Physiology engine

The motor catches drift
before you do.

Not a chat bot — a decision engine that turns wearable signals into physiological models. When HRV, pace, or sleep drifts, it updates the plan and writes the physiological rationale.

Garmin
Strava
WHOOP
Oura
+14 integrations
D
driftline · WhatsApp
HRV has been low for 3 days. I cancelled today's tempo and put in 35 min easy instead.07:04
Makes sense — legs still feel heavy.07:06
Garmin load says the same. I moved Thursday forward so race week stays calm.07:07
Scientific foundation

Not an AI coach — a physiology engine.

A six-stage methodology: signal collection, individual normalization, drift detection, literature validation, simulation, and transparent output. Supported by real case studies, 5 reference publications, and a 847+ source literature layer.

What it reads

Your body is already talking. Nothing is listening.

Driftline continuously monitors three signals and rewrites the plan the moment one starts to drift — before you notice.

HRV curve

If overnight recovery falls for three days in a row, the next day's session is automatically eased.

Pace drift

If easy-run pace slips 10–15 s/km over weeks, it catches that before you do.

Load ratio

Acute:chronic workload ratio (ACWR) is one of three signals — never the sole decision. Volume is pulled back only when it co-anomalies with HRV and pace drift.

How it works

Connect, introduce yourself, keep training.

01 — CONNECT

Link your stack

OAuth-connect Garmin, Strava, WHOOP, Oura, and more in about two minutes.

02 — LEARN

Let the coach learn you

Share goals, constraints, and history freely — no card required.

03 — ADAPT

Let the plan rewrite itself

When you skip, sleep poorly, or life intervenes, the 14-day plan updates automatically.

This week
MONTUEWEDTHUFRISATSUN
Decision chain · live example
SignalHRV ↓ 3 daysRMSSD −18% · below individual baseline(≥3 consecutive nights RMSSD < 30-day mean − 1.2 SD or Δ% < −12%)
AnalysisRecovery driftAcute load + low HRV · risk threshold crossed(RMSSD 1.5 SD below individual 30-day mean; ACWR > 1.15)
ActionIntensity −15%Tempo → 35 min Z2 · Thursday moved earlier(composite risk ≥ 0.70 → intensity −10–20%; today −15%)

The panel your coach sees every day.

Load, recovery, and readiness — the plan changes the moment your data does. Tomorrow's session is ready on your watch.

D
driftline · sample messages
HRV has dropped for 3 days.We recommend reducing today's intensity by 15%.07:04
OK, switching to an easy run.07:06
Plan updated — 35 min Z2. Garmin load points the same way.07:07
What changes in training

For athletes who take it seriously.

It caught my easy paces drifting 15 s/km over two weeks. Without it, weeks would have slipped by.

It saw HRV falling three days in a row and delayed my intervals. Turns out I was getting sick.

I have a coach, but they can't read daily data that often. Driftline fills the gap.

Training Goals

Whatever the goal, the plan is yours.

Driftline learns your training goal and rewrites the plan daily from HRV, pace, and sleep data.

See all goals →

Compare

How is it different?

It does not wait for you to open a dashboard — when HRV, pace, or sleep drifts, it updates the plan and messages you on WhatsApp.

All 12 comparisons →

Pricing

One plan, 7 days free.

COACHING
€10 + VAT / month

Discounted annual plans coming soon

  • It writes first after every session and every hard night.
  • HRV, pace, power, sleep — reads your real data in real time.
  • Garmin, Strava, WHOOP, Oura, and 14 more integrations.
  • When you skip or sleep poorly, it rewrites the plan.
  • Tomorrow's session appears on your watch, ready on time.
Activate AI coach7 days free · no card required
Early access

Try 7 days free.

No card required. The coach asks a few questions to learn you; we'll notify you first when it opens.

FAQ

Common questions.

Why not just use ChatGPT?

ChatGPT cannot see your data, message you first, or manage a plan. Driftline reads your real numbers via integrations, messages first when drift appears, and rewrites the 14-day plan accordingly.

AI coach or physiology engine?

Driftline is not a chat bot. Decisions come from physiological models; the LLM only explains the rationale. The six-stage methodology — signal, normalization, drift, literature, simulation, output — is detailed on the research portal.

Is it evidence-based?

Yes. Established principles such as 80/20, VDOT, periodization, and tapering are applied to your individual signals. Every intervention is cross-checked against a 847+ source literature pool and 5 direct reference papers.

Does it replace a human coach?

No — it complements one. Race strategy and motivation still need a human coach; Driftline owns the daily data monitoring most coaches lack time for.

Is my data safe?

Connections are read-only, data is stored encrypted, and nothing is sold or used for model training. You can delete your account anytime.