your hips can no longer hold the straight line, bring them down to the floor under control, then turn over and hold the other side for the same time.
- One straight line from ankles to shoulders
- Hips up, stacked one over the other
- Elbow under shoulder, push the floor away
- Shoulder away from your ear
- Squeeze the glute on the bottom leg
- Breathe steadily through the hold
In VALDA, these cues are one tap away on the exercise while you train.
What it trains
| Muscle | Role | Evidence |
|---|---|---|
| Obliques (internal/external) | Prime mover | C |
| Quadratus lumborum | Prime mover | C |
| Gluteus medius/minimus: gluteus medius | Secondary | C |
| Rectus abdominis | Secondary | C |
| Transverse abdominis | Stabiliser | C |
| Erector spinae | Stabiliser | C |
| Adductors | Stabiliser | D |
| Lateral deltoid | Stabiliser | D |
| Rotator cuff | Stabiliser | D |
Evidence grades: A = strong research base · B = good · C = limited · D = coaching consensus.
What goes wrong, and the fix
Hips sagging towards the floor
Fix: Lift your hips until ankles, hips and shoulders form one straight line.
Rolling forwards or backwards
Fix: Stack your top hip over your bottom hip and your shoulders one over the other.
Elbow out of line with the shoulder
Fix: Set your elbow directly under your shoulder before lifting your hips.
Shoulder shrugged up to the ear
Fix: Push the floor away with your forearm and draw your shoulder down from your ear.
Holding the breath
Fix: Keep your trunk braced and breathe in and out steadily throughout.
Holding on after the line breaks
Fix: End the set when your hips drop, and progress with a harder version instead.
What the research says
Rehab & prehabGeneral fitnessSport performanceEndurance
- Hold times — Research on trunk endurance tests used the side plank as one of four standard holds and published normal hold times for healthy young adults. Many programmes use sets of about 20–60 seconds per side.
- Left and right — The same research measured each side separately with high repeatability, and comparing left and right hold times is a common use of the test.
- Progression — Holding on the knees is the shorter, easier lever and holding from the feet is harder. Many lifters progress to a top-leg raise or a held weight rather than ever-longer holds.
- Muscle activity — EMG studies show the side plank strongly activates the obliques, the muscles at the side of the low back and the side of the hip on the supporting leg. Activity is not growth, and there is no research on side-plank holds and muscle growth.
- Load and endurance — Research on the repetition continuum finds lighter, longer efforts favour local muscular endurance, which is the side plank's main use.
Swap it mid-workout
With VALDA Pro, FLEX offers alternatives like these when you swap an exercise mid-workout.
Log the side plank in VALDA, with these cues one tap away while you train and your history for it in one place.
General information about exercise technique, not medical advice. If you have an injury or a health condition, your healthcare provider is the right person to ask.