Should training goals be set on #distance or #duration?
Concept of duration versus distance, which should you be using?
Duration is a measure of how long the workout is based on time, not distance. We tend to think in terms of distance because our races are designed that way. What a cyclist typically does when preparing for a race is to determine how much time it will take to do the race. It’s the race time, not the race distance, that is critical to success. So you need to think in terms of duration, not distance in training.
Why?
With rare exceptions, the workouts athletes do are based on duration, not distance. The reason is that the intensity of a workout is specific to its length in time, but not necessarily to its distance. For example, if there are two cyclists in a 40-km race and one finishes in 60 minutes while the other, also working as hard as he can, finishes in 100 minutes, their intensities were not the same. The 60-minute finisher was working at a much higher intensity as a percentage of VO2max. If they were to both cycle as hard as they could for 60 minutes they would likely use almost exactly the same intensity; one would simply cover more ground than the other. But races aren’t designed that way.
The bottom line here is that intensity is inversely related to time. This means that as one increases, the other decreases. As the time of a race or workout gets longer, the intensity at which you are working is reduced. That’s a long way of simply saying that the intensity of your workouts and races is more closely tied to their durations than to their distances. Workouts need to be thought of the same way. Train for duration, not distance.
