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In and Out to Leg Raises

This floor combo alternates seated in-and-outs — knees pulling to the chest, legs shooting back out — with straight-leg raises, so the abs switch between knee-drive and long-lever work inside one set. It suits home trainees who want more variety than plain leg raises without losing direct hip-flexion volume. 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

GoalSets × RepsRest
Strength4 × 3–6 (each movement)2–3 min
Muscle3–4 × 9–12 (each movement)60–90 s
Endurance3 × 18–27 (each movement)45–60 s

Rep ranges per Helms 2014 · Schoenfeld 2016.

Level — Beginner

Beginner-friendly, provided the lower back stays quiet through the raise portion.

Proper form — 5 cues

  1. Sit on the mat, lean the torso back slightly, and take light fingertip support beside the hips.
  2. Pull both knees to the chest, then shoot the legs out straight without letting the heels touch down.
  3. After your in-and-out count, lie back and switch to raises — legs straight up toward vertical.
  4. Lower the legs only as far as the lower back can stay pressed toward the floor.
  5. Reset the brace at every transition; the switch between moves is part of the exercise, not a break.

Breathing: Exhale as the legs extend or lower — that is where the brace is tested most.

The 3 mistakes Maddy corrects most

Heels crashing down between reps. Momentum takes over and the abs unload at exactly the hardest point of the movement. Fix: Hover the heels an inch off the mat and pause one beat before the next rep.
Lower back arching during the raise half. The hip flexors tip the pelvis forward and the lumbar spine absorbs the strain. Fix: Stop the descent higher, or keep a soft bend in the knees to shorten the lever.
Blurring the two movements together. Rushed transitions turn two distinct exercises into one momentum-driven wiggle. Fix: Treat each half as its own mini-set: brief pause, brace, then continue.

Common questions

Is this combo suitable for beginners?

Yes — both halves self-scale. Keep the in-and-outs small and the leg raises high, with knees slightly bent, and it stays manageable. The one prerequisite is being able to hold the lower back close to the mat; if it lifts on every rep, train bent-knee raises alone first.

Why combine in-and-outs with leg raises instead of doing them separately?

The combination alternates a short-lever knee drive with a long-lever raise, which lets you accumulate more total ab work before fatigue forces sloppy reps of either one. It also keeps home circuits time-efficient — one floor position, two stimuli, no equipment change.

How many reps should I do?

Start with 6–8 of each movement per round for three rounds, resting about a minute between rounds. Progress by adding a rep per week or by slowing the lowering phase, not by racing through more reps at the cost of back position.

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