@pond-ts/fit

Fitness & activity analytics on pond-ts.

Turn raw activity streams (GPS, power, heart rate, cadence, …) into a typed, immutable activity model with unit-safe quantities and the analytics you'd expect — splits, power (NP / IF / TSS / curve), zones, elevation, best efforts — behind a small Activity / Section façade.

npm install @pond-ts/fit pond-ts

pond-ts is a peer dependency.

Quick start

import { Activity, Distance } from '@pond-ts/fit';

// `imported` is an ImportedActivity — your raw streams (time, lat/lon, power, hr, …)
const activity = Activity.fromStreams(imported);

activity.summary(); // { distance, duration, elevation, avg/max metrics, … }
activity.splits(Distance.km(1)); // per-kilometre Section[]
activity.power(260); // PowerSummary at FTP 260 W — NP, IF, TSS, curve, zones

Attach an athlete Profile for zone-aware, type-safe analytics — the ProfiledActivity knows the athlete, so power/zone calls need no thresholds passed in:

import { Profile } from '@pond-ts/fit';

const profiled = activity.usingProfile(
  Profile.of({ ftpWatts: 260, weightKg: 72 }),
);
profiled.power(); // zone-aware — FTP comes from the profile
profiled.splits(Distance.km(1)); // ProfiledSection[] — slices carry the profile through

Quantities are unit-safe and format themselves:

import { Speed } from '@pond-ts/fit';

Speed.mps(5.5).format('imperial'); // "12.3 mph"

What's in the box

• Façade — Activity / Section: load once, then ask for summary / splits / laps / ranges.
• Quantities — Distance / Speed / Pace / Power / HeartRate / Cadence / … with unit conversions and .format().
• Analytics — geo (distance, elevation, best efforts), power (NP / IF / TSS / curve), and zone distributions.
• Profiles — Profile + usingProfile() → type-safe ProfiledActivity / ProfiledSection.

Documentation

Guides and the full API live at https://pjm17971.github.io/pond-ts/. Source and issues: github.com/pjm17971/pond-ts.

License

MIT