Fortify
Muscular endurance
Slow, controlled, deliberately flowing movement. Resilience that carries off the reformer and into life.
The method
One method. Three principles.
ONYX is heated reformer pilates. Every class runs 45 minutes on a reformer in a room at 90°F, heated by infrared panels rather than forced air. The work is organised around three principles — Fortify, Sculpt and Burn — and the studio rotates through them month by month.
How heated reformer pilates is different
Conventional reformer pilates trains strength and control on a spring-loaded carriage at room temperature. ONYX runs the same apparatus in a room heated to 90°F using infrared panels. The difference is not the sweat. It is what the heat does to the tissue you are training.
Infrared penetrates deep into muscle tissue rather than warming the air around you. Circulation rises. Warm-up accelerates. Oxygen reaches working muscles faster. The result is a deeper range of motion, greater muscular activation, and faster recovery between sessions.
It is not hot yoga, and it is not a mat class. There is no flowing sequence held for breath. Every class is resistance work under load on a reformer, programmed to a principle, and opened with a powerhouse warm-up.
The rotation is deliberately not published. Members train what the studio programmes that month, which is how a system produces balanced adaptation instead of letting people repeat their favourite class. The method is a system, not a menu.
The three principles
Each principle trains a different quality, defined by how the movement is loaded and paced. Together they cover endurance, strength and power.
Every class draws on muscle specificity training — different stimulus, different result. Nothing is left to chance. You show up. Principle rotation does the rest. Rotation is not posted. Each principle matters. The method is a system, not a menu.
Sculpt
Muscular strength
Extended holds, targeted pulses, increased load. Time under tension, applied with intent.
Burn
Muscular power + cardio
Hybrid intensity with cardio bursts. Full-spectrum challenge, built on the other two.
Why infrared, not hot air
A conventional heated room warms the air, which then warms you from the outside in. Infrared panels emit radiant heat that passes into muscle tissue directly.
That means the warm-up starts in the muscle rather than on the skin. Members reach working range sooner, hold positions longer, and recover faster.
90°FRoom temperature
45Minutes
3Principles
The classes
Signature classes carry the full method. Targeted and Restorative classes are scheduled off-peak.
Signature
ONYX45
The flagship. 45 minutes cycling Fortify, Sculpt and Burn on a monthly rotation. Full-body, full-method.
ONYX90
The extended signature. More time, more reps, more results. Double the duration.
Targeted
CORE45
Engineered around core strength, stability and control. The method applied to the midline.
UPPER45
Arms, shoulders, chest and back. Method-driven sculpting from the waist up.
LOWER45
Glutes, legs and lower-body power. Method-driven sculpting from the waist down.
Restorative
RECHARGE45
Lower-intensity movement to restore, lengthen and prepare the body for what is next.
Run & Recharge
Seasonal. A two-mile run from the studio, then RECHARGE45. Fridays, both studios.
Two rooms. Same standard.
River North and Wicker Park. Both heated, both running the same rotation.