What interval training is
Interval training alternates periods of work with periods of rest. The rest is what lets you work harder, or with better form, than you could if you kept going without a break. The ratio sets the feel: equal work and rest suits beginners and strength moves, while short rests between longer efforts make the same session much harder.
An interval timer takes the counting off your hands. Instead of glancing at a clock between reps, you hear when to start, when to stop and what comes next, and you can give all your attention to the movement.
How to use this interval timer
This session is a beginner full-body workout: a ninety-second warm-up, then five simple moves (chair squats, wall push-ups, glute bridges, reverse lunges and bird dogs), each forty seconds on and forty off. After a one-minute break you go through all five again, then cool down, sixteen minutes in all.
The coach calls each move as it begins and tells you what is next during the rest. A tick keeps the pace, the time left is called out and the last five seconds of every block are counted down. For different moves or timings, build your own in Create: name each step, give it a length and run it right here.
Three tips for interval workouts
Match the rest to the goal
Equal work and rest, as in this session, keeps the quality of each rep high and suits strength moves. Cutting the rest, as a Tabata does, turns the same moves into conditioning.
Quality over speed
Use the forty seconds to move well rather than to rush reps. A slow, controlled squat does more for you than a fast, sloppy one, and it is kinder to your knees and back.
Change one thing at a time
When a session starts to feel easy, make the moves harder first, a deeper squat or push-ups from the floor instead of the wall, before you shorten the rests. One change at a time keeps progress steady.
Who it is for
Beginners and people coming back to exercise, mostly: every move here can be done at home with a chair and a wall, and the rests are generous. It also suits anyone who wants a short, structured workout without having to plan one.
For something harder, try the twenty-on, ten-off rounds of a Tabata, or a running session that alternates tempo blocks with recovery walks.