Buzz
Many fitness trackers these days provide your VO2max score, sometimes labeled as your 'cardio fitness' level or compared to the fitness of others. While tracking this number can be entertaining as it fluctuates with your training progress, it doesn't necessarily offer a complete representation of your overall fitness.
There are countless ways to measure fitness, and no single metric can encapsulate all aspects of it. For instance, one person might be capable of deadlifting 800 pounds but struggle with even a few push-ups. Another individual may excel in short sprints but fall behind in long-distance running. Our muscles, lungs, and other body systems collaborate to create athletic performance, making it impossible for any one number to define overall fitness.
So, what exactly is VO2max?
We have a full explanation here, but in short: the higher your VO2max, the more efficiently your body can perform intense physical activity over longer periods. Someone with a higher VO2max can outrun someone with a lower VO2max, assuming all other factors are equal, because they are able to maintain a faster pace throughout their workout.
The term VO2max refers to the traditional method of testing it—usually in a lab setting, where you're connected to a breathing mask. It measures the maximum volume (max) of oxygen (O2) that your body can consume and utilize per minute. (This is recorded in milliliters of oxygen used per minute for each kilogram of body weight.)
A higher score is better. Someone who doesn't engage in much cardio might have a VO2max in the 20s, while an endurance athlete could reach the 40s or beyond. Your age and gender also impact your score, with women typically having a lower result than men, and older individuals scoring lower than younger ones. (This is why fitness trackers often compare your score to others of your age and gender.)
Is it reliable?
Fitness trackers estimate your VO2max based on the data they can gather. So, no, they aren't as precise as having a VO2max test in a lab. However, the information they provide can still be helpful.
A fitness tracker often estimates your cardio health by monitoring both your heart rate and the pace during activities like running. If your heart rate spikes significantly when you're running a 10-minute mile, it’s likely that your VO2max is lower compared to someone whose heart rate barely rises over resting levels at the same pace.
The calculation also considers other elements, such as your weight, since VO2max is adjusted based on body weight. To ensure the app provides accurate readings, regularly update your profile and make sure you're actually engaging in running workouts. If you never do these exercises, the data won't be meaningful or reliable.
To figure out which workouts are relevant, consult your device's specifications. Most trackers require running or brisk walking sessions lasting at least 10 minutes, with your heart rate reaching a decent cardio zone. You'll get the best results if you avoid inclines and stick to flat terrain. Fitbit and Apple's guides outline their VO2max calculation methods, while Garmin offers five distinct ways to determine your score.
What insights can you gain from your VO2max score?
If you're receiving a reliable VO2max estimate, the key takeaway is to observe how your score improves as your cardiovascular fitness enhances. While it's tempting to stress over minor fluctuations, especially when you take breaks, try not to place too much focus on the number itself.
Why are you working out in the first place? If you're preparing for a race, your training pace and time trials should reflect whether you're improving. If your cardio routine is simply for overall health, following a sensible schedule ensures you're putting in the effort, regardless of the numbers. So, take a moment to decide if this figure truly matters to you.
To boost your VO2max, you can engage in cardio more frequently, consistently, and occasionally at quicker paces. Both long, slow sessions and short, intense workouts contribute to cardiovascular improvement, and a well-rounded exercise routine should incorporate both.
What doesn't VO2max reveal?
Your VO2max estimate doesn't provide insight into your muscle strength, agility, or skill in your sport. It doesn’t assess the efficiency of your stride, nor does it measure your ability to maintain the mindset and planning required for long-distance races. It also doesn't predict your actual VO2max if you were to undergo a lab test.
In the sports world, there are numerous stories of individuals who were told that certain metrics—sometimes their VO2max, sometimes another statistic—would limit their success, yet they defied the odds. There are also those who achieved great numbers but never lived up to them. Runner’s World points out that an 18-year-old cyclist, with the highest recorded VO2max, ended up retiring from the sport after a brief, unremarkable professional career. The takeaway: VO2max isn’t everything.
