The easiest way to approximate your VO2 max is to use a simple equation, based on your max and resting heart rates: VO2 max = 15x (HR max/resting HR)All that being said, you can train to improve your VO2 max, and your overall running performance, without calculating your exact number. The Best Types of Workouts to Boost VO2 MaxWhen it comes to improving your VO2 max, your genes play a huge role. Getting faster by way of VO2 max work is all about efficiency. “If consistent in training to increase VO2 max, people should start to notice a difference in approximately six weeks,” says Gatlin. “In general, VO2 max work should be completed at about 90 to 100 percent of your max heart rate,” says Benson.