2 minute intervals

[Unreal]

I've started to do HIIT type training again, and have been doing 2 minute intervals. 4.0mph low speed, then 8.3-8.5mph high speed on the treadmill. 12 minutes total, 2 minute walk, 2 minute run, repeat. Then usually about 5 minutes to cool down and try not to puke. Should I switch it up to shorter one?

[MixmasterNash]

What's your goal?

[Unreal]

Fat loss, cardio performance, general conditioning. Felt like I was going to die yesterday. Heart rate peaked out at over 170. Definately a workout.

[Anthony]

The general consensus is that shorter intervals are better. But lots of people make good progress with longer intervals.

[MixmasterNash]

I recommend a heart rate monitor. Pick some reasonable interval times, and measure progress by recovery time of heart rate.