Junk Miles
The term “junk miles” refers to slow running or jogging that isn’t worth doing. It is a misconception that if our pace or effort isn’t quality, there’s no point in running more. Or, if we don’t have a “purpose” for the milage it’s pointless to run more.
Training that is often considered “junk mileage:”
Extra long warmup or cooldown runs
Adding on that extra 0.X to get to a nice round number on the daily mileage
Short and easy double runs (second run of the day)
Easy running should NOT be considered “junk” unless:
It is contributing to an injury or overtraining.
It interferes with your recovery for a key workout or race.
Big picture, if you don’t have time or energy for a ton of training, easy miles should be the first thing to cut back on. Skip the cooldown and the easy double run. Cut the easy runs short. But please know that these so called “junk miles” are valuable and have a purpose! Here’s why:
1) More energy when it starts to get tough!
Our bodies use fat, protein and carbs for energy, and carbs provide the quickest source of energy. Easy running makes the body better at using fat as energy, which delays the use of carbs for energy. That’s what we want!
We need those carbs for high effort exercise, so we want avoid using up that source of energy as long as possible. We want quick energy available for the end of our races and workouts when we’re tired and effort is high.
2) Quicker Lactate Clearance
(don’t tune out! Read the illustration below if this runner jargon is a turn off)
Easy running makes our body better at clearing lactate. Lactate is created (as a byproduct) when our body uses carbs as energy for those high efforts. We want to be good at clearing lactate because when lactate accumulates, it slows down our ability to keep converting carbs into energy.
Here’s an illustration:
You are washing dishes by hand and placing them in the drying rack. Your friend is taking the clean items off the drying rack and putting them away. But you’re adding dishes to the rack faster than your friend is clearing them away. You are forced to slow down your dish washing pace.
The dishes in the dry rack are the lactate. The lactate is being cleared so slowly that you are forced to slow down.
3) More Time on Feet
A huge part of a successful endurance performance is the physical conditioning to be out on the roads or trails for 3 or 4 or 5 + hours. This is an important consideration for recreational runners who don’t train daily for hours on end like elites do.
Adding More Volume
Adding more easy running or jogging is not very risky as long as it’s done gradually and the effort is ACTUALLY easy. Where many runners go wrong is they add more volume but it’s not truly easy.
Related: Is Your Easy Run Truly Easy?
If you can include more easy running without compromising your recovery, your key workouts, or your health, it is NOT junk.
**I wrote about these concepts in the most basic language possible with the goal of making them easy to understand. If you want to read more in depth and/or have a background in biology, you will probably appreciate this article.
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.