Maximum Oxygen Intake (VO2max)

In reading the running literature, one see discussions of VO2max. VO2max is a measurement of your maximum oxygen intake. All muscular movement, as well as the functioning of internal organs need oxygen. When we start running, our breathing rate increases to give our body additional oxygen to support the increased activity. If a runner can increase his or her VO2max, the person can get additional oxygen with less increase in breathing-rate. If you're a recreational runner who isn't interested in competition, you probably won't be concerned how fast you run and you probably won't do speed workouts. You can thus ignore VO2max. However, if you're a competitive runner who wants to increase your speed, you will need to train to increase your oxygen capacity or VO2max, because increased speed needs additional oxygen.

VO2max Training

You increase your VO2max by running fast followed by jogging for recovery. This is a fast pace but not "all out". Runners typically train for VO2max by running faster than their 5K pace for 3 to 5 minutes (the amount faster depends on the condition and age of the runner), with 4 or 5 minutes of jogging afterward for recovery. An example of a VO2max pace might be running intervals at 10-30 seconds per mile faster than the 5K pace. VO2max training is very stressful on your body, and beginning runners should not do it. VO2max training will cause heart rates to be 85% to 95% of maximum.

Estimating VO2max

Instead of putting great stress on your body to measure your maximum oxygen intake, you can estimate your VO2max. One equation that gives a reasonable estimation of maximum oxygen intake is the following

VO2max = 15(HRmax/HRrest)

That is, divide your maximum heart rate by your resting heart rate and multiply that quotient by 15. As one trains as a runner, his or her heart rate decreases because their body becomes more efficient in using the oxygen delivered to it, thus reducing the rate at which the heart pumps blood. The fast pace described above for measuring VO2max is a good way, probably the quickest way, to reduce your resting heart rate.

Look at the ratio of the two heart rates. You can increase your VO2max by increasing your maximum heart rate or by decreasing your resting heart rate. There isn't much you can do about increasing your maximum heart rate, because that is a product of the biological properties of your body. But, there is a lot you can do to reduce your resting heart rate. The fast running that is described above will, over time, decrease your resting heart rate. For example, a typical heart rate for non-athletes is 70, although that value varies with the individual. During my mid 40s when I ran marathons, my wakeup (resting) heart rate was 44, and it dropped to 40 as I trained for marathons. During marathon training, my resting heart rate was significantly below the typical heart rate for non-athletes, indicating that my body received more oxygen per heart beat than bodies of typical non-athletes. Although I'm no longer training for marathons and am older, my wakeup heart rate is 53 and is still below the typical values of non-athletes. And, my VO2max (estimated 45) is significantly higher than that of non-athletes my age (estimated 28 - 35). During my marathon training, my estimated VO2max was 67.

Performance Calculator

B. I. Rapoport, a MD/Ph.D at MIT and Harvard, has developed a calculator to estimate VO2max and to give the number of calories needed to complete a marathon within a specified time. The calculator is an easy way to estimate ones VO2max, as well as to give the number of calories one will have to take before or during a marathon to meet ones goal of a completion-time for the marathon.

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