The open book stretch isolates thoracic rotation by locking out the lumbar spine and hips. It is a go-to drill for anyone who needs more rotational range — overhead athletes, golfers, desk workers, and anyone preparing for movements that demand a mobile upper back.

Setup

  1. Lie on your side with your hips and knees bent to roughly 90 degrees (fetal position). Stack your knees and place a pillow or foam pad between them.
  2. Extend both arms in front of you at shoulder height, palms together.
  3. Keeping your knees stacked and your bottom arm anchored, slowly sweep your top arm up and over your body in an arc, opening your chest toward the ceiling. Follow your hand with your eyes.
  4. Let your upper back rotate as far as it comfortably goes — ideally until your top shoulder touches or nears the floor behind you. Hold briefly, then return with control.

Coaching Cues

What to feel:

  • A rotational stretch through the mid and upper back
  • The chest opening wide as you reach the end range

Common mistakes:

  • Letting the top knee lift off the bottom knee — this means rotation is coming from the hips, not the thoracic spine
  • Forcing the shoulder to the floor rather than letting the thoracic spine rotate naturally
  • Holding the breath — exhale as you open up

Programming

Parameter Recommendation
Reps 8-12 per side
Sets 2-3
Hold time 2-3 seconds at end range
Frequency Daily
When to do it Warm-up, desk breaks, morning routine

Progressions

  1. Beginner: Reduce the range of motion; just rotate as far as comfortable.
  2. Intermediate: Full range as described with a brief hold at end range.
  3. Advanced: Hold a light dumbbell in the moving hand, or add a 5-second isometric push into the floor at end range before returning.