Using WKO+ to Guide Day-to-Day Variations in Your Run Training

In his latest article, Matt Fitzgerald explains the importance of variation in the intensity of your run training. Using WKO+ to monitor both your Intensity Factor and your Training Stress Score, you can ensure a balanced training program that will help you to optimize your performance as a runner.

You can’t run fast every day, but you need to run fast some days.  Likewise, you can’t do a hard workout every day (whether it’s the pace or the distance of the run that makes it hard) but you need to do hard workouts some days.  In more technical terms, your weekly workout cycle should feature a high degree of intensity and workload modulation.

Intensity modulation refers to changing the pace zone(s) you target from one day to the next.  Each pace zone stimulates fitness benefits in a slightly different way than the others, so it’s important to regularly experience all six of them.  Weekly workout cycles ensure that you do.  Here’s a suggested weekly workout cycle with workout types and the primary pace zone(s) (based on the Pace Zone Index system) targeted in each:

          

Mon	Tue	Wed	Thu	Fri	Sat	Sun
Easy Run  Zone 2 or 3 + Zone 10	Threshold or Interval Run  Zone 6, 8 or 10	Easy Run  Zone 2 or 3	Moderate Run (Progression or Fartlek)  Zone 3 + 6, 8 or 10	Interval or Threshold Run  Zone 6, 8 or 10	Easy Run  Zone 2 or 3	Long Run  Zone 3 or 4

      

Training Peaks WKO+ provides a simple means of tracking your intensity modulation with a variable called Intensity Factor.  Intensity Factor is a measure of the average pace of an entire run relative to your current threshold pace.  If your average pace for an entire workout is equal to your threshold pace, the Intensity Factor will be 1.0.  If your average pace is slower than your threshold pace, the Intensity Factor will be a fraction such as 0.656 or 0.903.  It is rare but possible to record an Intensity Factor greater than 1.0, for example in a short race or time trial.  One reason why such scores are rare, even in very high-intensity workouts, is that warm-ups, cool-downs and active recoveries tend to lower the average pace.  Even so, different types of workouts predictably produce different Intensity Factors.  Seeing a good degree of variation in your Intensity Factors in a week of training indicates that you are modulating your running intensity appropriately.  Here is an example of a well-balanced week of workouts and their associated Intensity Factors:

Mon	Tue	Wed	Thu	Fri	Sat	Sun
5 miles @ Pace Zone 2 +6 hill sprints	1-mile @ Pace Zone 1 6 x 800m @ Pace Zone 8 w/ 400m active recoveries 1-mile cool-down @ Pace Zone 2	4 miles @ Pace Zone 3 + 1 mile @ Pace Zone 4	1 mile @ Pace Zone 3 10K @ Pace Zone 6 0.5 mile @ Pace Zone 2	6 miles @ Pace Zone 3	20 miles @ Pace Zone 3	6 miles @ Pace Zone 3
IF: 0.707	IF: 0.919	0.807	0.967	0.761	0.818	0.770

As in this example, in a typical week you should have two runs with Intensity Factors above 0.9 (fast), two or three runs with Intensity Factors between 0.7 and 0.8 (slow), and the rest between 0.8 and 0.9 (moderate).

Training workload modulation refers to varying your training stress from day to day throughout the week.  Typically, you should have three days with relatively high training stress, two or three days with relatively low training stress, and one or two days with moderate training stress.  Remember, workload and intensity are not the same.  Your high-intensity workouts will typically be among your high training stress workouts, but your long, moderate-intensity runs will often entail the greatest workload.  In Training Peaks WKO+, use training stress score to monitor your workload modulation throughout the week.  Here are the TSS for the week of training presented above:

Mon	Tue	Wed	Thu	Fri	Sat	Sun
5 miles @ Pace Zone 2 +6 hill sprints	1-mile @ Pace Zone 1 6 x 800m @ Pace Zone 8 w/ 400m active recoveries 1-mile cool-down @ Pace Zone 2	4 miles @ Pace Zone 3 + 1 mile @ Pace Zone 4	1 mile @ Pace Zone 3 10K @ Pace Zone 6 0.5 mile @ Pace Zone 2	6 miles @ Pace Zone 3	20 miles @ Pace Zone 3	6 miles @ Pace Zone 3
TSS: 38.7	TSS: 69.4	TSS: 33.1	TSS: 86.6	TSS: 48.9	TSS: 183.0	TSS: 49.2

      

Whether a given TSS score counts as a light, moderate or heavy training stress depends on your individual fitness level, but all runners should distribute their total weekly training stress similarly.  In this example, the total training stress for the week is 508.9.  Together, the two high-intensity workout days account for a little less than a third the total TSS for the week.  The long run accounts for another third, and the remaining four easy to moderate days account for the final third.  This is a good balance for a long-distance runner (half-marathon and marathon).  If your race distance is 10K or less, aim for a distribution that’s closer to 50 percent of total weekly TSS on your two high-intensity days, 25 percent in your long run and 25 percent in your easy runs.

About Matt Fitzgerald
Matt Fitzgerald is a journalist, author, coach and runner specializing in the topics of health, fitness, nutrition, and endurance sports training (read more about Matt on his blog). Matt uses TrainingPeaks to train, coach and deliver pre-built training plans for runners including training plans built specifically to be used with a Garmin Forerunner.