HIIT or LISS — sokav

So you’ve started going to the gym, or bought yourself a cardio machine to use at home. Amazing! You’ve also probably spoken about it at work and some of the more experienced gym goers at work or personal trainers at the gym have recommended doing HIIT. If you were wondering what it is, then we are here to help.

LISS

Let’s start with LISS, also know as Low Intensity Steady State (cardio). This is basically any form of cardio (running, rowing, cycling etc.) where your heart rate is between 50-70% of your maximum heart rate constantly through out the workout. Now you are probably wondering what your max heart rate is. Well, as with most things, there is a simple formula:-

Max HR = 220 – Age

For example, my max heart rate is 183 (can you guess my age, in a few months)

This means my LISS heart rate is somewhere between 90 and 130 beats per minute. Depending on your fitness level, LISS could be as simple as walking. However, some of you might already have a strong cardiovascular system, where your heart is able to pump lots of oxygen to your muscles, in which case, LISS might be a slow pace jog or back stroke in the swimming pool.

When would you do LISS?

LISS can be used to:-

Warm up – to get the heart ready for an intense workout

Cool down – this very useful after a resistance workout, to pump oxygen to the muscles worked.

Burn Calories – very useful in fat loss. Research shows LISS uses body fat as the main source of fuel.

Rest days – I use LISS actively on rest days. They are usually in the form of walks to burn calories and minimise high impact activity.

Low impact workouts – LISS puts less stress on the body and joints.

HIIT

Now to HIIT, also known as High Intensity Interval Training. This is where you perform an exercise, raising your heart rate between 70-90% of your max heart rate for a short period of time, then lowering to 60-65% for a short period. You repeat this sequence as many time times as you desire. Continuously raising your heart rate above the 70-90% zone and lowering allows you to burn the desired calories in a shorter period.

A good example of HIIT would be to sprint for 20 seconds and rest/walk for 20 seconds. As you get fitter, you could turn this into 30/30, 20/10, 40/40. Experiment as you desire. You can also perform other exercises in the “on” stage, such as burpees, box jumps, skipping, anything that gets your heart rate up and simply rest in the “off” stage.

Look out for a future blog on simple but effective HIIT workouts.

When would you do HIIT?

Short of time – HIIT is effective in burning approximately the same amount of calories as slightly longer LISS session.

Resistance training – well this is already a form of HIIT. Let’s put this into perspective. As you lift the weights, your heart rate increases. Once you complete the set and have your rest, the heart rate decreases.

At home – without any cardio equipment, HIIT can be performed at home via burpees, squat jumps, mountain climbers, push ups etc. None of these require equipment and can also help build lean muscle.

Burn Calories - There is a school of thought that HIIT burns more calories, which in turn helps burn more fat. However, HIIT is also known to use glycogen stores before tapping into the fat reserves. Additionally, it is thought that HIIT burns more calories after the workout. I am undecided on this as it would suggest the heart is working harder after the workout, and my trusted FitBit shows I haven’t burnt any more calories compared to non-HIIT days.

Somewhere in between

There is another type of workout, called MISS. Yes, MISS. MISS is Moderate Intensity Steady State cardio. This works the heart rate at approximately 60-80% of your max heart rate for a continuous period. Examples include steady state running, long distance cycling, rowing etc.

My choice?

I do both HIIT and LISS, often on the same day when I am trying to achieve a calorie deficit. My workout routine includes resistance training at the gym, followed by a form of HIIT (or Metcons – see future post), followed by a 1 mile walk home (LISS).

However, when I am trying to achieve a calorie surplus, I cut out the HIIT and Metcons (on most days).

MISS, well I just miss this out altogether, because it is just too boring. I find it boring to be running, cycling at the same intensity for a long period. However, if this is what you prefer, then it is not something to be ruled out.