The Difference Between HIIT and LISS Explained!

They're current buzzwords circulating through the health and fitness world, but if you are new to fitness (even if you aren't!) the acronyms HIIT and LISS may mean absolutely zilch to you.

In today's post, I thought I would give you an overview of what each one means, how they work and if they could work for you- because knowledge is power.

Let's start with... HIIT

Ah- high-intensity interval training AKA you feel like you're dying for a few seconds and then you get to rest annnnnd repeat.

HIIT is set out in a format that will get your heart racing and the sweat pooling off your forehead. How it works is giving you a period of maximum effort work, followed by a period of rest- for example, 20 seconds to go as hard as you can, followed by ten seconds of rest. The key, however, is that during those short bursts of work- you have to really put in the work for HIIT to be effective.

A HIIT workout will typically last you between 20 - 30 minutes, this is something you do for a short period of time, and try to avoid doing sessions back to back. You are usually recommended to do around only two sessions of HIIT per week.

HIIT is very flexible in the sense of how it is formatted. There is a variety of different ways that you can get your heart rate up during that all-out-hard-work period. Cardio exercises such as swimming, cycling, rowing and running can all be incorporated into a HIIT routine. So can strength movements such as squats, burpees, push-ups.

Why would you want to do HIIT I hear you asking. Well, here are a few benefits to adding in the odd high-intensity session:

  • It is an efficient method of expending energy. During this workout, you will work to your maximum, which is when you will really have to dig deep for that energy to continue on.
  • It has a high afterburn effect. Post workout, once you've cooled down and regained the ability to breathe again you will actually continue to burn calories.
  • Health benefits could be included improved cardiovascular health, cholesterol profile and improved insulin sensitivity.
  • Increases your endurance ability.
Alright, I've told you the benefits, now let me give you the less positive side of HIIT and things you need to consider before adding it into your routine. 
  • HIIT, as suggested in the name is very high intensity, meaning it can be very stressful on your joints- in particular, the knees and ankles. 
  • It shouldn't be used as a sole form of exercise. As I said you should avoid back to back sessions and limit to only two per week, HIIT is very taxing on the body and should be limited. 

And now lets chat LISS

LISS stands for low-intensity sustained state (some people also use low-intensity steady state- it just depends who you are talking too) an is pretty much the opposite of HIIT. 

LISS means you are performing low-intensity cardio for a longer period of time- think around 30 minutes to an hour. Exercises and movements that you could use include walking, cycling, the stair master and swimming. 

Okay, okay- give me the pros!

  • LISS is ideal for rest and recovery days! While we still want to move your body while taking a day off taxing physical activity, adding in an hour or so of LISS will help you still feel as if you have accomplished something.
  • It is perfect for beginners and the young at heart. If you are taking that first step into a new fitness journey LISS is a great place to start and ease yourself in. If you are older and want to take things easier than a HIIT session, a couple of LISS sessions per week will get you feeling good.
  • There is a low risk of injury involved in LISS- you aren't jumping around like crazy, nor are you sprinting for the hills. LISS is nice and steady and means you are less likely to come away needing weeks off because of injury.
  • Minimum effort required. Some days you just do not have the energy to move and that's okay! LISS is perfect for those days because you really don't have to use all that much energy to get the job done.
  • You can do LISS as often as you like- every day if you feel up for it! It isn't taxing or demanding on the body so we only need a short amount of time to recover from it. You can even use LISS as a cool down after a higher intensity session. 
Annnnnd the cons:
  • You are going to need a bit more time on your hands to get some LISS in. A few minutes won't do much at all- you need to give it a good thirty minutes at least.
  • There is no afterburn effect with LISS- once you finish you stop expending energy and you stop burning calories. 
So there we have it- a basic rundown of HIIT and LISS as well as the pros and cons of each so you can make an informed decision about whether you want to include them in your next training routine. 

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