Fine Tune Your HIIT

High Intensity Interval Training isn’t a new thing, but the term “HIIT” has become a bit of a fitness buzzword, meh, that happens a lot in this industry, we get used to it.

Interval training is great for many reasons; it’s highly specific to sports, it doesn’t take much time, and it’s been shown time and time again to be very effective at increasing aerobic power, VO2 max, time to exhaustion etc.

In this short article, I’m going to highlight a few problems that are evident when employing HIIT

All out efforts aren’t sustainable.

Let’s just imagine we go absolutely bananas (read: 1000%) on a 30 second bike sprint, rest 30 seconds and then attempt to repeat the process. This is a pretty typical work to rest ratio and one I employ regularly. The problem for most is that a 30 second max sprint completely ruins them and maintaining repeat efforts anywhere near that quality just isn’t on the cards. True they are working hard and for most people it will of course improve their fitness, but is it the most effective way to use HIIT training? I say no.

You’re Going Too slow.

High Intensity Intervals are only effective if the intensity is high (stares blankly😑). For example, if you can run 3km at 12km/hr then your interval speed needs to be much faster than 12km/hr it seems like common sense and really, it is, but I’ve seen it plenty of times.

Lack of Progression.

Unlike resistance training, conditioning is often times approached with a blasé attitude in regard to progression. Just like resistance training your conditioning program should include progression through the manipulation of reps, sets, volume and intensity. Without a solid structure to your conditioning your improvements will begin to plateau.

The Fix and the Freebie

To address the first two problems, we need to find a middle ground that gives us an ideal intensity to work at to make the most effective use of our interval training sessions. Luckily, super smart sport scientists like Gregory Dupont, Martin Buchheit, Izumi Tabata and Dan Baker have done most of the work for us, and I’ve made it even easier for you.

Using what we call Maximal Aerobic Speed or MAS which we can easily estimate using a time trial test, we can calculate specific speeds and distances to be used for our interval training.

Without using fancy fitness tests, an easy way to estimate our MAS is to use a set distance or set time and use the following calculation. Distance(m) / time(s), for example 1.5km in 5 minutes would be calculated as 1200/300 = 4m/s. This can and should also be used for bike and row ergometers, the same calculations apply. Note: It is advised that you use a test of 5-6 minutes in length.

But hold up, that’s just an average speed, right? We know that we need to work harder than that during our high intensity intervals. Luckily again those smart guys have figured out that approximately 120% of our MAS is the most effective at providing a training stimulus in terms of Intensity x Volume. So, we simply multiply our MAS by 120%, using the above equation that would mean we do our intervals at 4m/s x 120% = 4.8m/s. To keep things simple, you can then multiply 4.8m/s by 3.6 to convert from metres/second to kilometres/hour and arrive at a speed of 17.2km/hr (pretty damn fast). You can also work the other way and figure out a distance to be covered for a given interval length, for example 4.8m/s x 15s = 72 metres.

Hopefully I haven’t confused you with all the conversion etc and you’re still interested. If you are, here is your reward (if you call it that). A free 3-week program and MAS interval calculator. The good news is that you can retest and continually use the program as well as use it for running, cycling and rowing intervals (I’ve even thrown in a km/hr to pace converter). The bad news is now you have no excuse but to get stuck in.

Here's the link to download the file

All I ask is that you let me and/or social media know how it’s going - @smiths_fitness #SmithsFitness




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