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Exercises/Obliques/Side Plank

Exercise

SIDE PLANK

IntermediatePrimaryObliquesAbsSecondaryGlutesDeltoidsLower Back
Stand
Squat

Form cues

Elbow directly under the shoulder — not in front of or behind it
Drive the hip straight up toward the ceiling — do not let it sag or pike
Stack the feet directly on top of each other, or stagger front foot if needed
Body forms one straight diagonal line from head to heel
Breathe normally — do not hold the breath
Keep the top arm extended toward the ceiling or rest it on the hip

The side plank is an anti-lateral flexion core exercise — meaning it trains the ability to resist side-bending forces rather than creating them. It heavily loads the obliques, quadratus lumborum, and gluteus medius, which are critical for spinal stability in rotational sports, single-leg activities, and running. Unlike crunches, it creates no spinal flexion under load, making it a safer and more functional core exercise for people managing lower back issues. Duration and hip height (not sagging) are the two variables to control.


Step-by-step technique

01

Set up on your side

Lie on your side with legs straight. Place the bottom elbow directly beneath your shoulder — not in front. Stack both feet, with the top foot resting on the bottom foot. Keep the head in line with the spine.

Elbow under shoulder, feet stacked
02

Lift the hips

Press through the forearm and the edge of the bottom foot, lifting your hips off the mat. Your body should form a straight diagonal line from the ear through the hip to the ankle. The top arm can extend upward or rest on the hip.

Hips lift to form a straight line
03

Drive the hip upward

Actively press the hip toward the ceiling — do not just stop the sag. The obliques and glute medius on the underside contract to keep the body elevated. Think of lifting the bottom hip as high as possible.

Push hip up, do not just prevent sag
04

Hold and breathe

Maintain the position for the target duration while breathing normally. Keep the neck long — avoid dropping the head or scrunching the neck toward the shoulder. Check the hip line periodically — it should remain elevated.

Breathe normally, hip stays high
05

Lower and switch sides

Slowly lower the hips to the mat. Rest briefly, then rotate to perform the same hold on the opposite side. Both sides should receive equal training time — do not skip the weaker side.

Equal time on both sides

What goes wrong — and why

Mistake

Hip sagging toward the floor

Allowing the hip to drop reduces the oblique activation to near zero — the floor is doing the work rather than the muscles.

If your hip drops, shorten the hold duration and focus entirely on actively pressing the hip up. A shorter hold with correct form is far superior to a long hold with a sagging hip.

Mistake

Elbow not under the shoulder

Placing the elbow forward creates a rotational torque on the shoulder joint and makes maintaining the position mechanically inefficient.

Before lifting, place one finger directly below the shoulder joint to find the correct elbow position. This one adjustment immediately makes the position more stable.

Mistake

Hips rotated forward

Letting the hips rotate so the top hip is in front of the bottom hip turns the side plank into a partial front plank — eliminating the lateral core benefit.

Stack hips vertically. The front of both hips should face the same direction. If stacking the feet makes this hard, stagger the feet instead to improve balance while maintaining hip alignment.


Adaptations for every level

Regression

Side Plank from the Knee

Perform the side plank with the bottom knee on the floor instead of the foot. This reduces the lever arm significantly and makes it achievable for beginners while still training the obliques effectively.

Variation

Side Plank with Hip Dip

From the side plank position, lower the hip toward the floor then drive it back up. Adds dynamic loading to the obliques instead of isometric holds — increasing training intensity for experienced practitioners.

Progression

Star Side Plank

Raise the top leg and top arm simultaneously into a star shape while maintaining the side plank. Dramatically increases the glute medius demand and reduces the base of support, challenging balance and stability.