Adequate mileage isn’t the only component needed to perform your best in distance running, but it just might matter most.
The Little Engine That Couldn’t
When I left for college the summer of my freshman year, I loaded all of my belongings into a tiny 1991 Geo Metro and headed out for a little town in North Dakota. It wasn't the prettiest piece of machinery, and beyond basic "A to B" commutes, the car had some serious limitations. With only a 3-cylinder engine to generate power, it was apparent from the start that me and my Metro would be living life in the slow lane. It didn't matter how hard I pressed the pedal to the metal, the tiny engine just couldn’t keep pace with all of the other cars gifted in horsepower.
As coaches, when we've all seen "faster" athletes get beat in races by peers that are "slower" than them based on metrics of max speed or even speed reserve.
Impossible, right?!
Well, no. Frankly put, these more aerobically-developed runners are hitting on all cylinders: they have a bigger engine. The further into the race, the larger their advantage grows.
The good news is, we don't have to settle for the pre-installed engines, we can upgrade.
And this is where mileage comes into play.
In his popular presentation, “Seiler’s Hierarchy of Training Needs”, exercise scientist, Dr. Stephen Seiler touted training volume and frequency of work as the most important aspects of endurance performance. In fact, Seiler’s research found that elite endurance athletes put such a premium on accumulating volume that they perform roughly eight out of ten sessions with the primary goal of building the aerobic engine.
Invisible Adaptations
From the outside looking in, it might seem like success in distance running would be a case of simple mathematics: train at the speed you want to race, rest, rinse and repeat.
And if you come from a speed and power background, running lots of easy miles or threshold workouts a minute slower than you can run a full-out mile might seem ludicrous- or at best, counterproductive.
Why would running slower than the pace of a race help a runner?
Well, there’s magic in the miles.
When a runner increases mileage on a consistent basis, the brain takes that as a cue to begin making a series of adaptations intended to make running easier. Although invisible to the naked eye, these microscopic changes can help young runners chop off big chunks of time. The adaptations from endurance training are complex and I certainly don't understand them, but it seems that there are a couple of key changes that occur inside the body that help give purpose to the miles.
To begin with, increased mileage influences the heart to become stronger and more efficient at pumping blood. Blood contains all sorts of important ingredients, most notably fuel and a vital element for distance runners called oxygen.
From the heart, blood is pushed through a network of arteries and arterioles as it makes its way towards the working muscles. It’s helpful to think of arteries as an expansive interstate system and the arterioles as off-ramps that lead to different muscle groups. At the end of the arterioles are finger-like outlets called capillaries that route blood directly to the muscle fibers.
Through endurance training, the capillary network expands, allowing for more blood to make its way to working muscles. From the capillaries, oxygen is picked up by myoglobin and delivers it to the powerhouse of the cell: the mitochondria.
The Cylinders of the Muscle Fiber: The Mitochondria
Mitochondria are tiny organelles found in muscle fibers that- like the cylinder of a car engine- serve as the epicenter for energy production.
In his book Science of Winning, Dr. Jan Olbrecht explained that an increase in the size and density of mitochondria in muscle fibers is a major determinant of endurance performance.
The quality and quantity of mitochondria determine the horsepower of our aerobic engine. And unlike static physical traits such as height or wingspan, mitochondria can be drastically changed as a response to endurance training.
Progression of Mileage over a Season
If you want to upgrade the 3-cylinder Metro, there's a simple path: run more.
However, to boost mileage safely, you need an intelligent plan not only to take you through a season, but an entire high school career. And you want to do so in a manner that sets your runners up for continued success after they leave you.
It’s sensible to start at a mileage level that’s easy to manage, and within your current state of fitness, before moving onto a higher level. In the popular training manual, Daniels’ Running Formula, Dr. Jack Daniels recommends staying at same mileage for at least three weeks before increasing to a new level.
Daniels then suggests increasing mileage by no more than one mile for each day of the week you run. For example, if you knocked out three weeks of 30 miles on six days of running, Daniels would advise a maximum of 36 miles per week during your next cycle of training.
Another strategy, as advocated by Scott Simmons and Will Freeman in the book Take the Lead, is to use a gradual, coffee-drip approach to increasing mileage throughout the season. The Simmons/Freeman approach, which they coined the “Diamond Model”, gradually builds mileage (along with all other training qualities) from week one, all the way up to the penultimate week of the season.
Other coaches prefer increasing mileage by 10% per week, which has existed in distance running dogma for decades.
Any of these strategies can be effective to create a logical, progressive method for increasing training mileage.
Getting in the Miles...or Minutes?
There's sort of this long-standing debate among distance coaches whether mileage or minutes is better. It really doesn't matter; both methods are effective.
That being said, I use minutes. I've found minutes are easier to progress from year to year and when assigning training to larger groups, it's easier to manage.
Progression of Volume (Minutes or Miles) over a High School Career
One of the best ways to promote long-term performance improvement is to leave some stones unturned each season, and weekly volume is a good place to start.
It’s useful to think of seasonal volume jumps like the rungs of a ladder. When you’re climbing a ladder, it’s not terribly wise to skip steps due to the obvious risk of a fall. Some people will get lucky and keep climbing, but most of us are going to slip, fall and get hurt.
Your inexperienced runners who try to skip steps on the volume ladder often end up injured and end up going back to where they started in the first place!
Patient progression in all aspects of training, especially volume, is vital.
There is an element of art, rather than science, that factors into deciding how each athlete should ascend the mileage ladder.
Oftentimes, taking a step back or simply "staying put" are better choices than continuing the climb.
Here's the progression I use with my team based on years of experience in our high school program, not necessarily their grade.
You'll see volume connections from 1st to 4th year runners and 30 minute weekly increases for every runner, every year.
Experience | Easy Runs | Workout Days | Long Runs |
4th Year | 50' | 65' | 80' |
3rd Year | 45' | 60' | 75' |
2nd Year | 40' | 55' | 70' |
1st Year | 35' | 50' | 65' |
How Fast?
The intensity of easy endurance running, which will consist of ~80% of your training sessions, is a topic of contention for many coaches and runners. The truth is, there is a large range of intensities in which you can perform your weekly mileage and still get the same cardiovascular adaptations.
Dr. Daniels recommends endurance runs be completed in the range of 59-74% of VO2 max. The elites that Dr. Seiler has researched typically ran their easy mileage days somewhere in the middle: ~65% of their VO2 max.
I am terrible at math and the percentages never work out like I feel they should, so I do something super simple.
1600m PR + 3 minutes with a 30 second buffer slower/faster and you have your "Aerobic Run Range".
Example: 5:00 1600m Runner
8:30-8:00= Guideline for Recovery Runs
8:00-7:30= Guidlines for daily Endurance Runs
(Here's a link to a super simple Training Intensity Chart that I use all of the time.)
Finalizing the Engine Upgrade
Turning your little Metros into Mustangs will take work, but fortunately, it’s work that any runner can do and it's easy to program into training.
Just make sure you place as much importance on the "easy days" as you do "workout days" and you'll set your kids up for long-term improvements.
References
Baechle, T & Earle, R, editors. (2008). Essentials of strength and conditioning (3rd ed.): Champaign, IL Human Kinetics.
Daniels, J. (2014). Daniels running formula (3rd ed.). Champaign, IL: Human Kinetics.
Olbrecht, J. (2000). The science of winning: Planning and optimizing swim training: F&G Partners.
Seiler, Stephen, (2016, Nov 23). Seiler’s hierarchy of endurance training needs. Retrieved from https://www.researchgate.net/profile/Stephen_Seiler/publication/310725768_Seiler%27s_Hierarchy_of_Endurance_Training_Needs/links/583590c208ae004f74cc51f5/Seilers-Hierarchy-of-Endurance-Training-Needs.pdf
Simmons, S & Freeman, W. (2006). Take the lead. Simmons and Freeman.
Wilmore, J & Costill D. (2004). Physiology of sport and exercise. Champaign, IL: Human Kinetics.
* Disclaimer: The Daniels' book image is an affiliate link. It's possible I could make a few cents if you purchased the book through the link.
This is a well written post. Lots of great points and easy to follow. Thanks for sharing this. I'm just curious if you have ever used minutes instead of miles for your athletes? I know some coaches use both, some use one over the other. Just curious.