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Plank Knee to Elbow Touch

This plank variation draws one knee across and up to touch the same-side elbow outside the body line, folding oblique work into the standard plank hold. It suits trainees who want side-trunk strength without spinal flexion — the knee travels while the spine stays long. 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

Goal	Sets × Reps	Rest
Strength	4 sets x 3-6 slow reps per side with a pause at the elbow	2 min
Muscle	3 sets x 9-12 reps per side	60-90 sec
Endurance	2-3 sets x 18-27 reps per side or 40-60 sec continuous alternating	30-45 sec

Level — Beginner

Beginner-to-intermediate — easy to attempt, hard to do with genuinely level hips; the pause at the elbow is the honest version.

Proper form — 5 cues

Hold a high plank with hands under shoulders and feet at hip width.
Sweep one knee out and forward along the side of your body toward the same-side elbow.
Touch or approach the elbow, pause for a beat, then place the foot back exactly where it started.
Keep both hands heavy in the floor so the shoulders do not rock during the sweep.
Alternate sides with a slow, deliberate rhythm — around two seconds per rep.

Breathing: Exhale as the knee travels to the elbow, inhale as the foot returns to the plank.

The 3 mistakes Maddy corrects most

The hip on the moving side lifts toward the ceiling.. Hiking the hip fakes the knee-to-elbow distance while the obliques do a fraction of the intended work. Fix: Keep the pelvis level and accept that the knee may only reach the ribs at first — the range grows as the obliques strengthen.

The knee travels under the body instead of around the outside.. Cutting underneath turns the movement into a mountain climber and shifts the emphasis away from the side trunk. Fix: Trace a wide arc — think of drawing a half-circle on the floor with the kneecap on its way to the elbow.

Speeding up until the touches become taps of momentum.. Fast, swinging reps rely on the hip flexors' momentum, and the oblique contraction you are chasing never actually happens. Fix: Add a one-second pause at the elbow with a deliberate side-ab squeeze before returning the foot.

Common questions

What muscles do plank knee-to-elbow touches work?

The obliques lead — they contract to pull the knee up and around while also stopping the pelvis from twisting. Underneath that, the rectus abdominis and deep transverse abdominis hold the plank, the hip flexors drive the knee, and the supporting shoulder stabilises extra load each time the base narrows. It is a whole-trunk exercise with a side-body bias.

Knee-to-elbow plank vs mountain climbers — which should I choose?

Choose by goal. Mountain climbers run the knees straight under the body at pace, so they bias conditioning and hip-flexor speed. The knee-to-elbow version sweeps around the outside slowly, biasing oblique strength and control. Many good programs use climbers on conditioning days and knee-to-elbow touches on strength days — they are cousins, not substitutes.

Can beginners do this exercise?

Yes, once a 30-second high plank is comfortable. If the full version wobbles, start with the modified variant from the knees or elevate your hands on a bench, which shortens the lever and steadies the hips. Quality marker: your lower back should not change shape at any point while the knee travels.

Related exercises

Easier: Plank Knee to Elbow Touch (Modified)

Bicycle KicksObliques Bicycle Kicks (Modified)Obliques Cross Knee to Elbow PulseObliques Downward Dog Cross Knee to Elbow TouchObliques Downward Dog Knee to Elbow TouchObliques

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