Bent Knee Side Plank

Bent Knee Side Plank trains the trunk to resist unwanted extension or rotation while the body maintains a specific support position.

Primary muscle

Abs

Primary musclesObliques, Transverse abdominis

Secondary musclesGluteus medius, Quadratus lumborum, Shoulders

Equipment

Bodyweight

How to perform Bent Knee Side Plank

Follow the sequence in order, paying attention to the starting position, movement path, and finish described in each step.

For Bent Knee Side Plank, support the body on one forearm or hand with the shoulder stacked above it and the hips facing forward.
Tighten the core as if preparing for a gentle push, squeeze the glutes, and remove any sag or large arch from the lower back.
Breathe behind the brace and hold only while the original body position remains unchanged.
Keep pressure even through the support points and avoid shifting work into the neck, wrists, or lower back.
End the hold under control when the hips rotate, rise, or sag.

End the set when the hips sag, rise, or turn, or when the lower back arches. Do not keep holding just to reach a set time.

Maintain abdominal tension while taking small, regular breaths.

Press through the support points and keep the neck long.

Shorten the body position or use knee support if the shoulders, pelvis, and spine cannot remain aligned.

Holding after position is lost: End the set when the hips sag, rise, or turn, or when the lower back arches. Do not keep holding just to reach a set time.
Collapsing into the shoulders: Press through the support points and keep the neck long.
Stop when the exercise produces sharp, catching, radiating, or increasing joint pain rather than the expected muscular effort.
Alternative Easier Hold: Use the knees, a higher surface, or bent arms or legs to make the hold easier while keeping the same body position.

Place Bent Knee Side Plank after the main compound lifts, in a focused core block, or beside an exercise that does not require a fresh trunk.

Use two to four times per week while accounting for trunk work already supplied by squats, hinges, carries, and overhead lifting.

Goal	Sets	Reps or time	Rest	Effort and execution
Control / technique	2–3	10–20 sec	45–75 sec	Stop well before position changes
Strength / endurance	2–4	20–45 sec	60–90 sec	Stop while 1–3 good-form reps are still possible

Use Bent Knee Side Plank after Barbell Back Squats or Deadlifts so trunk fatigue does not reduce performance on the main lift.
Pair it with Dead Bug or Bird Dog for a focused core block with complementary demands.

Scale the movement