HIIT vs LISS: Which is better?

HIIT and LISS cardio have 3 key differences. These differences will determine which one is better for you to get the results you want.

HIIT vs LISS: Which is better?
Photo by Chase Kinney / Unsplash
7 min. read 2/10/2022, 11:14 PM

We all know that there are no quick fixes to fat loss. It's a long process that involves a combination of eating a healthy diet, strength training, and cardio. But when fat loss is the main focus, the first thing most people do is increase the amount of cardio sessions in their workout routine. That's because some workouts are more efficient at burning fat than others - Cardio is one of them.

Cardio is probably one of the most dreaded types of exercises, so it would be a real shame if all that sweat and hard work you're putting in is getting you nowhere... There are two types of cardio and one might be better for your goals than the other. The two types are: low intensity steady state (LISS) and high intensity interval training (HIIT). Understanding the differences between these two will help you figure out which best fits your lifestyle and your goals in order for you to get more effective results! Who knows maybe a combination of both is best... But you won't know until you know the benefits of each type so let's get started!

HIIT vs LISS

As we all know, cardiovascular exercises work the heart and circulatory system, and generate increased blood flow throughout the body to sustain movement. Essentially they increase your heart rate, help you burn calories, and work up a sweat! But not all cardio is created equal... So what is HIIT and LISS? And what are their benefits?

High Intensity Interval Training

Popularly known as HIIT, is a form of training that involves performing short bursts of high-intensity exercises performed at up to 95% of your max heart rate followed by lower effort rest intervals. Most HIIT workouts are done in 15-20 minutes because the structure of these workouts involve pushing yourself as hard as you can during each set with minimal rest inbetween.

These workouts are similar to circuit training. It involves selecting 5-10 different exercises, typically cardio exercises that target different muscle groups, performing them for 45 seconds to a minute and then repeating the sequence 3-4 times. Common HIIT cardio exercises are sprinting, burpees, jumping squats, mountain climbers, push-ups, high knees, kettlebell swings, and so many more. Pretty much any type of exercise can be put together for a HIIT session, the key is pick exercises that you can perform with good form and give it all your effort in a short period of time. So why would anyone put themselves through these intense, sweaty workouts? Well it has to do with the wonderful benefits...

Benefits of HIIT Workouts:

  • Fast and convenient: HIIT sessions are convenient for busy people who don't have an hour to get a workout in. They can be done in less than 30 minutes and require little to no equipment. Some like to include equipment like a jump rope, resistance bands, or free weights, but it's not needed. HIIT usually involves just a combination of bodyweight exercises that can be done anywhere and by all fitness levels!
  • Increases your metabolic rate for hours: HIIT workouts not only burn a lot of calories in a short time period, it also helps you burn calories hours after you're done! Studies have shown that it increases your metabolic rate for hours after exercise. [1]
  • Effective for fat loss: Despite the workouts being short, HIIT has been found to be effective at decreasing body fat. That's due to the body's recovery process called excess post-exercise oxygen consumption, or EPOC. After the workout the body taps into fat stores for the energy required to restore it to its normal resting state. [2]
  • Can help increase (or maintain) muscle mass: HIIT can help increase muscle mass for those who are new to working out or don't partake in weight training. Where you build muscle depends on the exercises being performed, so you'll mostly see a gain in the muscles primarily being used (mostly legs and core). Weight training is still the best way to build muscle, but HIIT is a good starting point for beginners to start promoting small amounts of muscle growth.

Low Intensity Steady State

Also known as LISS, is the most common form of cardio. Opposed to short bursts and high effort, this training involves one movement for long periods of time while maintaining a moderate heart rate (usually around 40-60% of your max heart rate). Due to its lower intensity, it requires little to no rest periods and is usually performed in 30-60 minutes.

This type of cardio has been around for decades, a few examples of popular LISS exercises are walking, running, cycling, swimming, hiking, or using cardio equipment like the treadmill or elliptical. The key is to go at a moderate, steady pace for an extended time period.

​Benefits of LISS workouts:

  • Aids in fat burning: Just like HIIT, steady-state cardio also improves the body's ability to use fat as fuel instead of the glycogen stored in your muscles. This happens because fat needs oxygen in order to be broken down and with lower intensity cardio more oxygen is available to your body. So the more oxygen you give your body, the more fat you are able to burn.
  • Easier recovery: LISS cardio is easier on the body and heart, which makes it great for all fitness levels, but also for better recovery. Less stress on the body equals easier recovery.
  • Good for training for endurance events: Those training for marathons, triathlons, or any sporting events use LISS as an effective way to prepare because it puts less of a stress on the heart and lungs than high intensity workouts.
  • Great cooldown/recovery after intense training: LISS is good to do as a recovery session. It's often done on active rest days or right after weight training.

Which one is the winner?

Well, that depends on you! Take into account the benefits, the differences, and see what fits your goals and lifestyle best. To help even further, let's go through the three main differences between these cardio workouts..

  1. Intensity
  2. Duration
  3. Amount of calories burned

The first two are easily understood - HIIT is higher intensity for a short time period, LISS is lower intensity at a steady, longer pace. The last one, amount of calories burned, is where the big difference lies and it might sway your decision to do one more than the other...

Most people believe since LISS cardio involves a longer duration, it will burn more calories. Although that may be true, it's not. Research shows that you can burn more calories doing HIIT than spending the same amount of time doing LISS. [3] That has to do with what we discussed earlier about how HIIT increases your metabolic rate and EPOC. After high-intensity workouts, like HIIT, your body needs more oxygen to restore it back to its resting state. So your body is hard at work replenishing energy stores, regulating hormones, and repairing muscles which leads to the continuing of burning calories hours after you've finished. Although you can burn 500-600 calories during an hour long LISS cardio session, and only 200 during a quick HIIT training session, your body will continue burning calories at a rate of 50 calories an hour. This can lead to burning a total of 700-800 calories, all from a 15-30 minute workout sesh! [4]

If your goal is weight loss and to burn fat then HIIT might be the most effective way to get results. But don't get it twisted, LISS is still a very effective way to lose weight and it's also less stressful on the body making it a great workout for recovery periods. It all depends on what you can do on certain days, if you have less time combine your lifting session with a quick HIIT workout, if you have more time consider doing a LISS workout after your lifting session. At the end of the day, the best exercise program includes a variety of workouts - LISS, HIIT, strength training, and flexibility and mobility work.