Your VO2 Max
by Amby Burfoot - from
Runner's World Online
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Understanding how your body uses oxygen
during exercise is the key to faster times
Definition: VO2max is maximal oxygen uptake.
The maximum capacity for oxygen consumption by the body during maximum
exertion. Also known as aerobic power or maximal oxygen intake/consumption.
VO2max is a commonly used determinant of aerobic (cardiovascular) fitness.
Aerobic fitness relates to how well your cardiovascular system works to
transport and utilize oxygen in your body. The better your aerobic fitness the
higher your VO2max. The most accurate way to measure your VO2max is to perform
a maximal exercise stress test in a laboratory. VO2max is usually expressed in
ml*kg-1*min-1, sometimes in ml*min-1.
All aerobic endurance activities,
like running, bicycling, swimming, and cross-country skiing, are essentially
contests to see how much oxygen your body can deliver to your exercising
muscles. Increase the amount of oxygen, and you can run, bike, swim, or ski
In running, of course, those muscles are in your legs. As you
train, two things happen to improve your muscles' ability to use oxygen. First,
your heart gets stronger and delivers more oxygen; and second, your leg muscles
get better at using the oxygen.
In their laboratory research,
scientists frequently measure this delivery and use of oxygen, calling it
maximum oxygen uptake or VO2 max. They consider maximum oxygen uptake to be the
most basic measure of aerobic fitness, and they've shown that it increases as
you train more and harder. I generally reverse the letter order, since max VO2
has a friendlier sound than VO2 max.
As your aerobic capacity
increases, you can run farther and faster. All training improves your aerobic
capacity, even slow, relaxed jogging. But some workouts improve it more than
The best and most efficient way to increase your aerobic
capacity is to run slightly faster (10 to 30 seconds per mile) than your 5-K
race pace. Faster runners should be closer to the 10-second figure, and slower
runners closer to the 30-second figure. For example, if you can race a 5-K at
7:40 per mile, you should run your max VO2 workouts at 7:20 to 7:30 pace. This
isn't a pace that you can maintain very long in training. You can run for
distance (800 meters) or time (3 to 5 minutes).
After each repeat,
jog for four to five minutes, and then do another. The workout is finished when
you've completed three to four repeats (for beginning and intermediate runners)
or six to eight repeats (for advanced runners).
Many runners do max
VO2 workouts on the track as part of their interval training routines because
they like to measure the lengths and times of the repeats exactly. That's fine,
but it isn't necessary. You can also do max VO2 workouts on a good trail, a
grassy field, or any other smooth surface that allows you to run at a fast clip
without fear of ankle turns. Use your watch to time the four-minute repeats,
and run at a strong and fast (but not all-out) effort.
Don't do these
aerobic-capacity workouts more than once a week, and skip them on weeks when
you have races. These workouts cover less distance than tempo workouts, but
they're more taxing because the pace is considerably harder. If you were to do
several max VO2 workouts a week or include one in your training program during
the week of a race, you might soon find your race performances deteriorating
because you'd be too fatigued to race at full strength.
5 Principles of Max VO2
Maximum oxygen uptake, or max VO2, is
a scientific measurement of the amount of oxygen your body can deliver from
your heart and use in your major exercising muscles. As you get fitter, your
maximum oxygen uptake increases.
- All running increases your aerobic
capacity, but the most efficient workouts for increasing it are those in which
you run slightly faster than your 5-K race pace. For example, run 4 x 800
meters at 10 to 30 seconds per mile faster than your 5-K race pace. Jog for
four to five minutes between repeats.
- You can also run aerobic-capacity
workouts off the track by running hard and fast (but not all-out) for three to
five minutes at a time. Jog for four to five minutes between repeats.
- Do aerobic-capacity training only once a
week, and skip it on a week when you have a race. Otherwise, you risk
overtraining and increasing your fatigue rather than your performance.
- After six weeks of max VO2 training, take
a break from it for four weeks. Concentrate instead on longer, more relaxed