Heart rate training 101: Your guide to heart rate zones

There's an old saying: 'If it ain't broke, don't fix it'. When it comes to exercise, we often find ourselves sticking to the same routine or training plan. While there's nothing wrong with finding a workout you actually enjoy (we're looking at you, spin class fanatics), how do you know you're getting the most out of your training sessions?

Trainers and health professionals have the answer: checking in on your exercise intensity.

Everybody's ability is different — what feels like full throttle for one person might feel like a gentle stroll for someone else. But the science is clear: using heart rate to your advantage can help you reach your fitness or weight loss goals [1].

So how do you figure out the right training intensity for your body? Welcome to heart rate training zones. Let's break down how they work — it's easier than it sounds and will get you results a whole lot faster.

What is heart rate training?

Heart rate training is the process of using different heart rate zones to maximise your workouts. It means aiming to keep your heart rate within a set range (of heartbeats per minute) while you exercise, which can help you monitor how hard you're training [1].

Heart rate training enables you to get more bang for your buck — by helping you figure out the right intensity levels when you exercise.

Each heart rate zone represents a percentage of your maximum heart rate that we should be aiming for when doing a moderate or high-intensity workout. The ideal maximum heart rate will vary for everyone depending on age, health, medications, and many other factors [2].

Most health professionals recommend that we do about 150 minutes of moderate-intensity physical activity per week. For higher-intensity exercise, the guidelines suggest about 75 minutes per week [3].

This doesn't mean smashing everything out on a Monday though (yuck!), or trying to become an elite athlete overnight. Experts also suggest making sure you spread this activity out evenly throughout the week (or at least 4-5 days of the week). These guidelines will differ depending on your overall health and circumstances — for example, there are specific guidelines tailored to pregnant people, or disabled people [3].

According to the Heart Foundation, your target heart rate for moderate-intensity exercise should be around 50-70% of your max heart rate. For high-intensity training or 'vigorous' activity, you should be aiming for about 70-85% of your maximum heart rate [4].

Before we give you the rundown on how to use heart rate zones to your advantage, let's talk about why it's worth it.

What are the benefits of heart rate training?

There's no question that being physically active is good for us — no matter how much we'd rather stay on the couch sometimes. What we don't talk about as often, is how choosing the right exercise intensity can have even more health benefits than our regular routines [5].

Moderate-intensity exercise has been proven to reduce our risk of cardiovascular disease, but for men, the research has slightly different results — there are some studies that show men might need more vigorous exercise to keep their hearts healthy [5].

Studies also show that 1 tough workout or vigorous session a week could prevent cardiovascular disease in both men and women (when compared to those with low or no activity levels).

As we recover from the height of the COVID-19 pandemic, when a lot of us weren't as active as we'd usually be, the research offers some relief: by exercising at different intensities throughout your week, you can reverse the negative side effects of inactivity [5].

And the benefits don't end there:

Faster heart rate recovery after your workout

Research indicates that the slower your heart gets back to its resting heart rate after exercise, the worse this is for your health. A slower heart rate recovery after exercising has been closely linked to things like cardiovascular disease and coronary artery disease [6].

The same studies suggest that by exercising using heart rate zones, your heart rate recovery time and general endurance can improve. This also means a much healthier cardiovascular system!

Reduced risk of injury or overtraining

By tailoring your regime to your own heart rate training zones, you can reduce the risk of accidentally harming yourself during a workout.

Knowing what your maximum intensity or heart rate should be lets you know how hard you should be pushing yourself — and when to slow down. You also reduce the risk of fatigue or overtraining [1]. Better to know your limits than to go too hard and regret it later.

Increased endurance and aerobic fitness

Here's a little tidbit for you: part of your heart's job is to help transport oxygen around your body, delivering it to your muscles via the bloodstream. How well the body does this is referred to as your aerobic fitness level [7].

By doing heart rate training, you can increase your aerobic fitness — your heart learns to pump more blood with every beat [7]. You can also achieve a lower resting heart rate, and improve your overall heart health [5].

What are the different heart rate zones?

We know how paying attention to heart rate zones can help you train effectively, but what actually are the rate zones we're talking about? Let's dig in.

Zone 1

The first zone is a low-intensity zone, where you should focus on your warm-ups or cool-downs. When you're in zone 1, you should be operating at about 50-60% of your maximum heart rate (hr max) [8].

Zone 2

This one is slightly more intense, where you start turning up the heat a little. In zone 2, you should be at about 60-70% of your hr max. Zone 2 is where most people start with aerobic fitness exercises [8].

Zone 3

Again we turn up the intensity with zone 3, where you should be reaching about 70-80% of your hr max. Training in this zone can help to build endurance [8].

Zone 4

Zone 4 is where anaerobic exercise comes into play — a higher-intensity exercise where your body starts breaking down glucose for energy, instead of relying on oxygen.

Working out in this zone has heaps of health benefits, like increasing what's called your lactate threshold. This means your body gets used to working with lactic acid (a chemical that occurs naturally in the body, that can cause muscle soreness and fatigue). As your lactate threshold increases, you'll be able to work out harder and for longer periods of time. Zone 4 is also known for burning fat and using more calories [8].

Zone 5

Final one, the max effort your body can produce. Zone 5 is used for short bursts of intense activity, like in interval training. When in Zone 5, you should be at about 90-100% of your max hr, but never for long periods [8].

What heart rate zone should I be in?

The heart rate training zone you choose to work out in will depend on your fitness goals, health and fitness level, and other factors.

In a low-intensity zone like 1 or 2, you'll burn fat while staying at a pace you can easily maintain. This might be helpful if your goal is weight loss, or increasing your time spent exercising. Higher intensity zones like 4 or 5 will use more energy and burn the most calories overall, but should only make up short bursts of our training time [8].

In simple terms, heart rate zones are just a guide to help you get the most out of your workout. If you're only doing a short session, you might choose to do more intervals in zone 4 or 5 for maximum efficiency. If you've got time to spare, you might do something lighter for a bit longer — like going for a brisk walk [8].

How to start heart rate training

If you're sold and ready to get on the heart rate zone training bandwagon, welcome aboard.

Firstly, you'll probably need a heart rate monitor — like an Apple watch or other smart device. The bonus of these is they can tell you how many calories you're burning if that's something you also want to track.

You'll also need to figure out your maximum heart rate. There are plenty of charts floating around (make sure you use a trusted source), you can use a heart rate zone calculator, or you can ask a trainer or health professional to help you calculate it. These calculations are usually based on your age, but make sure to mention any health conditions or other concerns.

As you begin training, it's best to start low and go slow. You can do this for a few weeks or as long as you need, especially if you're new to exercise [1].

You can build up your intensity over time, and move through zones as you go. A good way to tell if something's too intense is if you can still talk while you're exercising — if the answer is no, you might need to back off a bit. And remember, doing shorter/more intervals at a higher intensity level can help you get used to a new exercise program [1].

If this all sounds a bit much, don't panic. As part of Juniper’s Weight Reset Program, you can access expert coaching and advice from health practitioners to help you figure out what works for you. You can be confident in your training plans knowing they're backed by science, and chat with other community members who are on the same path. The best bit? We'll even help you do the math.

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