Motivated to run faster, many athletes focus on ways to improve VO2 Max levels. VO2 Max is the maximum amount of oxygen that our bodies can uptake and is measured as the quantity of oxygen per body weight over a set period of time. VO2 Max is affected by our heart’s volume per stroke, the total volume of blood in our system, and the hemoglobin’s ability to carry the oxygen.
So why would we care about improving what seems to be an arbitrary number? Our VO2 Max is a tell-tale sign of our level of conditioning. And while there are genetic factors that are not in our control, there are plenty of things we can do to improve VO2 Max and our level of performance along with it. By increasing the duration and intensity of our training, we will strengthen our heart, promote the growth of more capillaries in our muscles, reduce body fat levels, and increase our ability to perform better.
Levels of VO2 Max in a sedentary person can range from 20 ml/kg/min. to 50 ml/kg/min. Many elite endurance athletes have VO2 Max levels between 70 ml/kg/min and 90 ml/kg/min. Studies have shown that someone who is just starting to run can improve VO2 Max levels from 20-25% by building up their running routine to 25 miles per week. Runners that increase their weekly mileage from 25 miles per week to 50 miles per week can see an increase in VO2 Max of up to 10%...and the increase percentages get stingier from there for the advanced runners that increase their mileage above 50 miles per week. And while increases in mileage will continue to enhance our performance, it’s the speed workouts that will have the most lasting impact on VO2 Max levels.
Testing actual VO2 Max levels is done by taking blood and air volume samples at various points of exertion and exhaustion from an athlete during exercise. This can be expensive, tedious and unnecessary unless you’re a scientist or student with inexpensive access to a lab. It’s not critical that we know our actual VO2 Max “Number”, but figuring out our interval pace that will improve VO2 Max and performance level can be a definite benefit. So for the rest of us, here are some ways to determine our VO2 Max level & pace:
When trying to conduct workouts that improve VO2 Max, try to sustain that pace for approximately 3-4 minutes, which can equate to intervals of 800-1000 meters. Using the example above (if your 5k PR = 21:42), you’ll want to plan your VO2 Max workout to run 800-meter intervals at a 3:15-3:20 pace. Initially try running 3-4 intervals that are 800-1000 meters long at your VO2 Max pace to start out with. As you progress, work up to 5-8 intervals. Take a 3-4 minute recovery walk/jog between intervals and make sure that the intervals, themselves, are run with some intensity…but not all out (use above rules-of-thumb for pace guidance). Because of the intensity and your body’s recovery & rebuild time needed, be sure that you limit VO2 Max workouts to once per week
If you are new to speed work or are just starting out in a running program, improving VO2 Max should take a back-seat to just building up of weekly mileage. In other words, focus your efforts on running comfortably for 30-45 minutes 4-5 times per week for several weeks before you start any serious speed work.
Because VO2 Max is measured as the actual maximum oxygen uptake per unit of body weight, we could also significantly improve VO2 Max by decreasing our body fat percentage. Notice that I didn’t say “decrease our weight”, because the loss of water and muscle weight will not benefit our performance…it will hurt it. So the silver lining of slimming down, could be some faster times! Keep that in mind when you reach for the cookie jar ;-).
Add mileage and intensity into your workouts once a week to improve VO2 Max. By increasing your aerobic capacity, you’ll see an improvement in your conditioning and your race times. See you at the track!