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Corten U · Contrast Education

Heat. Cold.
And what happens in between.

Contrast therapy is not a spa treatment. It is deliberate, dosed exposure — heat that trains the cardiovascular system, cold that trains the nervous system, and breath, sound and stillness that turn exposure into practice. Here's how each layer works, and how they stack.

SaunaIce BathContrastSoundBreathworkMeditation

80–100°C

Sauna air

15–20 minutes per round

3–10°C

Plunge water

1–3 minutes per round

11 min

Cold per week

Spread over 2–4 sessions

Explore the modalities

Six layers, one session

Select any layer to see what it does, what the research supports, and how it should feel in the room.

Hot therapy

Heat as training stimulus

Deliberate heat exposure raises core temperature roughly 1–2°C, driving a hormetic stress response — a small, controlled stressor the body adapts to and grows stronger from.

Conditions

80–100°C dry · 15–25% humidity

Typical dose

15–20 min · 2–4 rounds · 3–5x per week

Heart rate climbs to 100–150 bpm and blood vessels dilate, producing a load pattern that resembles moderate aerobic exercise. Regular frequent sauna use is associated in long-running Finnish cohort research with markedly lower cardiovascular mortality.

Heat triggers HSP70/HSP90 expression — molecular chaperones that repair misfolded proteins, protect muscle tissue and support cellular resilience for days after the session.

Increased blood flow to muscle beds clears metabolites and reduces delayed onset soreness after hard training days.

The post-sauna core temperature drop mimics the body's natural pre-sleep cooling curve. Endorphin and dynorphin release explains the calm, glassy afterglow.

What it feels like

Heavy warmthDeep exhaleSkin flushMental quiet

Practise safely

Hydrate before and after. Exit if lightheaded. Avoid alcohol. Pregnancy and cardiac conditions require medical clearance.

The full stack

  • HeatLoads the cardiovascular system
  • ColdTrains the stress response
  • BreathGives you the controls
  • SoundSets the pacing of the room
  • StillnessConsolidates the adaptation

How you can practise

Self Led or instructor-led

The contrast studio runs two ways: Self Led on your own clock, or a coached class. Instructor-led sessions come in three forms — one for the mind, one for the body, and one that puts the two together.

Self Led

Self Led

Self

60 min · your pace

A 60-minute window on the open floor. Sauna, plunge and rest are yours to cycle through on your own clock — do as many self-led rounds as you like, and leave whenever you are ready. Posted protocols and an attendant on deck keep it safe and simple.

  • 60-minute open-floor window
  • As many self-led rounds as you want
  • Beginner, standard and athlete protocol cards
  • Ambient soundscape, no coaching
  • Attendant on the floor for safety

Best forMembers who know their dose and want autonomy without a fixed class time.

Instructor-led · Mind

Still

Mind

60 min

Contrast as a nervous-system practice. Longer, gentler heat, short controlled cold, and a lead who works the breath, the sound and the silence between rounds.

  • Led breathwork before and after each plunge
  • Live or scored sound bath through the heat rounds
  • Extended integration stillness to close
  • Lower cold dose, higher attention

Best forStress load, sleep, and anyone who finds the cold mentally loud.

Instructor-led · Body

Forge

Body

60 min

Stretching in the sauna — heat as cardiovascular load, cold as a deep reset, with clean work-to-rest structure.

  • Coached rounds
  • Higher sauna dose, full-shoulder cold immersion
  • Mobility and movement in the transitions
  • Recovery-timing direction around training days

Best forAthletes and Gym 1 / Reformer members chasing recovery and capacity.

Instructor-led · Mind + Body

Temper

Mind + Body

60 min

The signature. Like steel shaped by heat and cold in sequence, the practice builds resilience over time. Athletic rounds front-loaded, breath and stillness on the back half, one arc from effort to calm.

  • Three coached heat/cold rounds, descending intensity
  • Breath protocol taught, then practised under cold
  • Sound-scored final round
  • Long horizontal integration to finish

Best forFirst-timers who want the full story, and members making it a weekly ritual.

Led contrast

Led Contrast

A coached round of contrast run by an instructor — the room moves together, the clock is held for you, and the soundtrack carries the session.

Goal

Coached group experience

Duration

60 min

Ending

Finish cold

  1. Arrival & intention5 min
  2. Breath primer5 min
  3. Sauna round one14 min
  4. Plunge2 min
  5. Sauna round two14 min
  6. Plunge2 min
  7. Sound integration10 min

Self-led protocols

Sessions you can run yourself

On the open floor you set the clock. Pick a protocol below to see exactly how the session is built — round by round, with the timings we recommend.

Goal

Learn the format without overreaching

Duration

45 min

Ending

Finish warm

  1. Breath primer3 min
  2. Sauna10 min
  3. Cool down3 min
  4. Plunge1 min
  5. Sauna12 min
  6. Plunge1 min
  7. Integration8 min
Session soundtrackSoul Expansion — Audio JourneysLed breathwork, sound baths and integration meditations to score the session. Members sign in to listen.

Ready

—

Try it now

Box breath, extended exhale

In for four, hold four, out for six, hold two. The long exhale is the vagal brake — this is the pattern to run on the edge of the plunge, before your first toe touches water.

0 cycles complete

Common questions

Before your first round

Colder is not better. Anything between 3°C and 10°C is a real stimulus. What matters is time under control — staying calm for 90 seconds at 8°C beats panicking for 20 seconds at 2°C.

Finish cold when you want alertness for the rest of the day. Finish warm when the goal is sleep, down-regulation or a session late in the evening.

Two to four sessions a week is where most of the research benefit sits. Consistency over months outperforms heroics in a single week.

Heat, yes. If maximum muscle growth is the goal, keep the ice bath at least four hours away from a heavy strength session. Around competition or heavy volume, plunge freely.

Sit near the door, keep rounds short, and let the breath lead. Most anxiety in the sauna is heat plus a fast breathing pattern — slow the exhale and it usually resolves.

Anyone pregnant, or with uncontrolled blood pressure, cardiac arrhythmia, epilepsy, Raynaud's or recent surgery should get medical clearance first. Keep alcohol out of the mix.

A bathing suit is perfect. A light cover-up is optional for moving between the sauna and plunge. We recommend bringing a dry change of clothes for after.

A water bottle is the one must-have. Hydration before, during and after the session makes the experience safer and more enjoyable. Towels and sandals are provided.

The Corten Contrast Experience

Anyone can sit in a hot room. Practice is what changes people.

Coached rounds, scored sound, and an ending you actually sit still for — that's the difference between a plunge and a practice.

Educational information only, not medical advice. If you are pregnant or manage a cardiovascular, neurological or blood pressure condition, speak with your physician before beginning heat or cold exposure.

On the team? This material lives in the Training Portal too