I recently read one of your articles called “Why the Only Running Fitness Test I Really Trust Is a 5K Race”. How would you use this to determine your 80/20 training zones? I understand that you can use the 5K time to figure your pace zones. But what about heart rate or power zone? Is there a reliable way to ascertain either or both of these from your 5K data?
One of the great benefits of the 80/20 system is that you can use a single test to capture HR, Pace and Power thresholds in a single effort (OK, you can do that with other systems too, but we make it easy to implement).
You’ll note in our document Intensity Guidelines for Running that we have a modified protocol for a 20-minute test, which is to take 95% of that 20-minute TT speed to determine threshold pace. Note that you are taking 95% of the speed, not 95% of the pace (see the document for details).
Since many individuals will be within 3 minutes of 20 minutes for a 5K, you can use 95% of your average 5K speed as a threshold. If you take more time than 23 minutes for a 5K, use 97%, and if you take more than 27 minutes, just go 3 more minutes for the full 30-minute time trial! 😉
You can also take 95% of average 5K power to determine threshold, using the same guidelines as above for Pace.
For HR, this is a bit tricky. 97% of the average of the last 10 minutes of the 5K is likely your LTHR.
Again, if you have a HR monitor, GPS, and power meter, you can capture all 3 in a single 5K.