HIIT vs LISS: Which Is Better for Fat Loss?

HIIT and LISS are two very common types of workouts! I include both of them in my workout plans and in my own daily life. :)

But these 2 types of workouts impact your body in different ways. It’s important to know how they work so that you can train in the best possible way for your body and goals!

In this blog post, I’ll explain more about how they work and how they can help you lose weight and burn fat.

WHAT IS HIIT?

HIIT stands for high-intensity interval training. HIIT workouts are a type of circuit training in which you alternate between performing intense moves (like sprinting) and more mellow moves (like walking) to give your body a rest. You’ll be sweating a lot by the end!

Most HIIT workouts are just 10 to 30 minutes long. Remember, these workouts are pretty challenging, so most people couldn’t handle a HIIT workout that lasts much longer than half an hour.

This back-and-forth between extreme and low intensity can be really good for your body. Some of the best benefits of HIIT are:

• Burns a lot of calories in a short amount of time.
• Boosts your metabolism, which leads to calorie burn even after the workout is complete.
• Doing HIIT improves your cardiovascular system, which can help your body be more efficient at burning fat (more on this later!).
• HIIT workouts are convenient! They’re short and you can do them almost anywhere, including a hotel room or your living room.

However, HIIT isn’t something I recommend you do all the time, for several reasons.

• Too much HIIT is stressful on your body. This stress can raise your cortisol levels, which can lead to weight gain.
• HIIT workouts are often very focused on the lower body. Most of them involve exercises like squats, burpees, or sprinting. 2 out of 3 female body types will notice that this makes their lower body bulkier than they would prefer. :)
• Your body needs variety and time to recover between HIIT workouts.

WHAT IS LISS?

LISS stands for low-intensity steady state cardio. As you can probably already see from its name, LISS cardio is very different than HIIT. LISS is any type of cardio in which you maintain an even and low pace for a set amount of time.

Some examples of LISS include:

• Power walking (one of my favourite types of exercise!)
• Going for a hike
• Cycling at a steady pace
• Swimming at a steady pace

LISS technically is a walk in the park, but that doesn’t mean it is easy. :) It’s totally doable and you should be able to exercise for about an hour, but you should still feel your body working.

LISS might not be as challenging as HIIT, but it is still very important to include in a successful fitness routine. :)

Here are some of the reasons LISS is important:

• LISS is a great way to get into exercise! If you haven’t worked out in a while, a HIIT workout might feel impossible. LISS workouts will be doable for you!
• You can do LISS anywhere! Can you take a walk? If yes, you can do LISS!
• LISS is perfect for recovery. If you’ve recently done a hard HIIT workout or a tough session of resistance training, your body might need a break. LISS is a good way to stay active without overdoing it.
• Your body burns a lot of fat during LISS workouts. I’ll explain more about this later!

WHICH IS THE BEST FOR WEIGHT LOSS?

Both HIIT and LISS are super important for weight loss! But your body responds differently to LISS workouts versus HIIT workouts. They play different roles in helping you lose weight. Here’s how:

LISS BURNS FAT!

Your body needs energy. (Obviously!) And one of the amazing things that the human body does is that it converts the carbohydrates and fat we eat into energy.

Most of the time, your body uses a combination of both carbs and fat for energy. But, depending on the type of workout you do, it will choose to burn mostly fat or mostly carbs.

When do you LISS, you aren’t working out too hard. Your body is still getting plenty of oxygen, and it is more efficient for your body to use fat instead of carbohydrates for energy.

Harder workouts (like HIIT) make it harder for your body to get oxygen. So, your body opts to use carbs as a quick energy source instead of fat. LISS workouts, then, are great because they keep your body in the fat-burning zone.

If this is confusing, no worries! I have a very detailed blog post about how the fat-burning zone works. If you want to understand the zones in more depth, give it a read. :)

Otherwise, just remember this: LISS workouts keep your body in the ideal zone for fat burning. When you take a long walk or do other forms of low, steady-state cardio, your body chooses to use fat instead of carbs!

This is one of the reasons why walking is so wonderful at slimming down legs. It helps you burn fat!

HIIT INCREASES FITNESS LEVELS

HIIT workouts don’t keep your body in the fat burning zone. They mostly burn carbs. So why bother doing HIIT workouts?

Well, besides burning lots of calories and boosting your metabolism, HIIT also makes your heart stronger. HIIT improves your cardiovascular system, which helps you become fitter.

Doing HIIT workouts also boosts your anaerobic threshold, meaning that you’ll be able to stay in the fat-burning (or aerobic) zone for longer.

WHY IMPROVING FITNESS MATTERS FOR FAT LOSS

Think about it like this: We all know that going for an hour-long walk will burn more calories than a 20-minute walk will. We also know that walking at a faster pace for 30 minutes burns more calories than walking at a slow pace for 30 minutes.

The harder or longer you push yourself, the more calories you will burn.

And we also know that the fitter you are, the easier it is for you to do longer, harder exercises.

So, this means that a person who is fitter can stay in the fat-burning zone for longer while also doing exercises that burn more calories.

HIIT helps you become more fit. The fitter you are, the more your body will be able to rely on fat for energy, and not carbs.

JUST DON’T STRESS YOUR BODY OUT!

One thing to remember about doing HIIT is to pay attention to your stress levels. HIIT workouts can increase cortisol in your body. Cortisol is your stress hormone, and it can lead to weight gain!

Some women see that HIIT burns a lot of calories. They want to lose weight, so they do too much HIIT. Unfortunately, overdoing HIIT can actually have the opposite effect: it can cause you to gain weight, especially in the love handle area.

In my experience, stress can be a major hindrance to weight loss! It took me time to figure out, which is why I’m so vocal about sharing this information with women. If you haven’t read my story about hormones and weight loss, feel free to read it in this blog post. :)

Also, doing lots of HIIT can cause you to build a lot of muscle in your lower body. This means your legs will actually get bigger instead of smaller.

This is why I don’t recommend doing HIIT more than once or twice a week.

BOTH BURN CALORIES

HIIT workouts help you burn a lot of calories in a short amount of time. That’s one of the reasons I love HIIT. It’s efficient!

But you can still burn a lot of calories doing LISS. It might take you longer, but it is easier on your body. You can do longer sessions of LISS than HIIT and still get that sweet calorie burn.

Because both HIIT and LISS burn calories, they can both help with weight loss!

FOR BEST RESULTS, COMBINE HIIT AND LISS

The best way to lose weight is to combine low and high-intensity cardio. :)

If your goal is fat loss, I suggest doing LISS 5-6 times a week and 1-2 HIIT workouts a week.

Both LISS and HIIT can play super important rules in your fitness journey! Make sure you check out my 8-week lean legs program if you’re wanting more in-depth workout plans to help you lose fat. :)

And as always, if you have any questions, feel free to ask! xx

Love Rachael