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October 18, 2022

173 I When to use HIIT style cardio vs slow and steady (LISS)

173 I When to use HIIT style cardio vs slow and steady (LISS) with Annie Miller

There are several different approaches to doing cardio within the conditioning world. 

Two of the most popularized by the fitness industry are high intensity interval training (HIIT), and low intensity study state training. I think most people understand what LISS is. But high intensity interval training has been very incorrectly marketed to you by main stream media and fitness professionals.

So today we are going to dive into what each of these are, and how to best implement them into your training for their purpose.

There are more types of cardio than this of course. In my Built by Annie premium one and premium two options we include cardio. And it is a rather linear progression from low intensity steady state cardio all the way up into cardiac power intervals. And those progressions are largely taken from energy systems development. You could progress this much much quicker if you were to implement these strategies multiple times per week. And Built by Annie cardio is mainly done one day per week but women certainly see the effects of that progression over the year that they’re inside the program. Doors open October 25th to the waitlist, so make to sure to get on that!

Most people might think that high intensity is inherently better, but that’s completely relative to things like your aerobic base, the goal of your training age, and many other things.

I would argue that most people lack LISS – 

Low intensity study state is traditionally cardio done past 30 minutes, up to 90 minutes or more, in zone two of your heart rate zones out of five. That is typically in the 60 to 65% range.

High intensity would be considered zones four and five, say 80%+ and if you want to be technical it refers to using intervals. So this would not apply to staying in zones four and five for say 12-20 minutes. That would be something called high intensity continuous training, or HICT. And I’ve talked about that and other episodes. That, to my knowledge was popularized by Joel Jamison.

Both approaches have their purpose within conditioning. The idea with high intensity interval training is to get your heart rate up very high for a working period, and then let it recover so that you can go again at the high intensity. This trains the alactic and anaerobic systems.

HIIT is high stress on the body, and may require more recovery and low intensity exercise.

LISS on the other hand trains the aerobic system. It is low stress, low recovery demand, burn some calories, increase aerobic base.

You will likely experience some thing with high intensity interval training known as epoc. Or excessive post-exercise oxygen consumption. This is the period of time where the body is attempting to get you back to homeostasis. It’s restoring glycogen, bringing the heart rate and respiration down etc.

This does increase the caloric demand of high intensity exercise. And yes you may burn calories for a longer period of time after high intensity interval training. My main question would be what is the purpose?

As a coach and professional, the purpose of high intensity interval training, which can be implemented in a lot of ways, would be to train those a lactic and anaerobic systems.

Or as the purpose of low intensity study state cardio would be to increase someone’s overall aerobic threshold, and work capacity base of fitness. And two generally increase caloric output if that is something we’re looking to do. I would choose that over high intensity if the goal is caloric output because, again, there is a lower stress demand and lower recovery demand from low intensity steady state cardio.

If you are going to do high intensity interval training (HIIT), you have some options. I’ve talked to other episodes about being sure to place your cardio where it makes sense for your training goals. Generally speaking of building muscle and strength, and performance is your goal, do cardio after your lift. You will also benefit from the accumulation of fact we’re doing cardio after your lift. Whereas the accumulation effect can have a negative impact on your lift if you do cardio first.

For the working interval of your high intensity interval training(HIIT), you could use working sets at 15 seconds to 60 seconds, and generally speaking, rest would be 3 to 4 times that length. So your work to rest ratio is 1 to 3 or 1 to 4.

That is so that you are getting close to full recovery before you are doing the high intensity work again. I want to repeat that the point of this is interval training, so getting the heart rate up, and then bringing the heart rate back down significantly. Shorter rest periods will keep the heart rate high and somewhat defeats the purpose of doing high intensity interval training. But you could certainly do that and it would just be high intensity continuous training.

You’ll begin to see your threshold as your heart rate starts to not recover between sets. So you can choose to do your sets open ended. Meaning you would just choose a 1 to 4 ratio and then do as many sets as you could before your heart rate starts to not recover. Or, you can choose a higher number of sets if the work ratios are lower, and a lower number of sets if the work ratios are higher. The duration, I mean, not the ratio.

That might look like 8 to 12 sets of 15 second sprints or hill climbs, with a 45 second recovery.

That’s some thing to note with HIIT things that can make the intensity increase our load or resistance. That could be putting on a weight vest or Hill sprints/adding resistance to a stationary bike. These increase the muscular demand in therefore the cardiac in respiratory demand. Making the exercise more intense. The hill provides resistance, the weight vest provides load. You get the picture. Pushing or dragging a sled but also provide load and resistance.

I would always start with low intensity steady state cardio if someone is deconditioned, or if they don’t have a cardiac base. I would implement high intensity interval training if someone has a solid aerobic base. And especially If doing high intensity interval training, placing that after a Lift or separate from a Lift. Unless the lift is complementary to the conditioning.

Remember that any types of cardio I talk about implementing on this podcast, I likely use with my clients inside Built by Annie. Once you experienced this type of intention with cardio, you will likely find it difficult to return to just doing cardio for the sake of doing cardio. Which there is nothing wrong with if there is no goal in mind other than getting some movement in.

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I'm an adventurous introvert from Vancouver, Washington who lives on sleep + "me time." I'm a lover of lifting weights, dinosaurs, real talk and traveling with my husband. I am here to help you move better, lift more, bust the myths of the fitness industry, and inspire you to love the process.

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