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Exercises/Obliques/Bent Knee Side Plank

Exercise

BENT KNEE SIDE PLANK

BeginnerPrimaryObliquesSecondaryAbsGlutes

Form cues

Stack the knees directly on top of each other with both knees bent at roughly 90° for the most stable base.
Keep the hips lifted in a straight diagonal line from the knees to the shoulder — do not let them sag.
Stack the shoulders directly above the supporting elbow throughout.
Breathe steadily — exhale to engage the core harder, inhale to reset.
Animated diagram — illustrative only

About

The bent knee side plank is a beginner-accessible lateral core exercise that supports the body from the forearm and bent bottom knee, training the obliques and lateral stabilisers with reduced load compared to the full side plank.

Common mistakes

What goes wrong — and why

Mistake

Hips sagging toward the floor

Sagging hips remove the lateral core challenge and let the hip muscles rest.

Drive the hips actively upward; if they sag, reduce the hold duration and rebuild.

Mistake

Elbow not under the shoulder

A misaligned elbow changes the leverage and causes unnecessary shoulder joint stress.

Always check that the elbow is positioned directly under the shoulder before lifting the hips.

Mistake

Knees not stacked

Uneven knee placement creates rotational stress through the lower body and destabilises the position.

Stack the top knee directly on the bottom knee before initiating the hold.

Variations · Progressions · Regressions

Adaptations for every level

Regression

Side-Lying Hip Abduction

Lie on the side and lift just the top leg — builds hip abductor awareness before adding the plank hold.

Progression

Full Side Plank

Progress to the full side plank from the forearm and the side of the bottom foot with both legs straight.