High Intensity Interval Training, otherwise known as a HIIT workout, relies on two different intensities. Very hard and very easy (recovery).
The very hard is usually a result of intense, short bursts of movement, typically from compound exercises (moves that involve the movement of more than one joint at a time), followed by periods of full recovery or rest.
What are the benefits of HIIT?
In a nutshell, HIIT can:
- Increase VO2 max, cardiovascular fitness and stamina
- Increase muscle mass and fast-twitch fibres
- Increase speed, power, coordination and agility
- Regulate glucose levels
- Improve bone health
- Improve mood and stress levels
- Deliver you a challenging, fast-paced workout in a short period of time
How Do I Do HIIT?
There is no one size fits all type of HIIT, you can use your own body weight and do things like burpees, squat jumps, skipping rope or sprinting, or you could hop on a bike or an elliptical to get the same intense results. The only no no is it shouldn’t be done with heavy weights as the speed of the movement can easily compromise your form, leading to an increased risk of injury.
There is also no universally agreed duration time. The intense work periods may last anywhere from 10 seconds to three minutes, and are performed at 80-95% of your maximum heart rate. Compared to endurance (zone 2)cardio that should be around 70% of your maximum heart rate. That said, since most of us don’t have a heart rate monitor, HIIT can be explained in that it is so intense you can only squeak out a word or two, whereas endurance cardio should allow you to maintain a breathy conversation.
The recovery period on the other side can be anywhere from 10 seconds to as long as you need to get your heart rate back down to 40-50% of your maximum heart rate.
How Do I Know My Maximum Heart Rate?
Your maximum heart rate is literally that. The highest rate your heart can beat. And for everyone that is individual, based on their heart and their current state of conditioning. That said, a VERY generic formula is you take the number 220 and take away your age, and that will give you a general idea of what your maximum heart rate might be.
For example, if you are 60 years old, by this formula your maximum heart rate should be 160 beats per minute. And so a heart rate of 128 – 152 beats per minute is what would be considered the range for HIIT.
That said, I don’t monitor my heart rate when doing HIIT training, I go by what is called RPE, or Rate of Perceived Exertion.
What is RPE and How to Use it
The rate of perceived exertion (RPE) measures the intensity of an exercise, using a score of how difficult a particular exercise feels while you’re doing it.
RPE isn’t a difficulty rating of an exercise, it’s a subjective rating that’s based on how YOU feel physically and mentally. It uses a scale of 1-10 as a guide, where 1 is the least difficult and 10 is the most difficult.
A warm up for example, may be an RPE or 4 or 5, whereas HIIT done properly should be in the 8 – 9 out of 10 level. After you’ve done the intense part of HIIT, there is always a recovery, recovery should be around 3 or 4 on the RPE scale – during which you can easily hold a conversation.
Example of a HIIT Workout
There are so many examples of HIIT workouts but one of the most popular is a Tabata.
Tabata:
It is a HIIT workout that alternates between 20 seconds of work and 10 seconds of rest for eight rounds. Your session ends up lasting only four minutes (not including a warm-up or cooldown) long. I usually do two rounds of this, equaling 8 minutes of HIIT, with a warm up and a cool down added on top of course.
15/35, 20/40, 30/30:
You can structure your work to rest ratio in various way. Just make sure you can give it max effort each set.
So, you could do workouts that use 15 seconds work, 35 seconds rest or 20 seconds work, 40 seconds rest or 30 seconds work, 30 second rest. These are good for beginners.
For more advanced fitness levels, you could do 40/20 (40 seconds work, 20 seconds rest).
For these kinds of workouts, you can do circuits of various HIIT exercises or just one exercise. It’s up to you!
In any case, the goal is to get up to 80-95% of your max heart rate each set, then rest. You do the exercise(s) at max effort, then the rest is just enough so you recover, then you go at it again. This will allow you to reap all the real benefits of HIIT workouts.
