What type of cardio is right for you?

Why is cardio always the hot topic of fitness discussion and seems to be the solution to burning fat? As we have all learned and have written in the past, that cardio is no longer the ultimate solution when it comes to changes in body composition. New times have come and we have tons of research studies showing that weight lifting is much more superior for fat loss and changes in body composition. But, even though we have these new findings, people still don’t get it and people still want to sit on bikes reading magazines about Kim Kardashian’s divorce for hours on end. Do what you want, but I know that I am one of those types of people who want to get the most for their money when it comes to training. This leads me to write about what type of cardio is right for you. I will make a comparison between HIIT cardio Vs LISS cardio, since these two forms of cardio are the most used. By the end of this article, you’ll have a very good idea of ​​what type of cardio is right for you and how to use it effectively.

What the heck do these crazy HIIT and LISS acronyms stand for? HIIT stands for High Intensity Interval Training, which consists of short sprint intervals coupled with low to moderate intensity work. An example of this would be a 30 second sprint followed by a 4 minute steady pace walk to cool down and normalize your heart rate and then repeat. LISS stands for Low Intensity Steady State Cardio, which is purely low to moderate intensity work. An example of this would be walking on the treadmill or riding a bike and being able to carry on a conversation (we tend to see a lot of this in gyms). Now that you have a basic understanding of the two forms, let’s dive into some more detailed things.

Why is testing lactate threshold (LT) and anaerobic threshold (AT) a good idea? The AT and LT are extremely powerful predictors of aerobic exercise (cardio) performance. There are 2 ways the muscle can burn glucose (sugar in the blood) and that is through aerobic work (with air) and anaerobic work (without air). For example, long lunges of LISS cardio are considered aerobic work and weight training or HIIT cardio can be classified as anaerobic work. The AT and LT are an excellent test for cardio HIIT and LIIS because they provide a great predictor of what type of work ATP (adenosine triphosphate) is producing. ATP is a quick burst of energy that we get in our muscles when we contract them (for example, every time you do a bicep curl, you get a quick burst of ATP). HIIT produces better changes in exercise capacity compared to LISS cardio. High intensity training will hit the AT and LT, that’s what causes the body to make metabolic changes. When you are doing LISS, you are considered below AT and LT. A simple test is being able to hold a conversation while doing cardio. When you do HIIT, you are above AT and LT, and when you are above AT and LT, you are looking for a greater improvement in metabolism, which leads to better fat loss over time.

How can you change your metabolism? (1) If you want to change your metabolism, you must increase muscle mass and increase the oxidative capacity of your muscle. Your muscles have these energy-producing units called ‘mitochondria’ and this is where ATP is made and fat is burned. The more mitochondria you have and the more active they are, the more oxidative capacity you have for fat loss. HIIT increases mitochondrial capacity and actually increases the number of mitochondria you produce.

Studies show that greater fat loss is obtained through high intensity training due to increased oxidative capacity. Whereas with LISS you are only burning calories right now, there is no 24 hour energy expenditure (increased metabolism) and it hurts later on because your body adapts and you end up needing more to lose fat. With HIIT you are burning calories right now, but you actually change the metabolism of your muscles and you increase your metabolism because you increase the mitochondria density of your muscle, so you increase the oxidative capacity of your muscles and you actually burn more calories. What most people don’t realize is that you have to put your body into an uncomfortable mode and use maximum energy expenditure. It’s supposed to hurt when you’re doing HIIT and if it hurts, you’re in an uncomfortable mode and that means you’re doing it right.

The body is very adaptable. (2) We usually see a lot of people doing hours and hours a week of LISS and according to the calculations they should be losing kilos, but they can’t lose anything because their metabolism adjusts to low intensity exercise. It just isn’t enough because it’s just a calorie burn at that point, not a 24-hour energy expenditure.

If you do LISS all the time, you’re basically trading calories and calories and you can cut these same calories through diet and still get the same effects. Example: You burn 200 calories in 30 minutes of LISS, you can cut 200 calories through carbs or fat and get the same effect instead of getting a 24 hour energy expenditure through HIIT cardio.

(3) A study by Wilson et al. From the University of Tampa, FL shows that when you add LISS you get a temporary boost in weight loss. The subjects lost a couple of pounds the first week and after that they lost nothing. This happened because their metabolism completely adjusted to that and that became their new set point of what they had to do to maintain themselves. LISS on a low calorie diet is terrible for fat loss and could cause muscle loss.

During a low calorie diet, LISS cardio is more catabolic (loss of muscle mass) towards muscle compared to HIIT cardio, which is much more muscle sparing. The reason is your metabolism is so set to LISS and you constantly have to do more and more and people don’t understand when you’re on a low calorie diet it usually ends up being low carb so once you run out glycogen (carbohydrates stored in muscle), your body is going to look for energy to rely on and guess what it does? Protein! Once it goes after protein, you start to see catabolism (loss of muscle mass).

(4) In the same study by Wilson et al. It showed that LISS caused more muscle loss than HIIT. HIIT caused more muscle retention because when you’re doing LISS (for example, walking at a fast pace) you’re not activating the muscles in the same way as if you were lifting weights. So when you run, you have hip flexion, knee extension, and these are all weightlifting movements. HIIT is another way to overload the muscle. Just compare the body composition of a sprinter to that of a marathon runner, plus muscle mass!

So it’s really hard to argue with this study because HIIT activates hip and knee movements. Hip flexion and knee extension are the same movements when performing leg exercises. Also, by doing high intensity work you are activating the muscle fibers and every time you activate the muscle fibers you are primed for growth. Unfortunately, LISS cannot stimulate muscle fibers in the same way.

(5) In another study by Naito et al. From Juntendo University in Japan, it was found that in rats, the satellite cell pool enhancement caused by resistance training is not influenced by the duration but by the intensity of the exercise.

So I know most of you are saying that it was done in rats, but rats are very good models for protein synthesis (production of new proteins in muscle tissue) and metabolism because they have similar responses to amino acids and your metabolism. Also, for those who don’t know about satellite cells, there is a need to increase the number of satellite cells in humans because it leads to the creation of new muscle fibers and the more muscle fibers you have, the more muscle growth will occur. So what’s interesting about this finding in this study is that when the rats did HIIT, they got muscle stimulation, and that’s because HIIT overloads the muscle. When the rats performed LISS, there was no activation in the satellite cell pool. So it shows that when it comes to cardio, intensity matters more than duration.

Now I know many of you have gotten the hint as to why HIIT cardio is more advantageous than LISS cardio for muscle retention and fat loss and it seems like I totally squashed LISS cardio. But note that this does not mean that LISS is useless. I am a big believer in doing HIIT and LISS combined. Here are the following reasons why:

– You can’t do HIIT 5-6 days a week because it will eventually negatively impact your weight training and interfere with growth.
– Many people have legitimate orthopedic, cardiac, and even psychological reasons to avoid HIIT, which is why LISS is your only option.
– HIIT could be dangerous if not used correctly and could lead to injury
– HIIT and LISS in a combined, cyclic or rotational way seems to be the best formula in my opinion

So sitting there and saying that HIIT is far superior to LISS for improving body composition is just as bad as saying that 6 reps per set is better than 20. I’m a firm believer that both HIIT and LISS cardio have unique benefits. themselves. I feel that both should be incorporated into their routines as each has specifically different effects. The bottom line is… Do the type of cardio you prefer. Whichever turns you on the most because you will most likely try harder. HIIT is faster, proves more effective for fat loss, creates metabolic changes, and helps with muscle retention, but not everyone can do HIIT. LISS is safer, but it takes twice as long to accomplish similar things and still has its place for fat loss in moderate amounts, from a pure calorie burning standpoint (i.e. just to burn calories and not make changes to your metabolism).

My intentions were not to favor one form of cardio and criticize the other, even though it sounded like that. My intent was to educate and notify you that times have changed and science is showing some good things with HIIT cardio. But at the end of the day, it’s up to you which type of cardio is best for you. Hopefully, after reading this article, you should have a pretty good idea of ​​what type of cardio is right for you and how to use it effectively. If you’re still confused… JUST DO IT! Peace!