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Triathlon · HRV

HRV-guided triathlon training
with the Unbroken Protocol.

Let your body set the day. Unbroken reads your heart rate variability, sleep and training load each morning and turns them into one decision: push, activate, or recover. You train hard when you can absorb it, and back off when you cannot, so the work actually becomes fitness.

Home/The Method/HRV-guided triathlon training
An endurance athlete training at dusk, guided by readiness
The idea

Train by readiness, not by the calendar

Heart rate variability is the variation in time between heartbeats. A trend relative to your own baseline can add useful recovery context, but a single value is noisy and does not identify the cause of a change. HRV-guided training reads that trend alongside sleep, symptoms, recent load and the planned session.

For the full science of what HRV measures and how to read your morning number, see the explainer: HRV training for triathletes. This page is about how Unbroken turns that signal into a system you can actually train by.

The system

How we coach by HRV

Each morning the Unbroken Protocol app brings four inputs into the Protocol Score: HRV trend, sleep, recent training load and a short check-in. The score is decision support, not a diagnosis or an instruction to ignore symptoms.

No single metric decides the session alone. Read the score with the purpose of the training block, how the athlete feels and whether movement quality or illness changes the risk of proceeding.

Unbroken Triathlon Club swimmers training at the pool
Swim, bike and run intensity set by your readiness, not a plan written three weeks ago.
The discipline

Read the trend, not the single number

The most common mistake with HRV is over-reacting to one reading. A single morning value is noisy. Sleep position, a late meal, alcohol, a stressful day, even when you took the reading, all move it. What matters is the trend across days and weeks against your own baseline, and the context of your recent load.

A one-day dip can follow training, poor sleep, alcohol, illness, travel or measurement variation. A sustained change deserves context and a review of the planned load; it does not predict an injury or identify a medical cause. The foundations are on the recovery page.

The payoff

Where HRV guidance helps—and where it does not

A fixed plan cannot know how the athlete slept or how the previous sessions landed. HRV can prompt a useful review when the current response differs from the assumption in the plan.

It cannot diagnose illness, guarantee adaptation or replace symptoms, conversation and coaching judgement. The practical value is a more informed decision about whether to keep, modify or postpone a demanding session.

Start

Train by your readiness

See the app page and current App Store listing for supported data sources and platform availability. Coaching and the London club are separate support options and are confirmed after an enquiry.

Questions

HRV-guided training, answered

What is HRV-guided triathlon training?
It uses your HRV trend as one source of recovery context alongside sleep, symptoms, recent training load and the purpose of the planned session. One reading should not decide the day alone.
How do I use HRV to decide whether to train hard?
Compare the trend with your own baseline, then review sleep, symptoms, recent load and session purpose. A meaningful change is a reason to review the plan, not an automatic instruction to train hard or rest.
Is one morning HRV reading enough?
No. A single value is noisy. Trends across consistent measurements are more useful, and still need context from sleep, symptoms, recent load and how the athlete feels.
What devices can I use?
See the Unbroken app page and current App Store listing for supported data sources and platform availability. Compatibility can change, so those current product sources take precedence.
How do I start?
Use the iOS app for self-directed training context, or submit a coaching enquiry if you need individual programming and direct feedback. Coaching and club access are separate services.

Let your body set the day

Place HRV trends beside sleep, athlete feedback and training load before deciding how the day should run.

Weekday email

One piece like this, every weekday at half six.

In your inbox before the day starts. Nothing to download, nothing to buy, and you can stop them any time and keep the Sunday Brief.

One confirmation email, and that is the last step.

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