[oh_sigh]

c25k isn't HIIT(high intensity interval training). It is just IT.

HIIT would be more like (sprint for 30 seconds, jog for 30 seconds) * 8

[jcmoscon]

Also, take a look at Tabata exercises. It's basically 20 seconds of HIIT and 10 seconds of rest. 10 minutes of it and you are sweating a lot!

[vidarh]

10 minutes of Tabata is pretty extreme... Starting at 4 minutes will leave beginners collapsing on the floor if they push themselves to the max...

[deanproxy]

I love Tabata! I usually use the "Tabata This" workout from Crossfit (one of the few workouts I use from that methodology). I break it up like this: Squats, Pushups, Pullups, Jump rope, situps. So the total routine is about 20 minutes including the 1 minute rests in between each round.

I have started people off on a single round of Tabata which is only 4 minutes (minus the warmup/cool down periods) and it leaves them laying flat on the floor if they push themselves to their limits.

[beedub13]

I will second this. There is a Tabata class at the local YMCA. They have great modifications for beginners to advanced.