Short Box Series

A classical Reformer series performed sitting on the box. Includes round back, flat back, side-to-side, twist, and tree. Develops abdominal strength and spinal mobility.

1 min
Exhale to go back, inhale to return

1Setup

Sit on the short box placed over the carriage. Feet are under the safety strap, hip-width apart. Sit tall with arms crossed over the chest (round back) or reaching overhead (flat back).

2Execution

1. Round Back: Cross arms over chest. Exhale, scoop the abs and round back, rolling the pelvis under. Go as far back as you can with control. Inhale, return to sitting tall. Repeat 5 times. 2. Flat Back: Arms reach overhead by the ears. Hinge the entire spine back as one flat unit. Only go as far as your abs can control. Return to upright. Repeat 5 times. 3. Side-to-Side: Arms overhead. Lift tall, then reach directly to the right, lengthening the left side. Return to centre, repeat left. 3-5 each side. 4. Twist and Reach: Arms overhead. Rotate the torso right, then reach on the diagonal. Return to centre. Alternate 3-5 each side. 5. Tree: Extend one leg, hold behind the thigh. Walk hands up the leg to straighten it. Round back holding the leg, then climb back up. 3 times each leg.

Tips for Better Form

  • The strap should feel snug — it's your safety anchor
  • Scoop the abdominals deeply before any backward movement
  • Keep the hips anchored on the box
  • For flat back, think of lengthening the spine, not just leaning back

Watch Demo

Practice with Aria

Get voice-guided instruction for this exercise

Target Areas

Front

Back

Equipment Needed

reformer
box

Master Short Box Series with a Pro

Find certified reformer instructors in your area for personalized guidance.

Related Exercises