Monthly Archives: August 2014

Running the 80% / 20% Rule

This recent article from Matt Fitzgerald basically says that elite runners and less-elite runners can follow the 80/ 20 rule. 80% of distance at easy or below threshold running and 20% of hard or above threshold running. Research from many elite runners bears out an 80 / 20 ratio or very close to it. Fitzgerald’s recommendation: whatever your total mileage, follow the 80 / 20 rule.


To back up for a minute the 80% / 20% rule has been around in many applications. It is known as the Pareto Principle, named for an Italian economist from the early 1900s. He noticed that 80% of the land in Italy was owned by 20% of the population. He later found that ratio in several other areas. Today we see it applied in several examples:

Work: 80% of the work in an organization is done by 20% of the employees.

Charity: 80% of donations come from 20% of donors.

Sales: 20% of customers buy 80% of your merchandise.

Projects: 80% of value is achieved with the first 20% of effort


I agree and would take it one step further. (I’don’t have a scientific study to back this up but let me know what you think)

I'd add some miles! Adding miles is always a good thing, right?
I’d add some miles! Adding miles is always a good thing, right?

The Coach Dan Clark Principle: 80% of your running potential can be achieved with 20% of your miles.


WAIT! Dan Clark, the high mileage disciple is saying WHAT!? Stay with me here. 20% of your miles is the “hard” mileage: Intervals, tempo runs and those last few miles of your long run that really hurt. So if you only did the hard miles, then you could reach 80% of your potential. That’s how “Run Less Run Faster” works. That’s how the 3 day a week training plans work. They get you most of the benefit with only 20% of the work. So if you are interested in achieving 80% of your potential, those plans work fine. This is also the realm of the High Intensity Interval Training (HIIT), CrossFit and many other fitness fads that are prevalent today. They say “Do cardio the right way! Do Intervals!” They are 20% right. It is not an either / or scenario. It isn’t bad cardio vs good cardio. You need both in correct doses.


For distance runners, the correct dose is about 80% base miles (zone 2, training effort, conversational pace or however you qualify it) and 20% hard (Track work, tempo runs etc). So log your miles, run your track workouts, get in a tempo run and strive to achieve 100% of your potential.