I decided to pick up HIIT recently to compliment my resistance training. I've read that in a good round of HIIT, you want to alternate intensity levels btwn ~90% for high intensity and 50-60% for the recovery intervals. Should intensity level be measured in terms of max heart rate or something else like max power (watts) that you can exert in a short burst?

I'm also confused as to the proper ratio of time at high intensity to time at rest. Obviously you have to start out with more recovery time relative to intense time until your fitness improves, but some places suggest doing as many cycles as possible at a 1:3 ratio of intensity:rest while the original study that prompted all the discussion on the issue found that 2:1 for very brief periods was optimal.

My last question is about the best types of exercise to perform HIIT with. It seems like stationary bikes and ellipticals are ideal since you can speed up and slow down instantly unlike with a treadmill. Are there any other good forms of HIIT? And is it better to keep resistance low and rpms high or up the resistance and decrease the rpms assuming both lead to the same HR and power?

not too experienced in HIIT, so will offer what i've read up about.

as far as intensity levels, i believe its a matter of "perceived" exertion. so what FEELS like 50% and 90% or whatever. i know, very arbitrary, but theres really no exact way, is there?

i've read different ways to do it. one way was, an all out sprint (ie- 100%) for 30 seconds, then a jog @ like 5mph for 1:30. repeat for like 15-20 min. another that i read was more intense, i believe it was like:

min 1: 1 (exertion leve)
min 2: 2
.
.
.
min 10: 10
and then work your way back down.

i actually like to do any kind of interval training on the treadmill. but i guess you can do it on anything. the idea is to have spurts of all out 100% (or close to it). with the bike i guess you can vary it up, you can go from low resistance to high, keeping rpms the same, or keeping resistnace the same and up the rpm. bottom line is to vary the your intensities.

not sure i gave much, but hope it helps a little =)

Just try insanity it will kick the living crap out of you.

Ben90X wrote:


Well I've read about a couple ways to determine intensity but I'm not sure which is best. Some people sprint all out out on whatever machine they use for 10 sec and use their max speed/power/rpms as their 100% value and use that to plan the intensity of the hard and easy intervals. Other people use max HR as their 100% intensity level.

The other hard part is deciding how to plan out the times. A lot of people suggest that the rest period should be sufficient to bring your HR down significantly, which takes anywhere from 1.5-3 times as long as the intense interval. But the original study used a very different version of 20 sec on 10 sec off for 8 cycles, and there's definitely no way HR could slow down enough during that 10 sec so I'm not sure whether or not letting your HR come back down most of the way is important or not.

sprint/rest ratio depends on current fitness level. there are hundert ways to do HIIT

it can look like this for beginner 2-3 x HIIT/week

week 1 sprint 100 run 300m repeat once more
week 2 3 times
week 3 4 times
week 4 5 times

then more advanced

week 1 sprint 100m, run 200
week 2 3 times etc etc


there is lot more combination to make hiit more advanced, you can run the same distances but faaster or incerase volumen