How to Complete Your Calibration Session (Baseline IELT)
Calibration is the mandatory first session that measures your baseline IELT and unlocks the AI trainer and duo mode. Here is exactly what happens and why it matters.
Written by the Hold The Beat education team · Last reviewed August 19, 2026
Calibration is a short guided session that measures your starting point: the time from the first beat until your first pause, which is your baseline IELT. It is required once, takes a few minutes, and unlocks the adaptive trainer — without it the AI has no reference to build your sessions from.
Why calibration is mandatory
The AI trainer designs every session around your current threshold, and weekly goals are compared against your baseline so progress is always relative to you. Skipping calibration would mean guessing, so the app blocks the AI and duo modes until you complete it. This is a one-time requirement: after it, the app knows where you start.
Solo or partner
Before starting, calibration asks you to pick a mode:
- Solo — you control the pauses yourself. Recommended for almost everyone.
- Partner (Duo) — your partner controls the pauses through the app. Choose this only if you already train together; the duo guide explains the setup.
What happens during the session
The calibration uses the same flow as a normal session:
- Warm-up. Reach 70–80% arousal following the guidance on screen.
- Active phase. Follow the beat. When arousal approaches the point of no return, press Pause — the app records this as your first stop.
- Pause and resume. Rest at least 15 seconds (recovery cooldown) and continue when you feel ready.
- Feedback. Answer the short form honestly; your answers complete the baseline profile.
What it unlocks
- Adapted Start-Stop (AI Trainer) — solo adaptive sessions.
- Trainer Duo — partnered sessions.
Can you redo it?
Yes. The warm-up screen includes a Recalibrate baseline option. Redo it after a long break, after a big change in performance, or whenever you feel your baseline no longer reflects reality. It is the same short session as the first time.
Tips
- Don't overthink it. The number is data, not a grade. It only exists so the AI can adapt to you.
- Be honest in the feedback. A flattering baseline leads to sessions that are too hard or too easy.
- Choose privacy. Do it in a place where you will not be interrupted.
What to do next
Once calibrated, read Your First AI Start-Stop Session to know what happens inside the four stages, or go back to the complete trainer guide.
Sources
Last reviewed: 2026-08-14 · Written by the Hold The Beat education team. Educational content, not medical advice.