Diastra A series in 6 parts
VO₂max, explained
VO₂max is the most oxygen your body can use in a minute of hard work. It is the number that sums up endurance fitness best, and Apple Watch estimates it as Cardio Fitness.
This series covers what the number means at each age, how training raises it, how far the watch's estimate can be off, and the two workouts runners use to push it and test it.
VO₂maxVO₂max by age for men and womenVO₂max by age and sex from 16,278 lab treadmill tests in the FRIEND registry, how a watch estimates it, and how fast it falls with age.VO₂maxHow to improve your VO₂maxWhat raises VO₂max, how hard and how long the intervals should be, how fast it changes, and what to do when your number will not move.VO₂maxHow accurate is the Apple Watch VO₂max estimate?Three lab studies found Apple Watch read VO₂max 4.5 to 6.3 mL/kg/min below a lab test. What moves the estimate, and how to read it as a trend.VO₂maxWhat is Cardio Fitness on Apple Watch?Where to find Cardio Fitness on iPhone, how Apple Watch estimates it, what Apple's four levels mean, and why the number may not show yet.VO₂maxThe Norwegian 4x4 workout, step by stepFour 4-minute intervals at 90 to 95% of max heart rate with 3 easy minutes between. How the Norwegian studies ran it and how to run it yourself.VO₂maxThe Cooper test, a 12-minute run for VO₂maxHow to run the Cooper 12-minute test, turn your distance into VO₂max, see how close it gets to a lab test, and read what the finish says about your max.