Tabata or HIIT timers usually have the ability to set a (optional) warmup time, then altenating "work" and "rest" periods, repeating a set number of times.
I previously used one called "Tabata" on my Garmin 945 but 6mo after the 965 has been released, this app is still not available by the developer (I've requested it several times). Does anyone use a timer that you like on your 965? Looking for suggestions, thanks.