Build workouts

Resolve exercises, build a draft session, read it back, and publish separately.

buildSession() creates one session inside a program, saves its blocks and exercises, and can optionally publish it. The safer workflow is draft first, inspect second, publish last.

import { buildSession } from "@trainheroic-unofficial/js";

const { match } = await library.resolve("Back Squat");
if (!match) throw new Error("Choose one exercise before building");
if (match.units[0] !== "reps" || match.units[1] !== "lb") {
  throw new Error("Choose an exercise with reps and pounds as its fixed units");
}

const { pwId, workoutId } = await buildSession(client, {
  programId: 12345,
  index: library,
  date: [2026, 8, 17], // [year, month, day], with a 1-based month
  instruction: "Warm up first.",
  blocks: [
    {
      title: "Strength",
      exercises: [
        {
          id: match.id,
          sets: 5,
          reps: 5,
          primaryUnit: "reps",
          weight: 225,
          secondaryUnit: "lb",
          rpe: 8,
        },
      ],
    },
  ],
  publish: false,
});

reps and weight accept one scalar for every set or a per-set array such as reps: [5, 5, 3]. State primaryUnit for the reps slot and secondaryUnit for the weight slot. buildSession checks both against the exercise library before writing.

Session handles

• pwId identifies the session’s placement in the program. Read, publish, unpublish, copy, and remove operations use it.
• workoutId identifies the underlying workout record.