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Seated in and Out

Balancing on your sit bones with hands beside or behind you, you draw both knees to your chest and shoot the legs back out without letting the feet touch down. The constant hover keeps the abdominal wall and hip flexors loaded for the entire set, packing a lot of core work into a small floor footprint. Coached by Maddy (NASM-CPT) — these are the exact form cues he gives on every client's first week.

Muscles worked

Abs · rectus abdominis Hip flexors · iliopsoas Obliques Deep core · transverse abdominis

Sets & reps by goal

Goal	Sets × Reps	Rest
Strength	4 sets x 4-6 slow reps with a 2-sec hold extended	90 sec - 2 min
Muscle	3 sets x 9-12 reps	60-90 sec
Endurance	2-3 sets x 18-27 reps	30-45 sec

Level — Beginner

Intermediate — the hover is the price of entry; hands-down and heel-tap versions scale it to beginners.

Proper form — 5 cues

Sit back on the sit bones with knees tucked to the chest and feet hovering.
Lean the torso back slightly and find your balance point before the first rep.
Extend the legs out and lower the torso back a few degrees in one motion.
Pull the knees back to the chest as the torso returns upright.
Keep the feet off the floor from first rep to last, moving like a hinge closing and opening.

Breathing: Exhale as the legs extend and the torso reclines, inhale as the knees pull back in.

The 3 mistakes Maddy corrects most

Feet tap the floor between reps.. Each touch unloads the abs and restarts the set from a rest, which quietly deletes the exercise's defining feature. Fix: Shorten the leg extension until you can keep the hover, and lengthen the reach only as strength grows.

Spine rounds into a slump at the tuck.. Collapsing into a C-shape hands the balancing job to passive structures and makes the lower back the first thing to complain. Fix: Keep the chest proud at the tuck and think 'tall fold', letting the hips do the closing rather than the spine.

Legs extend fully while the torso stays bolt upright.. Without the coordinated lean-back, the movement becomes a leg wiggle and the abs never reach their loaded, lengthened position. Fix: Pair the actions — legs reach as torso reclines, knees return as torso rises — like a drawbridge opening and closing.

Common questions

What muscles do seated in-and-outs work?

The rectus abdominis and deep abdominal wall hold your reclined balance the whole set, while the hip flexors drive the knees in and out. The obliques contribute steadying work every time the legs move. It is best understood as combined ab-plus-hip-flexor training — which is why the fronts of your hips will speak up alongside the burn in your midsection.

Are in-and-outs suitable for beginners?

With a modification, yes. The full hovering version demands a level of balance and ab strength most beginners have not built. Start with fingertips resting on the floor behind you and a small leg extension, or allow gentle heel taps for the first weeks. Progress by lifting the hands and lengthening the reach as the hover becomes sustainable.

Why does my lower back hurt during in-and-outs?

The usual culprit is extending the legs further than your abs can counterweight, which drags the spine into an arch at the open position. Shorten the extension, keep the chest tall, and end sets before the shakes turn into slumping. If discomfort continues even at short range, build up first with seated alternate leg raises and dead-bug variations.

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