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Kneeling Side Crunches

Kneeling side crunches work one side of the waist at a time: from tall kneeling, the torso side-bends as the elbow drives down toward the hip, shortening the obliques against gravity. They suit trainees who want direct oblique work without lying down or hanging from a bar. Coached by Maddy (NASM-CPT) — these are the exact form cues he gives on every client's first week.

Muscles worked

Obliques Abs · rectus abdominis Deep core · transverse abdominis

Sets & reps by goal

GoalSets × RepsRest
Strength4 × 5–6 per side (pause at the bottom)90 s
Muscle3–4 × 9–12 per side60–90 s
Endurance3 × 18–25 per side45–60 s

Rep ranges per Helms 2014 · Schoenfeld 2016.

Level — Beginner

Beginner — the strictness of the pure side plane is the real skill to master.

Proper form — 5 cues

  1. Kneel tall with hands behind the ears, elbows wide open.
  2. Side-bend straight over the working side — think elbow to hip pocket, not forward folding.
  3. Feel the ribs sink toward the hip on the crunching side while the other side lengthens.
  4. Return to fully upright kneeling before the next rep — the lengthening half counts too.
  5. Finish all reps on one side, then match them exactly on the other.

Breathing: Exhale as the elbow sinks toward the hip, inhale on the return to tall kneeling.

The 3 mistakes Maddy corrects most

Twisting forward instead of bending sideways. Rotation changes the exercise and lets the stronger front abs steal the obliques' work. Fix: Imagine sliding between two panes of glass — movement lives purely in the side plane.
Sinking the hips toward one heel. Pelvis shift fakes range while the waist barely shortens. Fix: Keep hips stacked over the knees; only the torso travels.
Small, rushed dips. Partial side-bends never take the oblique through a full shorten-lengthen cycle. Fix: Slow to two seconds per rep and chase visible distance between rib and hip.

Common questions

Do side crunches slim the waist?

They strengthen and build the oblique muscles; they do not selectively burn the fat covering them — no exercise spot-reduces. A stronger, denser waist plus lower overall body fat is what changes the mirror. Train the movement for function and let nutrition drive the fat side of the equation.

Why do these from kneeling rather than standing?

Kneeling fixes the lower half in place, so the pelvis cannot sway to assist and every centimetre of side-bend must come from the trunk. Standing versions allow subtle hip shifts that dilute the work. The kneeling base is simply the stricter classroom for the same movement.

Should I add weight to side crunches?

Once bodyweight sets pass about fifteen strict reps per side, holding a light dumbbell at the shoulder on the working side restores the challenge. Add load in small steps — obliques respond well to moderate weight and full range, and heavy sloppy side-bends mostly train bad habits.

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