How to Use Predictor Workouts
A predictor workout is meant to help a runner estimate the outcome of their race. For example, my “go-to” predictor workout for a 1 mile race is 2x 800m (or half-mile) with full recovery, so about 8-10minutes.
I run the first 800m at my goal race pace, then take a looooong rest, and run a second 800m faster — as fast as possible.
Predictor workouts will of course be different for every race distance, and even for runners targeting the same race distance, there can be several options for a predictor workout.
For example, marathoners will often use a hard long run in the middle of a high mileage training block as a predictor workout, where others will use 10-12x 800m repeats.
Just about every free training plan available includes predictor workouts to help the user figure out if they are “on track” for their goal. Here are my tips on how to best use predictor workouts to help prepare for a race.
1) The Workout Should Be Open-Ended
Most predictor workouts in existing training plans are designed for a specific goal pace. So if you nail the workout, you are supposedly ready to run that goal pace for the race. But it’s problematic to cater your training for a goal pace. It is much better to determine your goal pace based on your training, and here’s why:
Say you have a predictor workout that is honestly slightly too hard for your fitness level. If you start out on pace, you’ll blow up before the workout is over. This will be a hit to your confidence and on top of that, you won’t even have the data of a full predictor workout to help you estimate your race.
So ideally, choose a predictor workout that involves some sort of progression based on effort. (My 2x 800m is like this because the second 800m does not have a goal pace. It’s simply, go faster than the first 800m, as fast as possible).
Don’t hesitate to give your full effort on this kind of workout. If you really want to do an interval workout with goal paces, make sure to at least review your recent training and adjust the goal times if you realistically don’t have evidence that you can successfully complete it as outlined.
2) Run on Tired Legs
Predictor workouts should be run in the middle of a full training block because they are generally designed to be run on tired legs. We would we lose valuable training time by tapering just for a workout. So when you use the results of your workout to estimate your race result, that estimate takes into account the fact that on race day you will be rested and fresh.
So if you feel tired on the day of a predictor workout, that is totally fine. In fact, if you feel like you need to be at your very best to nail a predictor workout, it’s probably too hard a workout and the pace goals need to be adjusted.
3) Use the Same Workouts Repeatedly
Predictor workouts are most valuable when you’ve used them in the past. If you’re trying a predictor workout for the first time, the purpose should be for gathering data rather than for predicting your upcoming race outcome. This is because runners have a variety of strengths and weaknesses.
For example, if two marathoners are training for a race, one may be more “speed oriented” than the other, ie. better at mile repeats, fartlek runs, etc. The other may live for long runs and mileage. If both of these runners attempt repeat 800’s as their predictor workout, it is clear that the speedy runner will have a better result because the workout suits their strengths.
It really doesn’t matter if the predictor workout suits your strengths, but if it does, you may have an inflated estimate of your race. Once you have the results of the predictor workout AND the race result to go with it, you’ll have a much better idea how to use the predictor workout to estimate your future races. The more times you execute the workout, the more effectively you can use the results to estimate your race.
4) Don’t Over-Do It
A predictor workout should only be used once a season, or once a build. If the workout doesn’t go well, don’t try to repeat the workout before your race. The predictor workout is usually a really hard or “all-out” effort which is harder to recover from than a normal workout, and should be planned strategically in advance of the race — close enough so that your fitness is about where it will be for the race, but with enough time to recover. By attempting to repeat the predictor workout prior to your race, you risk compromising your taper and race result.
Nicole Sifuentes is a full-time Running Coach for adults of all ages and abilities. She is a former professional runner and 2-time Olympian, and Certified Strength and Conditioning Specialist. Read more about her services, and schedule your free coaching consultation.