High Intensity Aerobic Intervals (HIIT)

This long and challenging interval workout is a type high intensity interval training (HIIT) that helps build endurance, increase your anaerobic threshold and burn more calories and fat both during and after your workout.  For the workout, you'll have 10, 4-minute high intensity intervals in which you work at a Level 8-9 on this perceived exertion scale.  You should be working hard, but be able to sustain this level for the full 4 minutes. In between these intervals, you'll get a 2-minute rest where you'll do very light movement to recover. As you get tired, you may need to slow down or lower your incline/resistance to maintain Level 8-9.  Don't be a slave to your settings, but change them to stay within the suggested levels.
This is a very challenging workout, so modify the sprint intervals as needed to fit your fitness level and goals.  You can do this workout on any cardio machine (set to manual mode) or with any outdoor activity such as walking, running or cycling. This workout is best for intermediate or advanced exercisers.

Time	Intensity/Speed	Perceived Exertion
5 min.	Warm up at an easy-moderate pace	4-5
4 min.	Gradually increase your speed, incline and/or resistance until you're working at an intense pace.  You should be out of your comfort zone and breathing hard, but able to sustain this level for the full 4 minutes.	8-9
2 min.	Reduce speed to a very light pace to fully recover	3-4
4 min.	Increase your speed, incline and/or resistance until you're working at an intense pace.	8-9
2 min.	Reduce speed to a very light pace to fully recover	3-4
4 min.	Increase your speed, incline and/or resistance until you're working at an intense pace.	8-9
2 min.	Reduce speed to a very light pace to fully recover	3-4
4 min.	Increase your speed, incline and/or resistance until you're working at an intense pace.	8-9
2 min.	Reduce speed to a very light pace to fully recover	3-4
4 min.	Increase your speed, incline and/or resistance until you're working at an intense pace.	8-9
2 min.	Reduce speed to a very light pace to fully recover	3-4
4 min.	Increase your speed, incline and/or resistance until you're working at an intense pace.	8-9
2 min.	Reduce speed to a very light pace to fully recover	3-4
4 min.	Increase your speed, incline and/or resistance until you're working at an intense pace.	8-9
2 min.	Reduce speed to a very light pace to fully recover	3-4
4 min.	Increase your speed, incline and/or resistance until you're working at an intense pace.	8-9
2 min.	Reduce speed to a very light pace to fully recover	3-4
4 min.	Increase your speed, incline and/or resistance until you're working at an intense pace.	8-9
2 min.	Reduce speed to a very light pace to fully recover	3-4
4 min.	Increase your speed, incline and/or resistance until you're working at an intense pace.	8-9
5 min.	Cool down at a very easy pace.	3-4
Total :	64 Minutes