When it comes to exercise, my aim is usually to get the most out of each workout, pushing myself to my max. No gain without pain, right? But maybe that isn’t always the case.
In the past few years, low-intensity steady-state (LISS) cardio has been growing in popularity as a way to lose weight. One example is the TikTok “12-30-3” workout trend, where you walk up a 12 per cent incline for 30 minutes at 3 mph (4.8 kilometres per hour). This type of exercise involves slower aerobic activity over an extended duration, such as walking or cycling at a pace comfortable enough to maintain a conversation, but brisk enough that you feel a tad out of breath.
This is in contrast to high-intensity interval training (HIIT), when you do exercises such as jump squats at near-maximum capacity in repeated intervals of up to a minute, with short rests in between. You should aim to hit 80 to 95 per cent of your maximum heart rate during HIIT. The goal with LISS is to be at around 50 to 65 per cent of your maximum for about 45 minutes to an hour. At this intensity, your body is burning mostly fat for energy. Anything more vigorous and it switches to using mainly carbs.
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Proponents of LISS say this means it is better than other exercises at decreasing body fat. But that isn’t borne out by the research: a found no difference in fat loss between people who did interval training and those who did LISS, while one in found LISS also isn’t any better for improving cardiovascular fitness.
However, LISS does have some advantages. For one, it puts less strain on the body thanks to its lower intensity, allowing you to recuperate more quickly and thus squeeze more workouts into your week, as you don’t have to wait as long for your muscles to recover. That 2024 review also found that the more workouts you do a week, the greater the boost to your aerobic capacity. So, if you only have the energy for one or two high-intensity sessions a week versus four or five bouts of LISS, you may want to opt for the latter.
, when our bodies break down glucose for energy, producing lactic acid in the process. This then separates into lactate and protons. The former can hinder the ability of muscles to contract, while the latter impair muscle function, leading to muscle fatigue. As LISS promotes blood flow to skeletal muscles, it helps , speeding up recovery. So it can be beneficial to cap off an intense workout with a little LISS, like walking on a treadmill at an incline for 15 minutes, or going on a leisurely hour-long bike ride on active recovery days.
As for me, I am going to find the time to make LISS a priority. A long stroll in the park doesn’t sound too bad, even on a rest day.
Grace Wade is a health reporter for 91av based in the US
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