What Is LISS? Everything You Need to Know About the Low-Impact Workout Trend

When it comes to working out, slow and steady (LISS) versus fast and sweaty (HIIT) has long been debated. From weight loss to recovery, here’s how a change of pace might work for you.

Not every workout needs to be a sweat-soaked, high-speed circuit. That’s just exhausting. Sometimes, it pays to slow things down, especially if we’re working out multiple days in a row.

This is where LISS can help. With a focus on sustainable, low-impact workouts, it’s more than earned its place in your fitness arsenal.

What does LISS stand for?

Confused by all of these fitness acronyms? Let's break it down.

“LISS stands for Low Intensity Steady State and is a form of cardio exercise,” explains Faisal Abdalla, coach for audio-led fitness app WithU. LISS training is basically anything where you can still hold conversation, like walking, jogging, swimming or cycling at an easy pace.

“LISS often gets referred to as the opposite of HIIT training (High Intensity Interval Training) where you’re pushing yourself hard for short bursts of time and taking rest periods in between,” adds Abdalla. “The point of LISS training is to engage in exercise for a long period of time where you're not at your maximum effort or heart rate, allowing you to go on for longer without getting fatigued.”

What are the benefits of LISS training?

“There are numerous fitness and health benefits associated with LISS Training,” says Farren Morgan, founder of The Tactical Athlete.

To begin with, a study published in The Annals of Physiological Anthropology found that patients suffering from hypertension who regularly engaged in low intensity training performed at 50% VO2max or lactate threshold (both indicators of overall exertion) reduced their blood pressure with three to five 60 minute sessions per week.

The same patients also improved their cardiovascular fitness and stamina, with the study suggesting LISS can be an “easier and safer” way of promoting health, especially among older or overweight people. “If you haven’t exercised recently, LISS training is a highly effective solution for developing your foundational fitness without straining your body,” Morgan adds.

Unlike HIIT workouts, LISS is a low-impact option which puts less strain on your joints. “This makes LISS a great starting point for beginners or those dealing with injuries,” adds Abdalla. “Your recovery will also be better from LISS training than your recovery from HIIT as it places less strain on your body.”

Amusingly, a 2015 study comparing HIIT with LISS concluded that participants found Tabata (a form of high intensity exercise) “less enjoyable” than steady state workouts. However, the study authors also note that “perhaps variety in the type of exercise is as important as the type of exercise per se”.

Is LISS good for weight loss?

“LISS is great for weight loss,” says Abdalla. “By performing any type of LISS cardio, you will burn calories which helps you achieve the calorie deficit you need to lose weight.” What’s more, Abdalla says that LISS can help our bodies use stored fat as fuel, instead of the glycogen stored in our muscles.

For best results, you shouldn’t depend on LISS alone. “LISS training is an effective weight loss tool, especially when you combine it with a proper diet and a healthy lifestyle with at least seven hours of sleep,” Morgan says. This is backed up by a 2014 study which noted that “Randomized clinical trials show that exercise produces moderate weight loss, particularly as an adjunct to dieting.”

Is HIIT or LISS better for fat loss?

Should you swap your running shoes for the battle ropes? Well, a clinical study in the Journal of Obesity found that LISS was more effective than HIIT at improving “fat distribution”, but what about overall fat loss?

“If we focus solely on training, HIIT workouts burn more calories per minute because of the heightened intensity of their workouts, allowing you to achieve significant results within shorter timeframes,” says Morgan.

There is a caveat. “It is crucial to note that someone who opts for LISS training, has a healthy lifestyle and maintains a caloric deficit may still have a higher likelihood of losing fat faster than someone that incorporates HIIT workouts but does not prioritize their fitness beyond the gym,” says Morgan.

“LISS is better for fat loss because it provides more oxygen, and the body needs oxygen to metabolise fat," argues Abdalla, while noting that HIIT is a good alternative if you’re short on time.

Meanwhile, a 2021 meta-analysis looking at HIIT versus LISS concluded that “the patterns of intensity of effort and duration during endurance exercise has minimal influence on longitudinal changes in fat mass,” noting that HIIT requires more energy, but less time, meaning the choice ultimately comes down to an individual’s lifestyle needs.

Does LISS cause muscle loss?

It’s a common fear among gym-heads that steady-state exercise (especially in the form of running) will burn muscle mass for fuel. Morgan says it isn’t true. “LISS helps to preserve muscle mass by promoting blood flow to your muscles to aid in their repair and recovery,” he says. It does this “without placing significant stress on your body, making it an effective solution for those that want to burn their body fat while conserving their muscle mass.”

In other words, it’s the ideal workout, as long as you’re fuelling yourself properly. “LISS combined with a very low calorie diet can lead to muscle loss,” warns Abdalla. “HIIT can be more muscle sparing, so it’s a better option if you’re on a low calorie diet.”

What is the best form of LISS?

“When LISS training, you should aim to keep your heart rate elevated within a comfortable range, usually around 50-65% of your maximum heart rate,” says Morgan.

As always, you should adapt your cardio routine based on your preferences, fitness level, and overall goals to create a regimen that fits your needs.

Here, Abdalla and Morgan analyse the most common forms of LISS, and their benefits.

Walking

“In my opinion this is the best form of LISS training,” says Abdalla. “Walking is often a great fat burner, because there is more oxygen available compared to when you’re sprinting.”

Pros: Anyone can do it, and it doesn’t require money or gym equipment. “Getting those extra steps in every day is a great starting point to weight loss and being fitter overall,” says Abdalla.

Cons: Walking takes ages. Depending on factors like your fitness levels and weight, you might burn 300-400 calories in 10,000 steps.

Jogging

One of the simplest forms of LISS requires little more than a pair of running shoes, and the open road.

Pros: Cost-effective. Can also be combined with HIIT to improve pace, stamina and endurance.

Cons: “Jogging isn’t accessible to everyone, plus it can be extremely fatiguing and lead to injury if done without mobility sessions,” warns Abdalla.

Rowing

Like jogging, rowing can be done at your own pace. And like jogging, it’s also a bit repetitive…

Pros: Strengthens muscles across the body, great at burning calories.

Cons: Requires a gym membership, or your own rowing machine. Can be monotonous.

Cycling

“Cycling is another effective method of LISS training because of its low impact on the joints,” says Morgan.

Pros: Enables you to engage in activity for long periods of time at a steady rate. You can also do it in all weather conditions, be that outside or in the gym.

Cons: Not everybody has a bike, there’s a big time commitment for a long ride, and it can be very expensive when you start buying all the gear.

Swimming

“Swimming at a gentle pace is very beneficial for those who have sustained injury and are looking for a low impact form of exercise,” says Abdalla.

Pros: “Swimming is another highly effective method of LISS training that essentially has low to no impact and is pain and resistance-free,” says Morgan. Switching your strokes can train different muscle groups, too.

Cons: Your technique needs to be on point for maximum benefit.