What Is VO2max?
The more you work out, the fitter you'll get. Your VO2max, sometimes described on wearables as a "cardio fitness" score, is a number that tends to be higher among people who are more cardiovascularly fit. But it's not the only measure of fitness, and you should know what it really means. What VO2max really is (as measured in a lab) Smartwatches and fitness trackers don't actually measure VO2max; they just estimate it. To actually find your VO2max, you'd need to go to an exercise lab and do a test on a treadmill or cycle while hooked up to equipment that measures your heart rate and the air you're exhaling. I did exactly this kind of test to compare my real VO2max to the numbers reported by nine different devices. You can read about my experience, and why it matters, here . VO2max, properly rendered VO 2 max , is the maximal volume (V) of oxygen (O 2 ) your body can use per minute during exercise, scaled to your body size because larger people will natu...