About this timer
Eight fifteen-second sprints with forty-five seconds to walk back to the line, run twice. The 1:3 work-to-rest ratio is the standard for speed-endurance work: long enough to recover most of your output, short enough that fatigue accumulates across the set. Fifteen seconds is roughly a hundred metres for most people, which is why the walk back doubles neatly as the rest interval.
Best for
- Any sport with repeated sprint efforts
- Building speed endurance rather than top speed
- Track, pitch or treadmill