Threshold Training: Finding Your VDOT

An aerobic profile involves identifying a vVO2 Max (velocity at VO2 Max) that represents the speed of running a race that lasts about 10 to 12 minutes. This vVO2 Max reflects the runner’s economy and VO2 Max and will be the same for all individuals of equal race ability—although one runner might accomplish his or her vVO2 Max with great economy and a relatively meager VO2 Max and another runner with not-so-great economy and a high VO2 Max. It doesn’t matter how the components vary if they combine to provide the same result. Basically, Jimmy Gilbert and I placed every runner of equal performance ability onto a common economy curve, which meant they would also have the same mathematically generated VO2 Max and a similar lactate-response curve. Equally performing runners are assigned equal aerobic profiles, which means they would also have an identical pseudo VO2 Max but not necessarily the VO2 Max they would show in a laboratory test.

Instead of referring to this pseudo VO2 Max (the one based strictly on performance) as VO2 Max, we use the term "VDOT." VO2 Max is properly stated "V-dot-O2Max." By placing a dot over the V, we’re identifying the rate of oxygen uptake—that is, the volume of oxygen consumed per minute. We shortened V-dot-O2Max to VDOT. This way, each runner has a reference VDOT value: a single number that’s easy to work with when comparing performances. This system is also ideal for setting training intensities because intervals, threshold runs, and even easy long runs and marathon-pace runs are best performed at specific fractions (or percentages) of each runner’s VDOT.

When you know your VDOT value, you can eliminate a great deal of guesswork from training and can avoid overtraining. I’ll go so far as to say that your VDOT takes into account your psychological input into racing, because instead of using lab tests to determine your ability level, we’re using your race performances, which are affected by your motivation and willingness to deal with discomfort. VDOT reflects everything that an individual calls on to perform in a race.

All runners learn to identify the intensity of effort they can tolerate for different periods of time; of course, better runners can cover greater distances than lesser runners in the same amount of time. Using these relationships and equations, Jimmy Gilbert and I developed the VDOT tables that have been used very successfully since the 1970s.

These VDOT tables can relate performances over an unlimited number of distances and can be used to predict performances in races of any distance from a known performance in a race of any other distance. In addition, the formulas associated with the development of the VDOT tables allow runners to identify the pace associated with a desired training intensity (such as •VO2 Max intervals, threshold, or marathon pace).

The table on page 18 presents a condensed version of the VDOT tables found in Oxygen Power (which details VDOT values for more than 40 distances and in smaller increments). A VDOT value can be generated for virtually any performance over any race distance but is most desirable and accurate for races lasting from about three-and-a-half minutes to about three-and-a-half hours.

To use the VDOT table, look up a recent time under any of the distances presented and then read across that row to find the corresponding VDOT. If you have more than one recent race distance to work with, the one with the highest VDOT is the one that describes your current state of fitness.

Make sure that the race from which you’re predicting the VDOT was run on a flat course, with good footing, and under good weather conditions; when using a race run in difficult weather or terrain conditions, time is affected negatively, and the VDOT will be lower than it should be. If, however, you’re determining a VDOT on a cross country course that you’ll also use for regular training sessions, then it’s fair to use the VDOT value from that adverse course to set training intensities for the same type of adversity. You can use a time from a recent, moderate-distance road race to predict an upcoming marathon time, but for the prediction to be accurate, the conditions of the two races must be similar; you can’t expect to accurately predict a hot-day marathon time from a half marathon time run under cool conditions.

Of course, some runners might find that they have different VDOT values depending on the distance of the race. For example, a runner might have a best time of 4:31 for the 1500m (VDOT 61) but a 9:33 for the 3,000m (VDOT 62) and a 15:54 for the 5,000m (VDOT 65). In such cases, select your highest VDOT value for your training intensity.

Exercises to Improve Your Running Speed

*A measure of your current running ability.

Variations in Tempo Pace Based on Run Duration (in Miles)