Are VO2 max scores on running watches reliable?

VO2 max is a measure of your aerobic fitness. It is the maximum amount of oxygen that your body can use during exercise. A higher VO2 max means that you are able to run faster and for longer periods of time.

Many running watches estimate VO2 max based on your heart rate, pace, and other data. However, it is important to note that these estimates are not always accurate. There are a number of factors that can affect the accuracy of VO2 max estimates, including:

• Fitness level: If you are a beginner runner, your VO2 max estimate will be lower than if you are an experienced runner.
• Your age: VO2 max decreases with age.
• Your gender: Men typically have higher VO2 maxes than women.
• Your genetics: Some people are naturally more fit than others.
• Your environment: Altitude and weather conditions can affect your VO2 max.
• Watch accuracy: Some are better than others, but none are 100% accurate.

It’s worth noting that VO2 max is a relatively static measure. It does not change much from day to day, even if you are training hard. So, if you see your VO2 max score fluctuate wildly from one day to the next, it is probably not a reliable measure.

And VO2 max is not the only measure of fitness. There are other factors that can affect your running performance, such as your running economy and your lactate threshold. So, while VO2 max can be a useful tool for tracking your fitness over time, it should not be the only element that you consider when setting your training goals.

Should you trust the VO2 scores on your watch?

The answer is: it depends. If you are a beginner runner, you may not want to put too much stock in your VO2 max estimate. However, if you are an experienced runner and you are using your watch to track your progress, then the VO2 max estimate can be a handy tool.

But if you are using the watch to compare yourself to other runners or to set training goals, then you should be aware of the limitations of the estimates.

And if you want an accurate VO2 max score, you can always have it tested in a laboratory. However, this can be time consuming and expensive. Prices in the UK, for example, range anywhere between £75 to £250 depending on the location and other services attached to the test itself.