Side Plank
Turn a plank on its side and the obliques inherit the whole job. The side plank trains lateral core strength — resisting the trunk's collapse toward the floor — along with the quadratus lumborum and the hip stabilizers of the bottom leg, a combination spine researchers rate among the most valuable and back-friendly core exercises. It also finds left-right imbalances instantly: most people wobble far more on one side.
How to do the side plank, step by step
- Lie on your side with your forearm on the floor, elbow directly under the shoulder.
- Stack your feet, or stagger them heel-to-toe for more stability.
- Lift your hips until your body forms a straight line from head to ankles.
- Push the floor away through the forearm so the shoulder stays active, not sunken.
- Hold the line, breathing steadily, without letting the hips drift back or drop.
- Lower with control and repeat on the other side.
Form cues that fix most reps
Push the hips up and slightly forward — the most common leak is drifting into a jackknife.
Press the floor away through the elbow; a sagging shoulder ends the hold early.
One straight line from ear to ankle — imagine being pressed between two panes of glass.
Common mistakes (and the fix)
Side Plank sets and reps
Match the rep range to your goal, not the other way around. These are the standard evidence-based ranges:
| Goal | Sets × Reps | Rest |
|---|---|---|
| Strength | 3–5 × 3–6 | 2–3 min |
| Muscle growth | 3–4 × 8–12 | 60–90 sec |
| Endurance | 2–3 × 15–20 | 30–60 sec |
Side Plank FAQ
What muscles does the side plank work?
The obliques and the quadratus lumborum on the bottom side work hardest, resisting lateral flexion, with the shoulder stabilizers of the supporting arm and the glute medius of the bottom hip holding everything in line. It is the standard exercise for lateral core strength.
How long should I hold a side plank?
2 to 3 holds of 20 to 45 seconds per side is an effective dose. If one side gives out much sooner, give the weak side an extra set each session until the gap closes — that asymmetry is worth fixing.
Is the side plank good for lower-back health?
It features in well-known spine-stability programs because it trains the lateral trunk hard while placing relatively little compressive load on the spine. That reputation is encouraging, not a prescription — if you have active back pain, use pain-free durations and progress gradually.
More core exercises
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