HIIT question

[pnx]

i usually see HIIT recommendations as sprint/walk.

Can I do interval cycling cycle fast/slow?

Or just any activity that would raise my heart rate up to 90%-100% max HR in 30 secs-1 minute?

How about mixed? Cycle fast, rest,sprint,rest,plyometric jumps, rest, jump rope,rest....

[JoshDunn]

For cycling its better to crank up the difficulty instead of just pedalling faster.

Anything can be done however i'd stick with the same method for the duration of the session. Changing methods without a correct warm up in each method could result in an injury.

[BjsAust]

Think of it as sprint/recover rather than sprint/walk. It can be done as any activity which allows that.

[Jason B]

I'd be careful about getting close to 100% HR, you don't need to.

[Lisa~]

There are a lot of HIIT protocols but the concept stays the same, go hard then recover. I've seen recommendations for:
1 min. intense, 2 min. recovery
30 sec. intense, 60-90 sec. recovery
15 sec. intense, 30-45 sec. recovery

You don't even have to time it. If you are running outside you can sprint a distance, say 10 yards, and walk or jog it back.

Hard or intense is relative to the individual. I don't think measuring your heart rate will really tell you much. Heart rate measurements have a lot of inaccuracies. Measure your interval by how hard it feels to you when you're doing it. An outside measurement, like your heart rate or the numbers on the equipment, are only helpful as a comparison to what you've done before.

pnx, I love your idea of mixing up the activities. It would make your session interesting. It reminds me of doing complexes, which are also great energy system work. You just have to try it and see how it feels when you do it. Over time you will be able to order the activities to be able to keep up the intensity of the intervals.