From your season plan to the beeps on your watch Plan and analyse your training with software built for coaches, clubs and athletes

Slek, the training planning and tracking software

Slek is planning, tracking and analysis software built for endurance sports: running, trail running, triathlon, cycling, swimming, athletics… It is made for coaches, clubs and athletes, and it serves the coach who follows thirty athletes just as well as the person who trains alone. It is a web app (PWA): it installs on your phone straight from your browser, with no Google Play and no App Store, and it is always up to date.

From the season plan to the workout analysis

Everything starts with the season: macrocycles, mesocycles, microcycles, goals and races go into a spreadsheet view that you adjust as the weeks go by. Each week is then planned workout by workout, with the athlete’s availability in front of you. A workout can be guided: you build it in a graphical editor by laying out blocks (warm-up, effort, recovery, repeated block, cool-down) with targets expressed as a percentage of VO2max speed, of maximum heart rate, of FTP, in zones or in RPE, and Slek turns that into a pace or a wattage for each athlete before sending it to their watch.

The loop closes on the way back: the completed activity uploads on its own, sits next to what was planned, and feeds the analysis, with training load using Foster or TRIMP, acute / chronic ratio (ACWR) and its recommended range, monotony index, time spent in each zone, how the volume moves. On top of that come the subjective data that some tools leave out: how the workout felt, form on waking, perceived effort, regular check-ins. The numbers and the lived experience, in the same place.

Free for coaches and for clubs

Coaching is free in Slek, and that is a deliberate choice: a Free account is all a coach needs to work with an athlete, however many athletes they follow. It is the athlete who takes out the Premium subscription. A club has no licence and no plan to pay for, and the same athlete can be followed by several coaches at once (club, school sports section, regional group), each of them seeing the load added by the others. The details are on the pricing page.

Sharing a workout without sharing your data

Slek also has training squads: one where a few coaches plan workouts and offer them to every member, without ever reading anyone’s training data. A club sends Tuesday evening’s workout to its members that way, and three colleagues can sort out a lunchtime run between them, with nobody having to open their training diary to the others. Each workout arrives as an invitation that you accept or decline, and a single Premium subscription is enough to keep the squad running.

Plugging your own AI assistant into your data

Slek ships an AI-based coaching assistant, billed as you go from prepaid credit, and also exposes an MCP connector (Model Context Protocol). If you already pay for Claude or Mistral, you plug it into your Slek account and ask about your workouts, your load and your plan straight from your assistant: your own requests foot the bill, at no extra cost on the Slek side. As things stand, ChatGPT does not allow this kind of connection. Setting up the connector is documented step by step.

Works with your watch and your bike computer

Slek picks up the activities recorded on Garmin, Suunto, Coros, Polar, Strava, Wahoo and Hammerhead on its own: you change brand whenever you want, your history stays yours, and both import and export of your data are included from the free plan onwards. In the other direction, guided workouts are sent to Garmin, Suunto and Coros watches and to Wahoo and Hammerhead Karoo bike computers, so the athlete is guided step by step during the workout.