9. Frequency
If you're completely new to HIIT, start slow with just one HIIT workout a week. Once you get more comfortable, you can increase it to three or four times per week.

It's important that you listen to your body and understand that it's perfectly fine, and smart, to take time off between workouts. HIIT does not have to be all or nothing — slowly start incorporating it into your workout routine and you'll start building your endurance before you know it.