Frequently asked questions
Compatible trainers, browsers, integrations, and where the numbers in the plan come from.
PeakPacing is a web app that computes the power pacing plan for a triathlon, duathlon or cycling race from the GPX track of the course, the athlete's thresholds and the forecast weather, and rides it on a smart trainer in ERG mode over Bluetooth FTMS. It needs an FTMS-compatible trainer or treadmill and a browser with Web Bluetooth (Chrome, Edge or Opera on desktop and Android); on iPhone, trainer control goes through the native iOS build.
Signing in requires a Google account. Intervals.icu and Strava are optional: they import thresholds and planned workouts, and receive the activity recorded on the trainer.
What is PeakPacing?
PeakPacing is a web app that builds the pacing plan for a triathlon, duathlon or cycling race from the GPX track of the course and the athlete's power thresholds, and lets you rehearse it on a smart trainer before the race. It runs in the browser as a Progressive Web App and integrates with Intervals.icu and Strava.
How is it different from other pacing tools?
The best-known pacing tools, Best Bike Split among them, generate the plan and export it to third-party applications such as Zwift or TrainerRoad to be ridden indoors. PeakPacing rides the plan natively: it controls the smart trainer over Bluetooth FTMS from the same application that generated it, with no export step.
Does PeakPacing work with my smart trainer?
PeakPacing uses the Bluetooth FTMS standard (Fitness Machine Service), supported by most smart trainers and treadmills on the market, and needs no manufacturer driver or software. If your trainer exposes the FTMS service and can be controlled in ERG mode, it works; ANT+-only models, and models with a closed proprietary protocol, do not.
Do I have to install an app?
No. PeakPacing is a Progressive Web App: you open it in a browser and can add it to the home screen on iOS and Android without going through the App Store or Play Store. Native iOS and Android builds, made from the same code, also exist for anyone who prefers an installed app.
Which browsers do I need to control the trainer?
Controlling the trainer from a browser requires Web Bluetooth, available in Chrome, Edge and Opera on desktop and on Android. Safari and Firefox do not implement Web Bluetooth: from there you can generate and read plans, but not drive the trainer.
Does it work on iPhone?
On iPhone the web app works normally for creating and reading plans, but iOS exposes Web Bluetooth to no browser at all, Safari included. To control the trainer from an iPhone you need the native iOS build, which reaches Bluetooth through the system APIs.
Do I need an Intervals.icu or Strava account?
No, both are optional. Intervals.icu is there if you want to import your thresholds and already-planned workouts instead of entering them by hand; Strava and Intervals.icu are there if you want to upload the virtual activity recorded on the trainer. To sign in to PeakPacing a Google account is enough.
How are the power targets calculated?
The pacing engine starts from the gradient of every segment of the GPX track and applies a physical model with frontal area (CdA), rolling resistance (Crr), drivetrain loss and a wind component. Wind is resolved segment by segment by comparing its direction with the GPS bearing of that stretch, so the outbound and return halves of the same course get different targets.
Does PeakPacing also say how much to drink and eat during the race?
Yes: alongside the power plan it computes fluid, sodium and carbohydrate targets per hour. The values start from the estimated race duration and the forecast conditions — temperature and humidity — rather than from a rough guess at your own sweat rate.
Can I upload the trainer session to Strava?
Yes. At the end of a session PeakPacing generates a TCX file of the virtual activity, with power, cadence and heart rate, and uploads it to Intervals.icu and Strava if those accounts are connected. The file can also be downloaded and imported elsewhere by hand.
Which languages is it available in?
The PeakPacing interface is available in Italian and English, and the language is changed in the app settings. Units follow the metric system.
Does PeakPacing plan duathlons too?
Yes. Duathlon is one of the race types in the wizard, and its three legs, run-bike-run, are planned together into a single finish time, transitions included: the two runs get a target pace corrected for the gradient of their own course, and the bike leg gets target watts computed from the GPX track with wind and a physics model. The duathlon pacing page explains how the three legs are computed.
Can I rehearse the race plan on a trainer before race day?
Yes. The plan runs in ERG mode on a smart trainer: resistance follows the plan's targets on its own, so the rehearsal gives the real feel of those watts for that duration, before race day and without exporting the plan to a third-party application. The race rehearsal page covers what a rehearsal tells you and how to set one up.