Over the past few years, there’s been a major buzz around high-intensity fitness training. With dedicated HIIT studios springing up at a rapid rate in cities across the world, the trend shows no sign of slowing down anytime soon – especially with the advent of competitions like Hyrox where gym-goers can vie against each other in these ultra-tough workouts.

But if your gym schedule exclusively revolves around training that pushes you to max effort, you might be missing out on a crucial, lesser discussed part of any effective workout plan: Zone 2 training.

This slower-paced training method has recently gained a good deal of traction, thanks to fitness podcasts and Reddit forums, with experts claiming it offers some seriously impressive benefits.

The most appealing thing about hanging out in Zone 2? By dialling down some of your gym efforts, you could maximise your gains and improve your overall fitness level at the same time. Here’s why…

What is Zone 2 training?

Research has long told us that getting your heart rate up is essential to any healthy lifestyle. This type of movement, known as cardiovascular exercise, primarily works the heart, which is arguably the body’s most vital muscle.

The thing is, not all cardiovascular exercises are created equal. While a brisk lunchtime walk mildly elevates your heart rate, a round of rapid-fire burpees can send it soaring. This important distinction is why exercise physiologists have categorised five heart rate ‘zones,’ ranging from maximum effort and intensity (Zone 5) to the absolute minimum (Zone 1).

“Zone 2 training is one of the lowest efforts on the scale,” explains Steven Dick, director at the London personal training course provider The Fitness Group. “It refers to exercise at an intensity level where your heart rate is in the aerobic zone, which is typically between 60-70% of your maximum heart rate.”

Zone 2 training might sound technical, but chances are your already doing it. Good examples include brisk walking, hiking, jogging, moderate cycling, swimming, and paddleboarding – essentially any activity that you can comfortably perform while still holding a conversation.

What are the benefits of Zone 2 training?

Endurance athletes like cyclists, ironmen and marathon runners all have one thing in common: they all believe that Zone 2 training is key to performing well on race day.

Dick explains: “At Zone 2 and below the body is primarily burning off its reserves of fat for energy, while, at higher exercise intensities (such as Zones 3, 4, and 5), the body increasingly relies on carbohydrates (stored as glycogen in the muscles and liver) for energy production. This is because carbohydrates can be broken down more rapidly to provide the quick burst of energy needed for higher-intensity efforts.”

By training in Zone 2, where fat is the primary fuel source, Dick says that gym-goers can effectively enhance their fat metabolism, which improves their endurance levels and optimises their ability to use fat as a source of energy during longer-duration sessions.

Having superhuman levels of endurance is a no-brainer for distance runners and cyclists, but it shouldn’t be overlooked by everyone else in the gym either. Whether you’re into lifting weights, boxing, ballet, or rock climbing, building endurance is a must-have, as it allows for longer, more effective workouts, giving you time to focus on perfecting your skills.

“Introducing Zone 2 training into a well-rounded workout plan is also great for faster recovery between intense workouts, when compared to just regular sedentary rest days,” adds Dick. “Plus, it reduces the risk of burnout and overtraining in the long run, as it reduces the overall stress that intense exercising puts on your body, while still allowing you maintain a decent level of fitness.”

How can I try Zone 2 training?

“The easiest way to train in Zone 2 is by using a basic heart rate monitor during exercise,” says Dick. “With this method, you’ll need to keep an eye on the monitor during exercise to make sure your heart rate is falling within 60-70% of your maximum heart rate.”

To calculate your maximum heart rate, you can use the ‘220 Minus Age’ method, which involves simply subtracting your age from 220. For instance, if you’re 30 years old, your estimated HRmax would be 190 beats per minute. Around 115 beats would therefore be your Zone 2 sweet spot.

Helpfully though, many of today’s fitness watches offer smart features that will allow you to set a desired heart rate zone for your training, giving you a subtle nudge if you’re falling out of sync.

“It’s generally recommended to include Zone 2 training sessions two to four times per week, although it depends on what you are specifically trying to accomplish fitness-wise and the time that you can dedicate to it,” says Dick. “A beginner is best served with fewer sessions per week with more recovery time in between in order to acclimatise themselves to consistent fitness, whereas someone more familiar with exercise might want to push themselves a bit further.”

Why polarised training should be your new training goal

In fitness, there’s a term called the ‘dead zone’. This bleakly-named fitness pitfall happens when your effort falls short, and aren’t intense enough to deliver significant gains or performance improvements. Think: those regular low-energy days where you go to the gym and half-heartedly pump some dumbbells.

“Many people fall into this ‘dead zone’ of training,” says Dick, ““where they exercise at moderate intensities that don’t provide significant benefits in terms of either aerobic development or high-intensity performance.”

Instead of repeatedly hitting the gym at one effort level, Dick emphasises the effectiveness of polarised training, advocating for spending most of your time in either low-intensity (Zone 2) or high-intensity (interval) training. This tailored approach has been proven to yield better results than dwelling in the moderate intensity ‘dead zone’.

“By prioritising Zone 2 training for foundational fitness, and integrating high-intensity intervals for performance gains, you can optimise your training, especially if endurance sports like running or cycling are your thing,” says Dick.

To sidestep the ‘dead zone’ and maximise your workouts, Dick suggests crafting a routine that mixes various intensities and challenges. Whether it’s ramping up intensity with high-intensity sessions, engaging in strength training, or diversifying your workouts, the key is to keep your body adapting and progressing.

In fitness, it’s not just about constantly pushing yourself to the limit – embracing a balanced approach to training can bring sustainable progress that won’t leave you wincing after every workout.