These two cardiovascular workouts have been the focus of much debate throughout the last several years.
Everyone, as usual, is looking at the research and trying to decide what exactly they should be doing to better their health & promote longevity.
The H.I.I.T. vs L.I.S.S. can be a tricky one, but let’s go through the pros & cons of each to determine which is right for you.
They can both have positive & negative effects on fat-loss.

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What is HIIT?
First off, what is H.I.I.T.?
H.I.I.T stands for High Intensity Interval Training.
Essentially, with H.I.I.T. you spike you heart rate for short periods of time (usually 20-45 sec.) and then rest for short periods of time (usually 15-30 sec).
Exercises used in H.I.I.T. workouts must be very explosive, due to the short time interval you will be preforming them for.
Jump squats, burpees, jump lunges, mountain climbers, sprints, rowing, etc.

Due to the back & forth of spiking your heart rate and following it up with a short period of rest, you rapidly increase you cardiovascular capacity.
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Pros & Cons of HIIT
Just like everything else in life, there’s a list of pros & cons. So here are some of the pros & cons of HIIT training.
pros
Increased Cardiovascular Fitness.
okay, so a bit anti-climaxtic this one, but research has shown that HIIT does improve your cardiovascular fitness. The only problem is, researchers haven’t figured out the precise scientific process that allows the body to do so. They just known, from data, that it works.
Time Efficient.
A proper HIIT session can’t last longer than 30 minutes. And 30 minutes is the VERY generous side. Because you fully exhaust your body throughout the active time period, it is impossible to go any longer. If you can go longer, you either weren’t pushing yourself to full exhaustion, or the workout wasn’t challenging enough for you.

cons
Increased Stress.
Because HIIT is high intensity (as the name so obviously suggests) it does stress out the body more than any other form of exercise (walking, running, weight-lifting, pilates, etc.). Therefore, doing too much of this training will have negative effects such as stalled fat-loss.
One of the most difficult things for me to accept throughout my fitness journey is my body’s inability to tolerate HIIT.
I just have a low tolerance for intense training. My body simply doesn’t respond well to it.
When I do too much HIIT (2 or more times a week), my body becomes so inflamed. I get uncomfortably bloated, I hold onto water, my concentration dwindles, and my energy levels, well, lower.
So, I’ve learned to still increase my heart rate, get in my (much needed) cardio, and protect my cardiovascular health without stressing my body out. And that’ where I’ll introduce LISS.
What is LISS?
L.I.S.S. stands for Low Intensity Steady State. So your heart rate is slightly elevated for a longer period of time. Say 30-90 minutes.
This means a L.I.S.S. workout doesn’t involve full body movements that require full exertion.
There’s no burpees, sprints, or jump squats. This makes it the perfect option for someone who has joint problems, or simply hates intense cardio.

Pros & Cons of LISS
Just as with HIIT, there are some pros & cons we should briefly discuss.
pros
Less Stress
Because this is (as the name suggests) low intensity, the stress placed on the body during and after the workout is significantly lowered.
This means your body will allow your body to lose body fat. Stress isn’t good for anything, especially fat-loss.
Less stress can also be great for many other conditions.
Some women with hormone imbalances, for example, find that their body responds best to lower-intensity workouts.
cons
Time Consuming
LISS can be very time consuming. And doing shorter LISS sessions mean slower fat-loss results. Of course, LISS is less stressful on the body as opposed to HIIT.
Spending an hour or two doing LISS everyday isn’t realistic for some people. Jobs, kids, family, life just gets in the way. We feel we have better things to do. But there are several ways to get in LISS without sacrificing everything else in your life (stay tuned for the next active living post).
Recommended Reads on Fitness & Longevity:

The Longevity Paradox

The Energy Paradox
Are you at all struggling to make it through the day without caffeine? Do ever feel like you’re running on fumes? Have you ever fallen asleep at your desk. Whether of not you have experienced any or all of these things, Steven R. Gundry’s The Energy Paradox tackles a common struggle faced by many in our world: the lack of sustained energy.