Training

Interval Designer

Design fully custom interval sessions with your own rep distances, target paces, and rest periods. For runners who want complete control over their speed work.

3–5 minute efforts at 5K race effort. Increases aerobic capacity ceiling.

Running 20–50 km/week

If entered, specific target paces are shown for each interval type.

Track your intervals precisely

A GPS watch with interval workout programming helps you hit exact targets for every rep.

Garmin Forerunner 265

Program custom interval workouts directly on the watch. Pace alerts and auto-lap keep you honest on every rep.

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Garmin Forerunner 255

Structured workout support with pace targets and rest timers. Sync workouts from Garmin Connect.

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Nike Pegasus

Responsive enough for intervals, cushioned enough for the warm-up. A versatile trainer for speed sessions.

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How it works

Enter your desired interval distances, target paces, and rest durations. The designer calculates your total workout volume, time-in-zone estimates, and session training load.

Frequently asked questions

What is the difference between the Interval Generator and Interval Designer?

The Interval Generator creates complete sessions from your race pace and fitness level automatically. The Interval Designer gives you full manual control — choose your own distances, paces, and rest periods for maximum customisation.

Interval Designer — Custom Running Interval Workouts | RunReps