When we venture down to our local track and prepare for our evening interval workout, we know what the workout is going to be down to how many intervals we are going to run, how fast, and how much recovery we will take. Furthermore, even if we have a coach, we have some control over these variables if the workout starts to go awry. In other words our control of the situation is high and we have a fairly high degree of certainty of how things are going to play our.

On the other hand, if we show up to a race, what we know is how far it will be and our goal pace. We don’t know what our competitors will do, how they will impact our pacing strategy, what we will do if we feel subpar. All that we know is that we have to finish the distance and there can be no adjustments except to our pace and effort. In other words, we have a much lower amount of control and a higher degree of uncertainty.

It may seem obvious, but this degree of uncertainty and lack of control is often what brings the psychological stress that accompanies racing. And while we are really good at preparing for the physical demands of the race and even some of the psychological demands, such as pain, we are really bad at preparing for the uncertainty of a race situation.

In fact, a recent theory on why we speed up and slow down, published in the journal Sports Medicine makes the claim that it is during periods of uncertainty that we are most susceptible to “give in” to the pain. The reason for this is simple. When our bodies face an unknown, it is more likely to err on the side of caution. So if we are running at a steady pace, our brain can have a decent understanding of how the fatigue is going to build up. If all of the sudden every 400m of a 5k we throw in a strong surge to stay with the pack, for a moment, our brain goes through a period of uncertainty.

The good news though is that we can train for these periods of uncertainty to better prepare and mimic race situations. One-way, we have gone about it is to implement uncertainty workouts. During these workouts, the goal is to essentially withhold information to create uncertainty.

How to add uncertainty to a workout:

  1. The simplest method if you are a coach, is instead of telling the athletes the complete workout; tell them what they need to do rep by rep. This makes it where the athlete is unsure of how many they will do, how fast they’ll have to get, and so on. It creates just enough psychological tension because the athlete can’t hold back or pace themselves based on how many repeats they know they have left.

Example: Instead of telling the athlete they have 4×800 in 2:45 and 4×400 in 80, only relay the information on the next repeat to run.


  1. In a group setting, one of my favorite ways to create uncertainty is by the implementation of surges. If you and a few of your training partners are doing a workout together, give each person the opportunity to throw in a surge at any time with the sole instruction that everyone in the group has to cover the surge. What ends up happening is for everyone who is not the surging instigator, you mimic a racing situation where you have to cover moves without knowing how long the person will continue surging for.

Example: If we have a group of 5 people doing a 4 mile tempo run, give each person one surge that they can throw in at any time with the only instructions being that it can be between 30 seconds and 3 minutes in length and that you can only surge once.

  1. For those of you who have to workout alone, it’s harder to trick yourself and bring some uncertainty into the workout. One way we can get around this is by manipulating when you look at your watch for splits. Instead of giving yourself free reign to look at splits every 200m on the track, intentionally delay when you are first allowed to check your splits during each interval while trying to maintain speed.

Example: During a 4xmile workout, run the first repeat at pace while looking at splits. Then during the 2nd repeat do not look at your watch for splits until 800m during the 1st interval. The 3rd repeat don’t look until 1200m, and then the final rep try not to look at your watch at all. The goal is to maintain pace as close as possible, even as you lose the feedback of knowing your splits.


Steve Magness is a performance coach and author of two books, Peak Performance and The Science of Running. His writing has appeared in Wired, Sports Illustrated, Outside, and other publications. He can be found on twitter @stevemagness

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    1. Chandler Maciel on November 14, 2018 at 2:51 pm

      Great Stuff! How often would you implement this and at what points in the season? How would unpredictability in workouts vary from track middle distance to marathon training, etc.?

    2. Erin Vergara on November 14, 2018 at 9:44 pm

      Good strategies, but of course! I think those of us who grew up with just simple watches and unmarked territory were forced to do all these things and it was “normal”…now with all this feedback at our fingertips,it’s almost too much…

    3. Jesse Alt on November 16, 2018 at 4:47 am

      Thanks, this was an interesting post! As someone who does most of my workouts alone, I immediately got to thinking about how it might be possible to improve on the suggestion in 3, and had the following idea: someone doing workouts alone can introduce uncertainty by using dice (or a coin flip), for example by assigning various paces to the numbers on the dice and then rolling before each rep to determine the pace. To mimic the effect in the first two workout proposals, or in races, at least one of the possible paces should probably be faster than you are able to maintain for the total number of rep’s, so you are forced to run that pace without knowing if you will be required to run that pace again (or how many times) before the end of the workout. Other variations could be introduced, such as throwing the dice to determine the rest interval, or the distance and number of rep’s, could also be tried.

    4. CJL on November 19, 2018 at 9:36 am

      I really appreciated this article. As a runner who often trains alone, it is hard sometimes to purposely introduce uncertainty into my workouts. The fartlek style run (#2 above) is one of my favorites as it can be done anytime, anywhere in a group.

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