Anti-movement beats crunching

The abdominal wall’s main job is preventing unwanted movement of the spine and pelvis, not producing flexion. The reformer is unusually good at training that because the moving carriage constantly threatens to displace you.

In long stretch, the carriage is trying to slide away and take your pelvis with it. Holding a straight line against that is a far more demanding core exercise than a hundred crunches, and it transfers to real movement.

The sequence worth doing

These progress from most to least supported. Move on only when the previous one is genuinely controlled.

  • Coordination — 2 springs, teaches breath and limb control against a moving base
  • Knee stretches round back — 2 springs, deep abdominal work with a supported spine
  • Long stretch — 2 springs, anti-extension in a plank position
  • Down stretch — 2 springs, adds spinal extension control
  • Short spine — 2 springs, articulation under load
  • Teaser on the carriage — 1 spring, the integration test

The mistake that removes the benefit

Gripping the hip flexors. In any exercise where the legs are loaded and the spine is meant to stay stable, it is easy to let the hip flexors take over and the deep abdominals disengage.

The tell is a lower back that lifts away from the carriage. If that happens, reduce range before reducing spring — most people can hold the position correctly through a smaller range long before they can through a full one.