Why your HIIT classes are not working...

Screen Shot 2019-01-20 at 19.19.00.png

What is HIIT?

High Intensity Interval Training is made popular by many trainers and coaches world wide as the magic solution to get a “savage workout” in a rapid time frame. The research even goes on to promise the “after burn effect”


Excess post-exercise oxygen consumption (EPOC, informally called afterburn) is a measurably increased rate of oxygen intake following strenuous activity.

Here’s the WIKI description

From Wikipedia

Excess post-exercise oxygen consumption (EPOC, informally called afterburn) is a measurably increased rate of oxygen intake following strenuous activity. In historical contexts the term "oxygen debt" was popularized to explain or perhaps attempt to quantify anaerobic energy expenditure, particularly as regards lactic acid/lactate metabolism;[citation needed] in fact, the term "oxygen debt" is still widely used to this day.[citation needed] However, direct and indirect calorimeter experiments have definitively disproven any association of lactate metabolism as causal to an elevated oxygen uptake.[1]

In recovery, oxygen (EPOC) is used in the processes that restore the body to a resting state and adapt it to the exercise just performed. These include: hormonebalancing, replenishment of fuel stores, cellular repair, innervation and anabolism. Post-exercise oxygen consumption replenishes the phosphagen system. New ATP is synthesized and some of this ATP donates phosphate groups to creatine until ATP and creatine levels are back to resting state levels again. Another use of EPOC is to fuel the body’s increased metabolism from the increase in body temperature which occurs during exercise.[2]

EPOC is accompanied by an elevated consumption of fuel. In response to exercise, fat stores are broken down and free fatty acids (FFA) are released into the blood stream. In recovery, the direct oxidation of free fatty acids as fuel and the energy consuming re-conversion of FFAs back into fat stores both take place.[3][4][5]

In short it means how your body recovers from that session… BUT what type of HIIT should you do and why?

Screen Shot 2019-01-20 at 19.00.45.png

Okay so when you are training at HIIT or a desired HIIT training session, what you need to understand that is if you are not good at the exercises, you will probably get hurt. I know this sounds simple, but you would be surprised. You see as much as jumping lunges are a great exercise, and burpees seem to be a universal staple of all HIIT sessions, what is the point if the exercise prescription doesn’t match up with the science or physiology of your body? What does this even mean? not to mention your own abilities.

Well for a start, when you do explosive movements like burpees you use CHO (carbohydrate) as a form of energy because they demand FAST TWITCH MUSCLE FIBRES, and what are they?

Type II) muscle fibers. These fast twitch fibers can be further categorized into Type IIa and Type IIb fibers, which are also known as "fast twitch oxidative" and "fast twitch glycolytic," respectively.

Slow-twitch muscles help enable long-endurance feats such as distance running, while fast-twitch muscles fatigue faster but are used in powerful bursts of movements like sprinting. FATIGUE is the main issue here.

The best way to train these is through power, typically with strength based exercises like heavy squats. Now where strength translates to athletic moves like burpees is pretty simple. If you have a good strong back squat or front squat, you will benefit more from burpees. It would make sense wouldn’t it?

The Basic Requirements and common sense approach

If john weighs 80kgs and he starts doing 10 burpees, john must move 80kgs x 10 reps , fast well co-ordinated and explosive, it might take John 50 seconds to do these 10 burpees if he’s out of shape and sometimes longer. For the sake of argument, he’s dealing with 800kg of load with no previous strength training, stability or foundation.

If John has a back squat of 80kgs however (his own bodyweight) he will be now more efficient at producing this power from the ground up and therefore better suited to this exercise and should be able to do the 10 burpees in about 30 seconds. , now John is moving the same weight but because he is now STRONGER. These are less laborious, safer, because he has a foundation behind him.

Can you do burpees without having some strength foundation, YES, is it a good idea… no, not really. What is a good place to start?

BASIC STRENGTH like the classes we teach on Saturday mornings at 9am. Here is some points to work on in the squat to help your lower body strength.

Anyways. What should you do if you ENJOY HIIT Training. You should do these 3 things.

  1. Do aerobic base training, get used to training for at least 2 minutes at a time in the 130bpm HR zone with 1 minute rest. This work to rest ratio is 2:1 with is a form of intense training.

  2. Do anaerobic training, get used to training with insufficient levels of oxygen in your conditioning HR zones. A combination of aerobic and anaerobic base training is vital to any success in the HIIT type training.

  3. Get a base of strength established or it just won’t work the way you want it to. Stronger people benefit more from HIIT. HIIT is also relative is why we have a unique HIIT class on a Saturday morning thats gives you all of these attributes.

Screen Shot 2019-01-20 at 19.00.13.png

Let me put it tis way an MMA fighter fights for 5 minute rounds with 1 minute rest x 3 to 5 rounds. His or Her requirements are a 5:1 work to rest ratio in the conditioning HR zone. You’re probably not a MMA fighter and let’s say you are doing a HIIT workout with 40 seconds work and 15 seconds rest and there is 5 exercises.

55 seconds in total, give 40 is work and 15 is rest.

Work : 40 x 5 = 3minutes and 33 seconds

Rest 1 minute 25 seconds rest.

So your work ration is 3:1 here, just like a boxer, or martial artist when they fight. So now let’s look at possible exercises and what the problems are, other than HR going from 120-180, most people start to bonk after 160bpm, because…… that’s what happens when you are untrained.

1: Swings (Aerobic into Anaerobic) 45 seconds

2: Burpees ( Peripheral Heart Action response elevated HR) 45 seconds

3: Hill Climbers ( Core and Cardio based, requires push up strength & core ) 45 seconds

4: Kettlebell push press ( 45 seconds , requires strength and power especially 4 exercises in, HR will no be quite high

5. Sprint on the spot 45 seconds ( basic split squat and squat strength required, high power and co-ordination required)

So, you’re in your 30’s out of shape but expected to train like a fighter with high power, speed, co-ordination, HR awareness, for more rounds than fighters spar in some clubs.

Okay….. maybe it’s time to try something else before you get hurt, lose interest or wonder why your body isn’t shaping up the way you want it. You can also train as hard as your engine allows and body is strong or you break down in technique, let alone probably collapse.