Sessions Guide
How a Hot Cold Coach session works from start to finish.
Before Your Session
Prepare Your Equipment
Before pressing Start, make sure:
- Your sauna or heat source is up to temperature
- Your cold plunge, ice bath, or cold shower is ready
- You have towels nearby
- You're well-hydrated
- You've eaten lightly (avoid heavy meals within 1 hour)
Pre-Session Safety Checklist
Every session begins with a safety checklist. The app reminds you to confirm you're hydrated, equipment is ready, and you'll listen to your body.
During Your Session
The Timer Interface
The session screen shows:
- Large countdown timer — Easy to read from a distance, even in steam
- Current phase label — Whether you're in a heat or cold phase
- Phase-appropriate colors — Warm gradients during heat, cool gradients during cold
- Progress through rounds — How many phases remain
The interface is designed for wet environments with large touch targets, always-on screen, and high contrast for visibility in steam.
Voice Coaching
The voice coach guides you through the entire session:
- Phase transitions — "Time to move to the cold plunge"
- Breathing techniques — Coached breathing during cold phases to manage cold shock
- Encouragement — Motivational cues throughout difficult phases
- Science facts — Brief insights about what's happening in your body
- Completion — Celebrates your effort when the session ends
You can close your eyes and let the voice guide you. The app is built for hands-free, eyes-closed operation.
Audio in Background
Audio continues playing if you lock your phone, switch apps, or turn off the screen. You'll still hear all voice coaching and phase transition alerts.
Speaker tip: For the best audio experience, use a heat-resistant, waterproof Bluetooth speaker like the Saunny Sauna Bluetooth Speaker. Standard speakers aren't rated for sauna temperatures and may malfunction. A heat-rated speaker lets you leave your phone outside the sauna while hearing every voice cue clearly.
Voice Options
The app includes one standard voice for all users, plus additional premium voices for subscribers.
Ambient Soundscapes
Play calming background sounds during sessions: fire crackle, rain, or flowing water. These play between voice coaching cues to help you relax and stay present.
Session Phases
A typical session alternates between heat and cold phases. A common pattern:
- Heat Phase 1 — Enter sauna/heat source for the prescribed duration
- Cold Phase 1 — Move to cold plunge/shower for the prescribed duration
- Heat Phase 2 (if applicable) — Return to heat
- Cold Phase 2 (if applicable) — Return to cold
- Final Phase — Ends warm or cold depending on your protocol goal
The voice coach tells you exactly when to transition and how long each phase lasts.
After Your Session
Post-Session Summary
When your session ends, you'll see total session duration, time in heat vs. cold, and how this session contributes to your weekly targets.
The Søeberg Principle
Some protocols (Biohacking, Athletic Recovery, Mental Health) end with cold and follow the Søeberg Principle: do not artificially rewarm after your cold phase. Let your body generate its own heat to maximize metabolic benefits including brown fat activation.
Tips for Better Sessions
- Don't fight the cold — Relax into it. The breathing techniques help enormously.
- Stay consistent — Regular sessions (3–4x/week) produce better results than occasional long ones.
- Trust Week 1 — The conservative start is intentional.
- End when you need to — If you feel dizzy, nauseous, or unwell, exit immediately.
- Hydrate after — Drink water or electrolytes after every session.