Are you running junk miles?
The term “junk miles” has become popular in the world of running and race training over the past several years. The FIRST Run Less Run Faster claims that it will bring you a PR in anything from the 5K to the marathon by eliminating any and all junk miles—which, by their definition, are any easy runs.
Proponents of high mileage training, on the other had, overall don’t believe in junk miles. Every run has a purpose, even if that purpose is to add in mileage. Think of the Hansons Marathon Method, in which recovery runs reached up to 8 miles in order to add mileage and cumulative fatigue to your week.
With all of these conflicting arguments and differing definitions, you may be wondering: what are junk miles exactly? How do you know if you’re running them and possibly sabotaging your training or wasting your time and energy? In this post, I wish to provide you with guidelines for determining whether or not you’re running junk miles.
Are you training for a specific race?
If you are in a recovery, base building, or maintenance phase of your annual training cycle, then you don’t have to worry as much about junk miles. You likely aren’t doing hard track workouts or tempo runs and most of your miles will be easy. Just run to run and enjoy it stress-free. Don’t worry about running junk miles as long as your average weekly mileage is reasonable for you.
If you are training for a race, then you should be more aware of whether or not you are adding junk miles to your week, as you do not want to ruin your recovery, accumulate undue fatigue, and toeing the line of overtraining. The following questions will help you determine junk miles within the context of race training.
Does your run have a particular purpose in relation to your training?
Most training plans break down runs into just a few categories: speed work/interval runs, tempo runs, hill repeats, long runs, warm-up and cool down miles, and easy/recovery runs. If you cannot name a specific purpose for a run, then you may be running junk miles. This means that for easy runs, you must run at a truly easy pace, while tempo runs should be at a tempo pace. Otherwise, you are just wasting your time and energy in relation to the achievement of your running goal.
Warm-up and cooldown miles contribute significantly to decreased risk of injury and improved performance during interval workouts and tempo runs; for most runners, 10-30 minutes of easy running of warming up and then 10-30 minutes of easy running for cooling down is all you need to reap the physiological benefits.
Are you running in the appropriate pace zone?
Surprisingly, during race training, junk miles often occur when your pace is moderate. Moderately hard runs, such as tempo runs, and hard interval runs have their places, as they raise your lactate threshold, improve your endurance, and increase your VO2max. Easy runs boost your aerobic abilities, increase your endurance, and help you recover from harder workouts. Those moderate miles, often at the top end of your easy pace but below your lactate threshold pace, do not offer the benefits of tempo runs and speed work but add more fatigue than easy runs. For example, if you are an 8 min/mile marathoner, anything mile between an 8:05/min mile and an 8:50 min/mile could be considered a junk mile, since it will fatigue you too much to have the energy to push yourself in the critical hard workouts. Don’t push the pace on your easy runs and you won’t have as much fatigue in your legs for those workouts that help you run further and faster. (N.B.: Moderate miles can have a place in base building and maintenance phases, since you do not have to worry about too much fatigue in your legs for a hard workout.)
Be aware of exercise bulimia.
A rising phenomenon in runners, particularly female runners, is exercise bulimia, or binge exercising/compulsive exercise. Binge exercisers will run high mileage in order to stay thin and burn off calories from any “bad foods,” and many running and health professionals are beginning to consider exercise bulimia to be a type of eating disorder (this was covered in my RRCA coaching training). It’s a fine line between high mileage for the good reasons of building an aerobic base and training for a long distance race and high mileage for the sole sake of burning calories, so exercise bulimia cannot be generalized and must be diagnosed on an individual basis. One runner’s healthy high mileage can be higher than another runner’s binge exercising mileage, so a definitive marker cannot be set: some runners thrive on 80+ miles per week, while other runners can exhibit compulsive/binge behaviors on significantly lower mileage.
Burning extra calories does not count as a particular purpose related to training. Junk miles occur when you run an excessive amount of miles with very little training purpose: not base building, not a marathon PR, not an ultra marathon. In this case, junk miles should be the least of your concern in the face of overtraining, female athlete triad, stress fractures, and other serious issues. If you are worried that you suffer from exercise bulimia, please contact a sports medicine doctor or other health professional to help you, as this may be indicative of a health problem or mental health issue beyond the scope of your running coach.
(Please note that while I am a certified running coach, I am not your running coach, so I don’t know exactly what works best for you individually.)
But there’s always exceptions:
Sometimes, running is about so much more than exercise and training. If you’ve just come off of a crappy day of work, if you want to run with a child, spouse, or your pet, or you’re getting hit hard by the seasonal blues and need that boost which only running can offer, then these runs most certainly have a purpose.
Are you tired of running junk miles and ready to bring direction and purpose to your running? Consider signing up for one of my running coach programs, such as individualized e-coaching to prevent injury, make your miles matter, and help you achieve your personal best! Read more about my services here and you can contact me at firstname.lastname@example.org to set up a consultation today!
What’s your take on junk miles? How would you define them?
Do you change your paces when you shift from base building/maintenance to training?
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