HIIT workouts, which is best?

I was asked last week about interval training and the differences in timings. When people ask me this I’m reminded of how much information is actually out there for people and how confusing it can actually get.

So, when it comes to HIIT which is best? 30/30, 30/15, 20/10?

Incase you’re unfamiliar with those numbers, they are timings for work/rest periods within your workout

30 work
30 rest

However, believe it or not these aren’t arbitrary numbers that people just make up.

HIIT vs LSD

We have different energy systems within the body that get us from A to B depending on how fast we are traveling.

Best example, the energy system that Usain Bolt uses is different to the one Mo Farah uses.

Speed and Power (high intensity anaerobic exercise)
vs
Distance and Endurance (long slow distance)

Without going in depth into a massive biology and anatomy lesson here I’ll keep it brief.

As the body needs oxygen we can only work at an anaerobic high intensity state for so long before we have to stop and replenish the oxygen in our muscles.

With the aerobic energy system we could go for days – hence long slow distance. Example: Forest Gump (ok, not a real life example but a good one).

High intensity interval training (HIIT) works the body in the anaerobic system and aims to work you so hard that by the time you’re resting, you’re out of breath, your muscles are burning, you’re drenched in sweat and you’re wondering why you’re doing this.

Once the rest is over you shouldn’t be fully recovered before you go again.
^^This is where the magic happens.

By not fully recovering you are creating an oxygen debt that must be ‘paid back’ after the exercise is over.

This increases the oxygen intake after your workout a.k.a EPOC (excess post-exercise oxygen consumption).

This is why interval training has taken off – unlike with aerobic exercise –  we continue to burn calories once the workout is done as our body is replenishing and repairing after the intensity of the exercise.

This is known as the afterburn effect.

^^^ as a side note, you might read that you burn more calories for up to 24 hours after the workout. Keep in mind that the time spent recovering is directly related to

How hard you worked
Your current fitness level
Your current muscle mass
Gender

In textbook terms interval ratios can range from 1:1/2 to 1:3 depending on the goal.

So which is best?

If you’re a recreational exerciser (i.e not an athlete with a coach) then the intervals that you find challenging but enjoyable are the ones to go for.

Can you handle 30/30 but you dread 30/15?

Stick with 30/30.

As you get fitter you might prefer 30/15

OR

You’ll stick with 30/30 and work even harder

The workout that you do consistently is the one that will give you the best results.

No point reducing your rest if you skip the workout through not being motivated enough to complete it.

As with everything in health and fitness there is no one way to exercise. So if you can’t stand interval training and wonder why anyone in their right minds would do it – choose something else.

If you love intervals and they’re giving you results – stick with it.

The only way to know if something is for you is to try it and see how you feel.

But when it comes to exercise, the ratio of work to rest during your intervals is a long way down the list of things to worry about.

Consistency first.
Details later.

Ainzlie “20/10” McMaster

p.s – not all workouts need to be intense, focus on bringing all of your energy to every single workout to keep up your motivation and results.