Progress Tracking, Volume Charts, and Personal Records

Blackterz offers two complementary progress views built entirely from data already captured during normal training sessions. The weekly volume chart gives a macro view of training load over time, while the personal records (PRs) board surfaces the best performance ever logged per exercise. Both are derived from the sesion_series table and require no additional input from the user.

Weekly Volume Chart

The profile page renders a Chart.js 4 bar chart showing total training volume per ISO week for the last 8 weeks. Volume for each week is the sum of peso × repeticiones across all completed sets (completada = 1) in sessions that fall within that week.

Fetch session history

GET /api/sesiones returns the full history. Each session already includes volumen_total_kg — a pre-aggregated sum calculated server-side by the obtenerHistorialUsuario query.

Group by ISO week

The frontend calculates the Monday of each session’s week using:

const fechaLimpia = sesion.fecha.split('T')[0];
const fecha = new Date(fechaLimpia + 'T00:00:00');
const diaSemana = fecha.getDay() || 7; // Sunday becomes 7
const lunes = new Date(fecha);
lunes.setDate(fecha.getDate() - diaSemana + 1);

Sum volume per week

Sessions in the same ISO week accumulate into a single bucket. The result is a map of { 'YYYY-MM-DD': totalKg } keyed by each week’s Monday.

Render the last 8 weeks

The map is sorted chronologically and sliced to the 8 most recent weeks to keep the x-axis readable. A Chart.destroy() call precedes every re-render to prevent memory leaks.

Routine filter

A <select> dropdown above the chart lets users filter volume by routine. Selecting a specific routine re-groups the data to include only sessions linked to that routine. Selecting “Todas las rutinas” restores the aggregate view.

The chart receives the complete history array — not the current page of the paginated table. Pagination only affects the history table rows; the chart always reflects all available data.

Personal Records

GET /api/estadisticas/prs returns the maximum weight ever logged per exercise, considering only sets marked as completed (completada = 1).

curl http://localhost:3000/api/estadisticas/prs \
  -H "Authorization: Bearer <token>"

The model runs a single aggregation query across four joined tables:

SELECT
  e.id              AS ejercicio_id,
  e.nombre          AS ejercicio_nombre,
  MAX(ss.peso)      AS peso_maximo,
  MAX(ss.repeticiones) AS reps_maximas,
  COUNT(DISTINCT ss.sesion_ejercicio_id) AS veces_entrenado,
  COUNT(ss.id)      AS total_series_completadas
FROM sesiones_entrenamiento se
JOIN sesion_ejercicios sej ON sej.sesion_id = se.id
JOIN sesion_series ss     ON ss.sesion_ejercicio_id = sej.id
JOIN ejercicios e        ON e.id = sej.ejercicio_id
WHERE se.usuario_id = ? AND ss.completada = 1
GROUP BY e.id, e.nombre
ORDER BY peso_maximo DESC

Sample PR response

{
  "status": "ok",
  "data": [
    {
      "ejercicio_id": 8,
      "ejercicio_nombre": "Peso muerto",
      "peso_maximo": 120,
      "reps_maximas": 5,
      "veces_entrenado": 14,
      "total_series_completadas": 42
    },
    {
      "ejercicio_id": 4,
      "ejercicio_nombre": "Press de banca",
      "peso_maximo": 100,
      "reps_maximas": 8,
      "veces_entrenado": 22,
      "total_series_completadas": 66
    }
  ]
}

PR response fields

ejercicio_id

number

The exercise’s primary key.

ejercicio_nombre

string

The exercise’s Spanish display name.

peso_maximo

number

Highest weight (kg) ever logged in a completed set for this exercise.

reps_maximas

number

Highest repetition count ever logged in a completed set.

veces_entrenado

number

Number of distinct sessions in which this exercise appeared.

total_series_completadas

number

Total count of completed sets ever logged for this exercise.

If the authenticated user has no completed training sessions, the endpoint returns an empty array [] — never an error.

Session History Table

The profile view includes a paginated history table showing the 10 most recent sessions per page.

Table columns
Pagination

Column	Source
Date	`sesiones_entrenamiento.fecha` formatted as `"15 de junio, 2026"`
Routine	`rutinas.nombre` via `LEFT JOIN`
Volume	`volumen_total_kg` (pre-aggregated)
Sets	`total_series` (completed sets count)
Duration	`duracion_minutos`
Detail link	Navigates to session detail view

The frontend caches the full history array in historialDatosCompletos. Page changes re-slice the cache — no additional API calls are made.

const HISTORIAL_POR_PAGINA = 10;
let historialPaginaActual = 1;

function renderTablaHistorial(pagina) {
  const inicio = (pagina - 1) * HISTORIAL_POR_PAGINA;
  const fin = inicio + HISTORIAL_POR_PAGINA;
  const paginaData = historialDatosCompletos.slice(inicio, fin);
  // render rows...
}

If the total session count is ≤ 10, pagination controls are hidden entirely.

Progressive Overload

GET /api/sesiones/ultima/:rutina_id is the bridge between the history system and the active training flow. It returns the most recent session for a routine with sets grouped by exercise, enabling the frontend to show each set’s previous values as grey hints.

curl http://localhost:3000/api/sesiones/ultima/3 \
  -H "Authorization: Bearer <token>"

{
  "status": "ok",
  "data": {
    "sesionId": 17,
    "ejercicios": {
      "4": [
        { "peso": "60.00", "repeticiones": 10 },
        { "peso": "62.50", "repeticiones": 10 }
      ]
    }
  }
}

The workflow:

Load the routine

GET /api/rutinas/:id provides planned sets and reps.

Fetch the last session

GET /api/sesiones/ultima/:rutina_id retrieves actual weights and reps from the previous workout.

Inject hint values

inyectarAnteriorEnCards() adds a <span class="anterior-valor"> to each set row showing the previous values (e.g. 60kg × 10). These hints are purely visual — they do not pre-fill the inputs, encouraging the user to consciously decide whether to match or exceed last session.

Data Source

All statistics — weekly volume, personal records, session history totals — are derived exclusively from the sesion_series table. The relevant columns are:

Column	Type	Description
`numero_serie`	INT	Set number within the exercise (1-indexed)
`repeticiones`	INT	Reps performed
`peso`	DECIMAL	Weight in kilograms
`completada`	BOOLEAN	Whether the user checked this set as done

Only rows where completada = 1 contribute to PRs and volumen_total_kg calculations. Unchecked sets are saved to the database but excluded from all statistics.

Weights are stored as logged by the user. There is no unit conversion — the app assumes all values are in kilograms. If a user logs bodyweight exercises with peso = 0, those sets appear in history but contribute zero volume and zero to PR calculations.

API Reference — Statistics

View the full schema for GET /api/estadisticas/prs.

API Reference — Sessions

View the full schema for GET /api/sesiones and GET /api/sesiones/ultima/:rutina_id.

Get Started

Core Features

Architecture

Progress Tracking, Volume Charts, and Personal Records

Weekly Volume Chart

Routine filter

Personal Records

Sample PR response

PR response fields

Session History Table

Progressive Overload

Data Source

API Reference — Statistics

API Reference — Sessions

Build docs developers (and LLMs) love

Get Started

Core Features

Architecture

Documentation Index

​Weekly Volume Chart

​Routine filter

​Personal Records

​Sample PR response

​PR response fields

​Session History Table

​Progressive Overload

​Data Source

API Reference — Statistics

API Reference — Sessions

Build docs developers (and LLMs) love

Weekly Volume Chart

Routine filter

Personal Records

Sample PR response

PR response fields

Session History Table

Progressive Overload

Data Source