In And Out

Beginner
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Bodyweight core exercise targeting the lower abs and hip flexors to build endurance and stability; performed lying down with leg lifts and knee tucks.

About Exercise

Equipment

Difficulty

2/5 • Beginner

Primary Muscle Groups

Abs, Hip Flexors

Secondary Muscles

Obliques

Popularity Score

6

Goals

Endurance
Stability
Conditioning

Training Style

Calisthenics

Setup Requirements

Requires Rack

No

Requires Bench

No

Requires Spotter

No

Space Needed

Small

Noise Level

Low

Muscle Breakdown

Abs

10/10

Rectus Abdominis

Hip Flexors

8/10

Iliopsoas

Obliques

4/10
Programming

Typical Rep Range

10-25 reps

Rest Between Sets

30-60 seconds

How to Perform

Lie on your back with legs extended and arms at sides, palms down for stability.

  1. Lift legs to 90 degrees with knees straight.
  2. Bend knees and pull them toward chest, rounding lower back slightly.
  3. Extend legs straight out low, hovering above ground.
  4. Pull knees back in toward chest.
  5. Repeat for reps, keeping lower back pressed down.

Coaching Tips

Form Cues

  • Keep lower back flat
  • Engage core throughout
  • Move legs slowly
  • Control the extension
  • Breathe steadily

Breathing

Inhale as you extend legs out; exhale as you pull knees in and brace core.

Tempo

2-0-2

Range of Motion

Legs from 90-degree lift to hovering 6 inches off ground; avoid arching lower back.

Safety

Safety Notes

  • Stop if lower back pain occurs
  • Modify by bending knees if hamstrings tight
  • Avoid if recent abdominal surgery

Spotting

No spotting needed; perform on padded surface for comfort.

Common Mistakes

  • Arching lower back
  • Swinging legs wildly
  • Letting feet touch ground
  • Using momentum over control
  • Neck straining

When to Avoid

  • Lower back injury
  • Hernia
  • Recent abdominal surgery

Flexibility Needed

  • Hip flexion mobility
  • Hamstring flexibility

Build Up First

  • Basic core awareness

Also known as

In-Out Leg Raises, Alternating Knee Tucks

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