I’ve spent the greater part of my life helping people with their workouts in the gym. I’ve been a personal trainer for over 10 years and I have been coaching others online for the last 6! One thing that I have to remind myself is that most of the people I help may not understand what I am saying. If I am speaking a different language then how can I expect my clients to follow my plan or advice! I have always spent time explaining what I mean when I use certain terms, so I figured that it would be best if I wrote an article for you so that you can better understand gym lingo and make more gainz!


HIIT cardio stands for “high intensity interval cardio” and is the current best theory to perform for maximal fat loss. This type of cardio involves training at near 100% intensity with rest periods functioning around 50%. Don’t confuse HIIT for HIT (high intensity cardio), which is as close to 100% intensity for the duration of the cardio. HIIT cardio can be performed for longer periods of time that will have periods of elevated heart rate followed by a drop in heart rate during the resting periods. Don’t mistake the rest as sitting around and doing nothing. Some HIIT cardio programs will require rest to be at 0% intensity, but most will require that you continue moving at a slower pace during your rest period.


LISS cardio otherwise known as “low intensity steady state” cardio is another popular method for fat loss. This type of cardio requires that one perform longer durations (up to an hour or more) at a low intensity. This can be a brisk walk on the treadmill or slow pedal on the stationary bike. This type of cardio centers around getting the heart rate in a target “fat loss” range and then keeping it there.

There is still plenty of debate about LISS vs HIIT cardio and which one is best for fat loss. The truth is that both have anecdotal proof to work as well as scientific literature to back their claims. The best answer is that both are better than nothing. If you don’t have the time then you should do HIIT since it requires less total time in the gym. If you enjoy cardio (because you’re a crazy person) then LISS may be for you since it isn’t as intense and should be done for longer periods of time.


The best way to describe the difference between the two is to take a closer look at the intensity and total stress on the muscles of the body. Aerobic exercise is typically lower in intensity and does not put much of an immediate strain on the muscles of the body. Think about long distance running or cycling. Those two forms of exercise would be more aerobic than anaerobic.

Anaerobic exercises like weight lifting require a lot more intensity during a short period of time. The energy demands change based on the intensity and length of the exercise at hand.

Aerobic activities use oxygen as part of its process to generate energy. This allows the muscles to conserve fuel and last longer. Think of this type of training being similar to driving a hybrid vehicle. Sometimes you need to use gas when driving hard, but other times you don’t need gas and can cruise at an optimal speed without it. If you get to speed then you can go long distances without the need for gasoline.

Anaerobic activities have a higher immediate demand for energy and will use other methods aside from oxygen to generate and burn fuel. Think of anaerobic exercise as a V8 that produces a lot of power but gets bad gas mileage. You can drive it hard, but you certainly can’t drive it for very long.

 So the main difference between the two in relation to the HIIT and LISS examples above is that weight training, HIT, and HIIT cardio will be more anaerobic in nature than aerobic if the intensity is high enough. LISS will be more aerobic in nature as the intensity is low.

Now that you understand these terms let me give you a test. I want you to try and understand the following directions:

“I want you to perform 10 minutes of HIIT cardio on any machine of your choosing to warm up. After you complete the HIIT cardio then I want you to spend 45 minutes training anaerobically. After you finish the anaerobic training then I want you to perform 30 minutes of aerobic LISS cardio on any machine of your preference to cool down. ”

Take this time to use the article and try and decipher the paragraph…

Ok…time’s up…here is the translation:

“I want you to get on any cardio machine and go as hard as you can for 1 minute followed by going at 50% for 30 seconds. Repeat this process for a full 10 minutes. After you complete that cardio, I want you to train with weights while keeping your rest periods down. I want you to train intensely and only let the workout last for roughly 45 minutes. After you finish your workout then I want you to perform 30 minutes of slow and steady cardio on any machine of your choosing as you cool down.”

If you were able to translate that then congratulations! You can now speak the gym language that much better! If you weren’t able to translate that then don’t worry! You’re still learning! Stay tuned for more explanations of the Gym Vocabulary!

Let’s get better together!

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