L.I.S.S. vs H.I.I.T. Cardio

I’m sure you’ve seen these terms at some point in your exercise career. It may have been in a magazine or maybe on a fitness forum. Typically, the two are argued as to which is better.

LISS (low intensity steady state) cardio is a form of cardio that is low and slow. Think of cooking a pork shoulder. It needs to cook at a low temperature for a long time. Most forms of LISS include walking, stair climber, biking, or any other low intensity activity that can be maintained at a steady pace. This form of activity was brought about because many bodybuilders have popularized the idea of fasted cardio. This is when you perform LISS on an empty stomach super early in the morning. This is thought to burn that stubborn body fat, because you haven’t eaten, and you are accumulating a ton of work. This can be effective as a means of burning more calories, however that doesn’t mean that it is superior.

HIIT (high intensity interval training) cardio is the exact opposite of LISS. This involves very short, intense intervals of exercise that jack your heart rate up and allow rest to help it get back to normal. This rise and fall of the heart rate are thought to make the body work harder, therefore burning more calories.

As you can see, these are two opposing ideas, so this is where the confusion comes in.

However, they both work!

Each one can be used to meet the ultimate goal of a caloric deficit. They both burn calories and it all depends on what you need and your preferences.

However, I would like to explore and see the pros and cons of both forms of cardio.


When one is doing this form of cardio, it can be done for a long time. It is at a low enough intensity that you can casually do it. This is why the idea is so attractive for most. Individuals can hop on the stair master for an hour and burn 100-200 calories. You have probably noticed that a ton of these machines have televisions on them. This is because the intensity can be so low that you can even watch your favorite show during it.

It is typically low impact which is a big plus of older individuals or people starting out overweight. It is a great step for beginners who are looking to burn some calories and get in shape.

It also has an added benefit of increasing your cardiovascular endurance. If you are someone who has trouble working out for a long time or doing physical activity for prolonged periods of time, this is a great way to get better.

One con to this form of exercise is that it is very time consuming. Depending on your goals, you may spend the majority of your time in the gym doing it. For busy people this is not going to be the best option for getting in a workout.

The second con is that due to LISS being very prolonged, while it does burn calories, it can start to take away from muscle mass. As we workout, if we continue going after we have exhausted our stores of energy, we will sometimes tap into our muscles to create more. If you have ever seen a marathon runner, they tend to not have much muscle. This is because they spend most of their time doing LISS. This is what we call a catabolic state, which starts breaking things down instead of building them up. One strategy for avoiding this, would be to utilize peri-workout nutrition. This could come in the form of consuming carbohydrates during your LISS, or even some BCAA’s (branched-chain amino acids).

Those are some of the benefits and cons of performing LISS, however, what really matters are your goals and your needs. Those will dictate what form of cardio is best for you.


HIIT has become very popular in the last decade. You can see it being done at the gym, for CrossFit, and even some bootcamps. This is for good reason. We live in a busy society. People want maximum results, in a very timely manner. While these may seem very counterintuitive, it can be done.

A HIIT workout utilizes short bursts of maximum or high effort, followed by a period of rest. This is repeated throughout the whole workout and really does a number on you. Weights are sometimes implemented, but it can be as light as body weight. As you do this form of cardio, your heart rate spikes, but you allow it to decrease during rest. This up and down of the heart rate really makes the body work harder. You may notice that you can get through a ton of LISS. However, that does not mean you will do as well for HIIT. The stimulus is completely different.

It has become popular, because it gives you a very high metabolic effect in a short time. Most of these workouts last under an hour and are perfect for people on the go. People are able to burn fat while saving time. Sounds perfect right?

HIIT also helps to preserve and even grow muscle mass. This is due to the fact that you are activating those fibers quickly and then letting them relax. This allows for recovery and for some of the body’s metabolites to replenish. It also is done faster. This helps to avoid that catabolic state that we mentioned earlier.

HIIT doesn’t have a ton of cons, but there are a few.

One being the intensity. Some people just aren’t conditioned or ready for that yet. If you have no previous experience with this type of workout, I do not recommend just jumping right in. So there is sometimes a barrier of entry when it comes to performing this sort of cardio. There are ways to scale this back and help people become adjusted, especially by having someone such as a trainer or coach to assist you.

The second is that you can only handle so much of it. Do not feel as if you need to do HIIT every day. The stimulus is a lot stronger, meaning that you don’t need as much of it. You wouldn’t take a stronger medicine every day just because you took the weaker one the same.

HIIT is a great option, but it isn’t always for everyone. Again, this is based on your needs.


To wrap things up, we discussed the pros and cons of both LISS and HIIT. We compared the two and as you can see, they are both useful. You can use either one, but it is really based on your preferences.

They both accomplish the goal of increasing your health and helping you lose body fat. This is done by adding to your calories burned which helps to create a caloric deficit. Having someone help you make this decision is crucial and could help you find what is going to best work for you.