Yuzool

Outsider Lab

Load

Acute : Chronic

0Acute 7d
0Chronic 28d/wk
0Form

Daily strain

Session strainAcute avgChronic avg

ACWR trend

Sweet spot 0.8 – 1.3

This week

Recent

Periodised plan

Train

Build a plan

Base → Build → Peak → Taper, with a lighter week every fourth week.

Interval timer

Log

Personal bests

Records

PR board

Tap ↗ for a PR card

Streaks

Weekly volume

Progress

1RM calculator

Race-day predictor

Riegel

Enter a recent race or all-out effort. Predictions assume you've trained for the distance, and get rougher the further you stretch them.

Heart-rate zones

Medals

Weekly minutes

Squad

Start a squad challenge

Set a target for this week, send the link, and paste your friends' result codes to fill the leaderboard. No accounts.

About Outsider Lab

Outsider Lab is a training load companion for runners, riders and lifters. Log sessions with duration, RPE, distance, heart-rate zones and lifts, then watch acute vs chronic load, ACWR and form, track PRs, and run squad challenges with friends. Outsider Lab Pro, an optional one-time upgrade, builds periodised plans for 5K, 10K, half marathon, strength or general fitness, runs interval sessions with voice cues and predicts race times.

What is ACWR?

The acute:chronic workload ratio compares your last 7 days of training load with your 28-day average per week. Roughly 0.8 to 1.3 is the sweet spot; above 1.5 means you have ramped up much faster than your body is used to.

How is session load calculated?

Session strain is minutes multiplied by RPE (rating of perceived exertion, 1 to 10), in arbitrary units. Optional heart-rate zone minutes and distance add detail to each session.

Is Outsider Lab free?

Yes. Logging sessions, training load, ACWR and form, PRs, squad challenges, backups and CSV export are free, with no ads and no account. Outsider Lab Pro is an optional one-time upgrade ($3.99) that adds the periodised plan generator, the interval timer with voice cues and the race predictor. A plan you already have stays fully usable.

Do I need an account?

No. Outsider Lab needs no sign-up and stores your sessions only in this browser. Back up to a file or export CSV from Settings.

How do squad challenges work without accounts?

Create a weekly minutes challenge and share the link. Each person shares a short result code, and you paste friends' codes in to fill the leaderboard.

Log session

Sport
RPE
6
Heart-rate zone minutes (optional)
Lifts

Plan options

PR card

Your result code

Send this to your squad. They paste it into their leaderboard.

Settings

Outsider Lab Pro

Data

Stored only in this browser.

How load works

Session strain = minutes × RPE (arbitrary units). Acute load is the last 7 days. Chronic load is the last 28 days averaged per week. The acute:chronic ratio (ACWR) shows how this week compares with what your body is used to: under 0.8 is undertraining, 0.8 to 1.3 is the sweet spot, 1.3 to 1.5 is overreaching and over 1.5 is the danger zone. Form = chronic minus acute.

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Shortcuts

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