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Side Boat Knee to Elbow Touch

From a side boat position, this drill draws the top knee and top elbow together in a lateral crunch, then re-lengthens the whole line. It layers a dynamic oblique contraction on top of an already demanding hold, making it one of the toughest side-core moves in a bodyweight-only library. 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 × 4–6 touches per side, slow90 s–2 min
Muscle3 × 8–12 touches per side60–90 s
Endurance3 × 14–18 touches per side45–60 s

Rep ranges per Helms 2014 · Schoenfeld 2016.

Level — Advanced

Advanced — the moving limbs shrink your base of support while the load stays on one forearm and foot.

Proper form — 5 cues

  1. Set the side boat: forearm down, hips lifted, body in one straight diagonal
  2. Extend the top arm overhead and the top leg long
  3. Sweep the top knee and elbow toward each other above your waist
  4. Touch, squeeze the obliques for a beat, then reach both limbs long again
  5. Keep the hips lifted at full height for every single rep

Breathing: Exhale as knee and elbow meet, inhale as the body reaches long.

The 3 mistakes Maddy corrects most

Dropping the hips during the knee-to-elbow sweep. The moment the pelvis dips, the bottom obliques stop resisting collapse and the crunch loses its platform. Fix: Treat hip height as the rep's pass-fail test — if it drops, pause, re-set the boat, and continue with fewer reps.
Rolling chest-down toward the floor to meet the knee. Turning the torso converts the lateral crunch into a front crunch and takes the obliques out of their strongest line. Fix: Keep the chest facing the wall in front of you; knee and elbow meet in the side plane, not underneath you.
Tapping knee to elbow without any squeeze. A touch without contraction is choreography — the oblique shortening under control is where the training effect lives. Fix: Pause for one second at the touch and deliberately crunch the waist before re-extending.

Common questions

What comes first — this exercise or the side boat leg raise?

The leg raise version is the natural stepping stone. It keeps the torso still and moves only the leg, while the knee-to-elbow touch moves both ends of the body toward each other and demands far more balance. Progress from side plank, to leg raise, to knee-to-elbow as each stage becomes controlled.

Does this exercise reduce love handles?

It strengthens and builds the oblique muscles underneath, but no exercise removes fat from one chosen spot — fat loss is a whole-body outcome driven by your overall calorie balance. Train this for a stronger, more athletic waist, and manage nutrition for the leanness that makes it visible.

How many reps of side boat knee-to-elbow should I do?

Quality collapses quickly on this drill, so program modest numbers: three sets of eight to twelve controlled touches per side suits most strong trainees. The set ends when the hips start dipping or the touch turns into a swing — stopping there is what keeps the exercise productive.

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