Track Coach

Training By Time Or Distance

We welcome Jason Karp back to the pages of Track Coach. This is a commonsense approach to equalizing training stress for runners of varying abilities.

By Jason R. Karp, PhD

Beginning in the seventh grade, I became fascinated with time, specifically how fast it moves and how each year seems to go faster than the previous year. Time spent running is also interesting—the second half of runs always seem to go faster than the first half, and some runs seem to fly by while others seem to drag on. This changing perception of time may be partly explained by its relationship to effort, as running philosopher Dr. George Sheehan once noted: “The faster we run, the longer it takes.”

Distance runners and coaches tend to think a lot about mileage. Indeed, it’s the number of miles they run each week that often defines their status as runners. The more miles they run, the more they’re validated. Even other runners will ask them how much mileage they run and make judgments about them based on the answer they give. Even coaches at other schools may ask you how many miles per week your athletes run.

However, the amount of time spent running is more important than the number of miles since it’s the duration of effort (time spent running) that our bodies sense. A faster runner will cover the same amount of distance in less time than a slower runner or, to put it another way, will cover more miles in the same amount of time. For example, a runner who averages 6-minute mile pace for 50 miles per week is running the same amount of time as a runner who averages 7:30 pace for 40 miles per week (300 minutes per week), and therefore is experiencing the same amount of stress. And that’s what matters—the stress. The slower runner may be running fewer miles, but the time spent running—and therefore the stimulus for adaptation—is the same. If a slower runner tries to run as much as a faster runner, the slower runner will experience more stress and therefore puts himself or herself at a greater risk for injury.

Endurance is improved not by running a specific distance, but by running for a specific amount of time. The duration of effort is one of the key factors that arouse the biological signal to elicit adaptations that will ultimately lead to improvements in your athletes’ running performance. Focusing on time rather than on distance is a better method for equating the amount of stress between runners of different abilities. Your athletes’ legs have no comprehension of what a mile is; they only know how hard they’re working and how long they’re working. Effort over time.

Training by time should also be applied to individual workouts. This is the biggest flaw of group/team training, during which everyone on the team runs the same workout. A slower runner should not attempt the same number of reps of the same distance in an interval workout as a faster runner, otherwise he or she will experience more stress because he or she will be spending more time running at the same relative intensity. For example, an 18:00 5K runner who runs 5 x 1,000 meters at 5K race pace will experience more stress than a 15:30 5K runner who does the same workout. The corresponding times of the two workouts would be 3:37 per 1,000 meters (5:48 mile pace) and 3:07 per 1,000 meters (5:00 mile pace), respectively. For this workout, the slower runner would be running 30 seconds (or 16%) longer at the same relative intensity as the faster runner.

To make these two workouts more comparable, and therefore to equate the stress experienced by both runners, the 18:00 5K runner should modify the workout by running 850 meters (which would take 3:04) rather than running 1,000 meters. If 850 meters is too awkward of a distance to determine, you can run either 800 or 900 meters. The point is to make the two workouts more comparable by shortening the distance for the slower runner (or, conversely, by increasing the distance for the faster runner).

There are a couple of other ways to make these two workouts comparable—the 18:00 5K runner can decrease the number of reps or increase the duration of the recovery interval. For example, if both runners run the same distance (1,000 meters) and the 15:30 5K runner does five reps (for a total running time of 15:35 at 5K race pace), the 18:00 5K runner should do four reps (for a total running time of 14:28 at 5K race pace). Alternatively, if the 15:30 5K runner takes three minutes of recovery between reps, giving a work-to-rest ratio of 1-to-1, the 18:00 5K runner should take 3½ minutes of recovery to make the work-to-rest ratio 1-to-1.

While manipulating the number of reps or the recovery interval will make the two workouts more comparable between runners, the best way to equate the stress between these two workouts is the initial way described—shorten the duration of the reps, since the time spent running at a specific intensity represents the greatest aspect of the training stress. If the 18:00 5K runner runs 1,000-meter reps like the 15:30 5K runner but takes more recovery to keep the work-to-rest ratio the same, it’s still a harder workout for the 18:00 runner.

To equate the stress of workouts between runners of different abilities, I have developed a hierarchy of strategies:

  1. Decrease the duration of each rep for slower runners (or increase the duration of each rep for faster runners) to make the duration of each rep the same between runners.
  2. Decrease the number of reps for slower runners (or increase the number of reps for faster runners) to make the total time spent running at a specific intensity the same.
  3. Increase the duration of the recovery interval for slower runners (or decrease the duration of the recovery interval for faster runners) to make the work-to-rest ratio the same.

If your athletes stop training by mileage and start training by time, not only will they do the amount of training that’s right for them, they may even save some valuable time.

A competitive runner since sixth grade, Dr. Jason Karp quickly learned how running molds us into better, more deeply conscious people, just as the miles and interval workouts mold us into faster, more enduring runners. This passion that Jason found as a kid placed him on a yellow brick road that he still follows all these years later as a coach, exercise physiologist, author of 8 books and 400+ articles, speaker, and educator. His most well-known book is The Inner Runner. He is the 2011 IDEA Personal Trainer of the Year and two-time recipient of the President’s Council on Sports, Fitness & Nutrition Community Leadership award. His REVO2LUTION RUNNING™ certification has been obtained by fitness professionals and coaches in 21 countries.