Ninety-Ninety Hip Switch

3 × 8/side, rotate knees floor to floor under control, tall spine.

Difficulty 2 of 52.8 METs · Light

Equipment

Mat

Muscle groups worked

Hip flexors
Adductors
Core

What it buys you

Buys rotational range at the hip, which is what lets the pelvis move independently of the spine.

Capacity trained

Mobility. Hip, adductor and thoracic range. Determines which positions are available and comfortable.

Train it · Open Hips Test your limiter

Energy

Modelled kilocalories

Modelled energy cost for Ninety-Ninety Hip Switch at 10, 20, 30 and 45 minutes for both reference bodies
Reference body	10 min	20 min	30 min	45 min
Male reference · 82 kg	40 kcal	80 kcal	121 kcal	181 kcal
Female reference · 68 kg	33 kcal	67 kcal	100 kcal	150 kcal

Energy figures are modelled from standard activity MET values (Ainsworth Compendium, 2011) and the ACSM equation, not measured on you. They scale linearly with your own body mass, so a body 10% heavier burns about 10% more at the same intensity.

kcal = METs × 3.5 × bodyweight(kg) ÷ 200 × minutes (ACSM)

Load is effort, not pain. If a movement hurts rather than works, stop and see a clinician. Lifting another person is strength training with a person-shaped load — build the pattern unloaded first.

Cross-reference

Positions this workout helps · 51

It serves Seated, Side-Lying, Supine Base and Seated Astride. Every position in those families is listed below, hardest first.

Honest framing

Training makes a posture available and sustainable. It is capability work, not a treatment for anything, and no single session changes a number. Consistency over eight weeks does.