High-Intensity Interval Training Guide

High-intensity interval training (HIIT) workouts involve a warm-up period; several short, maximum-intensity efforts separated by low-intensity recovery intervals; and a cool down period. The period of alternating effort and recovery intervals typically lasts 10 to 15 minutes. Including the warm-up and cooldown, the total length of the workouts will be around 15 to 20 minutes.

15 to 20 minutes of HIIT is more effective towards fat loss than an hour or more of slow boring cardio that’s done at a low enough intensity to allow you to watch TV or read a magazine while you exercise.

HIIT Interval Ratios

HIIT work and recovery intervals are expressed as a ratio. For example, a 1:3 HIIT ratio means that your recovery intervals are three times as long as your work intervals. An example of a common 1:3 HIIT ratio is 20 seconds of work followed by 60 seconds of recovery. Other common HIIT ratios are 1:1 (e.g. 20 seconds work followed by 20 seconds of recovery), and 2:1 (e.g. 20 seconds of work, followed by 10 seconds of rest; also known as Tabata intervals).

1:1 HIIT intervals, and any intervals where the work period is longer than the recovery period, are extremely tough, so you will likely need to work your way up to that level. If you’re just getting into HIIT, you should start with recovery intervals that are at least three times as long as the work intervals (e.g. 1:3).

Your work intervals should be done at an intensity so difficult that you couldn’t possibly maintain that intensity for one second longer than the length of the interval. Using the 1:3 work/recovery example, your work interval should done at an intensity that you can keep up for no more than 20 seconds. After 20 seconds, you should be so tired that you have no choice but to slow down for 60 seconds and recover.

Your recovery intervals should be done at an intensity low enough to allow your heart rate to slow down so that you’re ready for another maximum intensity interval after the recovery period is over.

Rating Of Perceived Exertion Scale

The rating of perceived exertion (RPE) is a scale that is used to determine the level of intensity that you will be exercising at. The scale is goes from 1 to 10 — the higher the number, the greater the intensity of your workout. Many RPE scales break down the different numbers by simply labeling them as “very easy”, “easy”, “moderately hard”, etc. I think that those labels are very unclear, so I’ll break down the various levels of the RPE in a way that I think will be much more helpful for you in determining the level of intensity that you will be exercising at.

  1. Relaxing on the sofa.
  2. Moving, but could maintain this pace all day long.
  3. Comfortable, but breathing slightly harder than normal
.
  4. Breathing harder, but can effortlessly carry on a conversation.
  5. Slightly uncomfortable, but can still talk fairly easily.
  6. Slightly breathless, talking is becoming difficult.
  7. Breathing is labored, talking is difficult.
  8. Uncomfortable, gasping for breath, can’t talk.
  9. Extremely uncomfortable, could only maintain this pace for about ten seconds.
  10. Maximum effort, could only maintain this pace for a few seconds.

Throughout the HIIT workouts in this guide, when suggesting the level of intensity that you should be exercising at, I will reference different numbers of the RPE scale. Refer back to this scale to determine your HIIT workout intensity.

Sample HIIT Workouts

Below are five sample HIIT workouts to get you started on the right track with your interval training. These workouts can be done exactly as they’re laid out here, without any modifications, or you can tweak them however you prefer so that they’re more closely tailored to your own fitness level and goals.

HIIT Hill Sprint Workout

1:3 work/recovery intervals performing high sprints. Sprint up the hill for your work interval, and walk down the hill for your recovery interval.

Warm-up: 3 minutes at an intensity level of 4 on the RPE.

Intervals:

  • Work interval: 10 seconds at an intensity level of 8 on the RPE.
  • Recovery interval: 30 seconds at an intensity level of 3 on the RPE.
  • Perform a total of 15 work/recovery intervals.

Cool down: 2 minutes at an intensity level of 3 to 4 on the RPE.

Total workout time: Total workout time: approximately 15 minutes.

HIIT Jump Rope Workout

1:2 work/recovery intervals performed with a jump rope. During the work intervals, jump rope at maximum speed/intensity. During the recovery intervals, do a light jog in place to allow your heart rate to come down so that you’re ready to push yourself at maximum intensity during the next work interval.

Warm-up: 3 minutes at an intensity level of 4 on the RPE.

Intervals:

  • Work interval: 30 seconds at an intensity level of 8 on the RPE.
  • Recovery interval: 60 seconds at an intensity level of 3 on the RPE.
  • Perform a total of 8 work/recovery intervals.

Cool down: 2 minutes at an intensity level of 3 to 4 on the RPE.

Total workout time: Total workout time: approximately 17 minutes.

HIIT Tabata Bodyweight Workout

2:1 work/recovery intervals performing burpees and high jog. Exercises are meant to be performed individually during two separate tabata sessions — i.e. 4 minutes of tabata burpees, rest, then 4 minutes of tabata high jog.

Warm-up: 3 minutes at an intensity level of 4 on the RPE.

Intervals:

  • Work interval: 20 seconds at an intensity level of 8 on the RPE.
  • Recovery interval: 10 seconds at an intensity level of 3 on the RPE.
  • Perform a total of 8 work/recovery intervals.
  • Take 2 minutes of rest between exercises.

Cool down: 2 minutes at an intensity level of 3 to 4 on the RPE.

Total workout time: Total workout time: approximately 15 minutes.

HIIT Rowing Workout

1:3 work/recovery intervals performed on the Concept2 rowing machine.

Warm-up: 3 minutes at an intensity level of 4 on the RPE.

Intervals:

  • Work interval: 20 seconds at an intensity level of 8 on the RPE.
  • Recovery interval: 60 seconds at an intensity level of 3 on the RPE.
  • Perform a total of 8 work/recovery intervals.

Cool down: 2 minutes at an intensity level of 3 to 4 on the RPE.

Total workout time: approximately 16 minutes.

HIIT Stationary Bike Workout

1:1 work/recovery intervals performed on the stationary bike.

Warm-up: 3 minutes at an intensity level of 4 on the RPE.

Intervals:

  • Work interval: 30 seconds at an intensity level of 8 on the RPE.
  • Recovery interval: 30 seconds at an intensity level of 3 on the RPE.
  • Perform a total of 10 work/recovery intervals.

Cool down: 2 minutes at an intensity level of 3 to 4 on the RPE.

Total workout time: approximately 15 minutes.