LISS vs HIIT for Fat Loss: Which is Better?

Whatever fitness level you’re at, it’s likely that you’ve compared LISS vs HIIT when trying to decide the best way to lose weight.

Both cardio training, each one provides various different benefits to your fitness – and cutting those stubborn pounds.

But which one is the best? Which one will get you leaner, quicker? Which one could get you looking like a pro the easiest?

It can be confusing. That’s why we’ve done the legwork to answer the LISS vs HIIT question once and for all – and help you determine which one will be the most effective for you. Before we answer the question – LISS vs HIIT for fat loss: which is better? We need to define what each workout style is so you can have a deeper understanding before we go into which is better for fat loss.

What is LISS?

LISS cardio stands for low-intensity steady-state cardio. It’s often associated with exercises like cycling, jogging, swimming or walking as it requires you to perform the same exercise for more than 30 minutes at a steady rate.

The key to LISS cardio is to maintain the same energy for the whole workout at the same pace throughout. This lower intensity training means you use fat as your main fuel source, rather than glycogen stores, which are saved for more high intensity workouts. This helps train your body into using fat for fuel[1].

What is HIIT?

Popular HIIT training is what you’ll probably know as sprinting or circuits. HIIT stands for high-intensity interval training which literally means performing intense exercises in short bursts. Unlike LISS, HIIT workouts take less time – between 5 and 20 minutes usually.

The idea is that you push yourself to the max during the short interval and then have a lower intensity resting period before returning to pushing yourself to the limit again. This pattern is repeated until you finish your workout.

HIIT works by creating an oxygen debt to your muscles, so your body has to burn fat for energy instead. This means, you could be burning fat hours after your workout to make up for the reduced oxygen[2].

What are the benefits of LISS cardio?

When doing LISS cardio, your aim is to keep your heart rate low – at around 50 – 65% of your maximum heart rate[3]. The best way to work out your maximum heart rate is to subtract your age from 220[4].

So, say if you were 25 years old and you wanted to work out your optimum heart rate for doing LISS cardio it would be:

Maximum heart rate: 220 – 25 (age) = 195

LISS heart rate: 195/100 x 65 = 126

As with most aerobic exercise, LISS cardio can help improve blood flow, reduce stress[5], enhance cognitive performance[6] and lower the risk of heart disease[7].

LISS also has many other benefits.

Firstly, it’s suitable for anyone – whatever fitness level you are. So, if you’re just starting out on your fitness journey, you may want to use LISS as a way of building your fitness levels up in a safe and gentler way than more intense alternatives.

It’s also a great way to train for endurance events as it puts less stress on your heart and lungs so your body can build up endurance safely. In the same respect, because it puts less stress on your body, recovery time could be shortened too. People often use LISS as a recovery session after doing intense training like HIIT as it gives your body that chance to recover from the stress your body has endured.

Finally, studies show that LISS can help with fat loss[8], with the subjects in one study seeing a reduction in fat percentage[9] more than HIIT. This is down to it improving your body’s ability to use fat as fuel instead of using glycogen which is stored in your muscles[10].

There’s also evidence to suggest that LISS is more effective than HIIT for weight loss for certain people. Some research suggests that HIIT can leave beginners or less fit people feeling low in mood and confidence, meaning they’re much less likely to keep up the workouts than if they were doing lower intensity exercise[11].

In this way, LISS could work better for fat loss in the long run for people not keen on HIIT.

LISS vs HIIT for fat loss

What are the benefits of HIIT?


Unlike LISS, HIIT requires you to keep your heart rate at around 80 – 95% of your maximum heart rate when doing your period of intense training, then around 40-50%[12] during the recovery in between.

  • Better fat burn

One of the key benefits to HIIT is that you can pack in a fat-burning workout in much less time that LISS. As we mentioned before, sometimes HIIT sessions can be as little as 5-10 minutes, saving you time if you’ve got a busy schedule but want all the fat loss benefits. One study found that HIIT burned 25-30% more calories than 30 minutes completing other forms of exercise[13] like weight training, running or cycling.

  • Metabolism boost

Another benefit to fat loss that HIIT can provide is that it raises your metabolism for sometimes hours after exercise, with studies showing a two-minute HIIT workout of sprints increased the metabolic rate for 24 hours after[14]. Subjects who made no changes to their diet, but took up HIIT three times a week for 20 minutes per session lost over 4 pounds in 12 weeks[15].

Other benefits include reduced blood pressure[16] and blood sugar[17], alongside increased muscle mass[18] and cardiovascular fitness[19].

Drawbacks to LISS

In terms of LISS vs HIIT, there are a few drawbacks to LISS which may make you more likely to choose HIIT instead.

These include:

  • Long training sessions – because the idea is to keep your heart rate lower, you will need to do longer training sessions to achieve the same amount of fat burning as HIIT. If you don’t have time on your hands, HIIT may be a more efficient way to lose weight quicker.
  • May lead to boredom – sitting on a bike for 45-60 minutes can get repetitive – and many people might lose interest. One way to counteract this would be to take a book or device to watch a TV show. But make sure you don’t get too distracted and keep your heart rate at the right level throughout.
  • Could lead to injuries caused by repetition – doing the same exercise like jogging or walking day in, day out could cause repetitive injuries. So, try to keep your workouts fresh, doing a series of different LISS exercises throughout the week, alternating to avoid straining one or more muscle groups too much.

Drawbacks to HIIT

Like LISS, HIIT also has its disadvantages.

  • Could cause injury – if you push yourself too hard, you may end up going too far and injuring yourself. The key is to monitor how your body feels throughout, alongside your heart rate to make sure you’re doing your HIIT workout safely.
  • Can put stress on your heart and body – HIIT helps signal cortisol in your body – which is essentially the stress hormone that determines our ‘fight or flight’ responses. Whilst this can be beneficial for helping our body to grow in workouts, too much can cause lasting anxiety. So, make sure you are being reasonable and safe with HIIT, keeping it to 3-4 times a week and no longer than 30 minutes per session.
  • May affect your sleep – because HIIT gets your metabolism hiked and adrenaline turned right up, HIIT may not be the best training to do close to bedtime as you may still feel energized for hours after. Make sure you assess your body and how it responds to HIIT during morning workouts until you have got used to when your body returns to a normal state after.
  • Could lead to burning out – if you go too hard, too fast for a few weeks, the chances are your body will hit a wall. Motivation to keep up such intense workouts won’t last forever – and could be really difficult to maintain. Eventually, you may put yourself off – which won’t do your fat burning any favors. So, keep your workouts realistic and enjoyable for long-term weight loss.

How to get started with LISS cardio

Getting started with LISS is really simple. All you need to do is find low-intensity exercises you enjoy – whether that be in the gym or in the great outdoors.


  • Fast-paced walking
  • Cycling
  • Swimming
  • Jogging
  • Rowing
  • Cross-training

For beginners, you may want to start with 3-4, 45-60 minute sessions of LISS a week. For more advanced fitness levels, mix in LISS sessions with HIIT throughout the week.

LISS vs HIIT for fat loss

How to get started with HIIT

HIIT training requires you to go as fast as you can for around 30 seconds during one exercise, followed by 2-4 minutes of the same exercise at a slower pace/resting completely.

For instance, if you are on a stationary bike, pedal as fast as you can for 30 minutes, followed by an easy pace for 2-4 minutes. If you’re doing floor work like squat jumps, do as many as you can for 30-90 seconds before walking it off for 30-90 seconds. Each pattern should be repeated for 10-20 minutes.

The best HIIT exercises include:

  • Squat jumps
  • Burpees
  • Cycling
  • Sprinting
  • High knees
  • Jumping jacks

If you want to keep it interesting, why not create your own circuit which combines a number of HIIT exercises where you’d repeat the entire session over and over until the 20 minutes is up.

Want to keep energy fired up and cut those stubborn pounds faster? We recommend Instant Knockout Cut as the ideal training partner to help elevate your metabolism, boost endurance and keep calories controlled for quicker fat shedding.

The bottom line

All in all, HIIT vs LISS in terms of fat loss seems to be a draw. Both exercise techniques are proven fat burners and will help you lose weight if done correctly.

The question really is what style works for you. If you’re not prepared – or are too busy – to spend hours in the gym every week, HIIT training offers an effective way to burn high calories in minutes, so this may be for you.

However, if you’re new to fitness or put off by the intensity levels required to make HIIT work, LISS is a gentler way to cut those pounds – and keep them off.

Combining the two techniques is also a great way to keep your workouts exciting – and burn fat fast.

Whatever you decide to do, commitment is key to shedding those stubborn pounds. So, choose the workout that you’re most likely to stick to and watch those calories melt away.