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How to improve your VO₂ max

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  • VO₂ max measures the rate at which your body absorbs and uses oxygen during exercise.

  • A mix of sustained cardio and high-intensity training will improve your VO₂ max.

  • Improving your VO₂ max will help you exercise for longer and at increased intensity.


When we talk about improving your VO₂ max, we’re really talking about improving your cardiovascular fitness - your ability to take in oxygen and transport it around your body, so you can exercise harder for longer. Whatever your sport, improving your VO₂ max will make you fitter and increase your ability to sustain your best performance.

Your VO₂ max - also sometimes referred to as maximal oxygen uptake - is a quick and accurate way to measure your cardiovascular fitness. A few years ago, VO₂ max was the preserve of elite athletes and sportspeople because you needed a face mask and treadmill in a lab to take an accurate reading. Today’s fitness watches and personal heart rate monitors have turned that on its head, offering quick and easy VO₂ max measurements at the press of a button. Fitness watches aren’t quite as accurate as the lab-based method, but they’re good enough to use the results to monitor and improve your VO₂ max performance.

How is VO₂ max measured?

VO₂ max is measured in milliliters of oxygen used in a minute per kilogram of bodyweight (mL/kg/min).

As you breathe oxygen into the body, a metabolic reaction kicks off within your muscles and an organic compound called adenosine triphosphate (ATP) is created. This is the energy source your muscles use throughout your workout. The reason your breathing becomes more laboured and intense during intense exercise is because your muscles need more of this energy as the workout progresses. In basic terms, having a higherVO₂ max means your muscles can convert a higher volume of oxygen into energy more efficiently.

How to improve your VO₂ max

The first step in improving yourVO₂max is to assess your current fitness level. Elite level athletes will already have VO₂ max levels of 65-80 mL/kg/min, far beyond that of an average person which is on average 25-40 mL/kg/min. However, it doesn’t matter where you start, what matters is the improvement in your cardiorespiratory fitness from your personal baseline.

You can find your current VO₂ max level using a fitness watch. Make a note of it and be sure to track it as time passes; any improvement you see is a great motivator to keep going.

There are two main types of training you can do to improve your VO₂ max: continuous training and high-intensity training. Together they can form a heart rate training plan. If you're serious about improving your VO₂ max, it's recommended that youworkout four to six times per week, with a mix of continuous and high-intensity training. For example, four sessions of continuous training, and one or two high-intensity training sessions per week. However, if you’re starting from a low fitness level, don’t rush into high-intensity exercise. Instead, begin with low-intensity continuous training to build up a base level of fitness first.

What is continuous training?

Continuous training is exercise performed at a continuous or sustained effort level, with no breaks. You may also hear it referred to as steady-state cardio. It's typically a form of aerobic fitness, involving exercises such as cycling, swimming, running, rowing or hiking. During this type of training, you should aim to be working within 60-70% of your maximum heart rate.

Continuous training is a cornerstone in the training plans of endurance athletes, helping to improve cardiorespiratory fitness (the heart and lungs) and get the base level fitness needed to complete high volumes of mileage. It's also a good tool for fat loss when paired with a balanced nutrition plan as it has the potential to burn a large amount of calories, even when performed at low intensity.

Continuous training for improved VO₂ max

The duration of time you workout for will vary depending on your fitness level. Beginners should start by continuously running for 30 minutes a few times per week, before gradually increasing the duration week-on-week. For a more experienced runner, a session may be more within the remit of an hour+. Triathlon training is a sure fire way to increase your VO₂ max; an important part of the training plan is what's known as a Brick session, which involved the back-to-back training of more than one discipline. For example, a long bike ride followed by a long run.

What is high-intensity training?

As the name suggests, high-intensity training, or HIIT (high-intensity interval training) requires you to work at a higher level of intensity for shorter periods of time. This type of exercise is particularly good for improving VO₂ max quickly. HIIT workouts are typically performed in bursts of high-intensity exercise. You should aim to be within 85-95% of your max heart rate, during which your body moves from aerobic metabolism to anaerobic metabolism, and lactic acid begins to build up in the muscles. High-intensity training can be applied to aerobic exercises such as cycling, swimming, running and rowing. Many gyms and training plans also offer HIIT workouts which may include circuit-style exercises such as high knees, burpees, and skipping.

High intensity training for improved VO₂ max

There are many different HIIT routines that you can use to improve your VO₂ max. One of the simplest is running up an incline. Once you’ve warmed up, run uphill at a pace you can just manage for 3-5 minutes. Jog or walk back down to the start to give you a rest period of around a minute shorter, then repeat. The reason for the three-minute minimum is that it takes a couple of minutes for you to reach your VO₂ max while exercising hard, so you need to work beyond this to have a positive effect on your oxygen-carrying capacity.

You’ll find that your breathing is ragged and you’ll feel only just recovered when you start the next interval - this is to stop your heart rate dropping too low between intervals. Complete four or five repetitions to start with, then as your fitness improves and you get a feel for the pace you need to run in order to hit the right heart rate zone, aim for up to ten intervals in a session.

Tabata is another form of HIIT training. This ancient Japanese workout has become popular in recent years amongst time-poor fitness fans and can be an effective way of increasing aerobic capacity, but also - depending on the exercises - building strength. A Tabata programme has a strict structure whereby you work at your maximum capacity (85-95% max heart rate) for 20 seconds and rest for 10 seconds, completing eight rounds of a single exercise before moving onto the next.

How to work out you heart rate zones

Calculating your maximum heart rate (MHR) is an easy equation. Simply detract your age from 220. This will give you an average age-predicted maximum heart beats per minute (BPM). For example, if you are 40, your maximum heart rate is: 220 - 40 = 180 BMP. It's important to note however, that this is just an average, and can be out by as much as 10-20 BPM depending on your fitness level, genes or health conditions.

For heart rate training, these are the targets to aim for:

  • Easy (Zone 2): 60-70% of your maximum heart rate

  • Moderate (Zone 3): 70-80% of your maximum heart rate

  • Hard (Zone 4): 80-90% of your maximum heart rate

  • Maximum (Zone 5): 90-100% of your maximum heart rate

To work out a particular zone - for example 70% - multiply your MHR by 0.7. Using the above example, for a 40-year-old this means that 70% of their MHR is 126 BPM.

So during continuous training, a 40-year-old should aim to keep their heart rate between 108-126 BPM, and for high-intensity training, they should aim to spike their heart rate to anywhere between 144-180 BPM.

Final thoughts

Having this type of data available should help you achieve your fitness goals more efficiently, no matter what ability you're starting at. Use your VO₂ max to set goals for yourself, to ensure you are pushing yourself hard enough during more challenging workouts, and to prevent unnecessary over-training during low-intensity exercise.As you increase your body's maximal oxygen uptake, you’ll notice that you are able to go faster and further with less effort; you'll also need to go harder and longer in order to keep your heart rate in the right zone.

Frequently asked questions

What is VO₂ max?

VO₂ max is the highest rate at which your body can take in and use oxygen during exercise. The V stands for volume, while O₂ is the chemical abbreviation for oxygen. VO₂ max - also referred to as maximal oxygen uptake - is measured in milliliters of oxygen used in one minute per kilogram of body weight (mL/kg/min). VO₂ max is an excellent measure of cardiovascular fitness, as oxygen is a vital fuel for your muscles when you’re exercising - the more oxygen you can supply to your body, the more work your muscles are able to sustain. The most accurate way to measure VO₂ max is in a lab with a face mask and treadmill, but a sports watch will give you a good approximation.

Can you improve your VO₂ max?

You can improve your VO₂ max with a workout routine that mixes both high-intensity and low-intensity types of training. Athletes in sports where cardiovascular fitness is key to their success, such as runners, swimmers, and rowers, use their VO₂ max measurements to monitor and guide their training. High-intensity training has the biggest and quickest positive impact on VO₂ max but low-intensity training is also beneficial,

What's the best way to increase VO₂ max?

The best way to increase your VO₂ max is through high-intensity training in intervals, designed to push you to your maximum aerobic capacity. As you train at this level, your body increases its VO₂ max as a consequence. However, you can also increase your VO₂ max through low-intensity, continuous training, for example easy running where you’re working in a low aerobic zone the whole time. This higher volume work is more time consuming but will still raise your VO₂ max. Overall, the best method to increase your VO₂ max is to choose the activities that you most enjoy doing, swapping in changes of intensity when you feel the need for a change.

What does HIIT stand for?

HIIT stands for High Intensity Interval Training, a type of workout that features short bursts of high tempo exercise with short rests in between. It’s designed to keep you working at, or near, your VO₂ max level.

What is HIIT training and why is it good for VO₂ max?

HIIT training involves short bursts of high-intensity training - sets of intense exercise that can last for as little as thirty seconds or a minute, with short rest periods between them. VO₂ max is the highest rate at which your body can take in and use oxygen during exercise. HIIT training at 85-95% of your maximal heart rate is designed to bring you to near your VO₂ max, where you move from aerobic metabolism to anaerobic metabolism. By training at this level, your body will adapt and increase your VO₂ max.

Can supplements help improve VO₂ max?

No supplements have been scientifically proven to help improve your VO₂ max, although there are a number of supplements on the market that claim to boost it. For any exercise or workout, it’s important to ensure that you have the right level of vitamins and minerals in your body. Iron in particular is essential for oxygen transportation.