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Junk Miles

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A few weeks ago, we had a bit of a spirited discussion on this forum about low vs. high mileage. In the course of that thread, a couple of people mentioned "junk miles" in a context that I didn't consider to be junk miles. That got me to wondering. What does the term mean to different people? At the risk of stirring up some spirits again, :) let me throw out a few thoughts. I would be interested in how others view the subject.

Some people consider runs that aren't "hard" training....that is, the short, easy runs we do that are commonly called "maintenance runs"....to be junk miles, and that they should be minimized. Without using the term "junk miles," Galloway recommended such, in his low mileage article in the June issue of RW. I found it interesting that in the same issue, Joe Henderson said in his column that he finds the term "junk miles" applied to these easy runs to be "particularly distasteful." He said he prefers to think of them as "recovery" or "active rest."

In his book, "The Competitive Runner's Handbook," Bob Glover refers to junk miles as those that aren't of "reasonable quality." That's a broad term. But he goes on to define some rough parameters. Running less than 2-3 miles at a time, such as running a mile from home to the gym, for example. And miles run outside of your training heart range of 60-100% of maximum heart rate. The only reference he makes to quantity detracting from "reasonable quality" is mileage crammed in at the end of the week, like Sunday night, just to reach a weekly mileage goal.

In his book, "Daniels' Running Formula," Jack Daniels defines what he calls "quality-junk" as running at an intensity that falls between "easy", "threshold", "interval" and "repetition" paces. In other words, hard runs that provide training benefit (quality), but aren't at an optimum pace to train one of the body's running systems (endurance, lactate threshold, aerobic capacity or running economy) most efficiently (junk.) Marathon Pace (MP) runs fall into this category. Since MP runs are simply for body and mind to become familiar with the pace and don't really "train" anything, Daniels only recommends only three MP runs in an entire 24-week marathon training program. Glover includes two MP runs in the last few weeks of a 16-week program. Any more than that are "quality-junk."

I like both Glover's and Daniels' definitions of junk miles. However, neither really addresses a third consideration.....total effort as measured by run lengths, total mileage and frequency of running/racing. As I said in my posts in the low/high mileage thread, I think that, to optimize training, it's best to run as many miles as practical, consistent with other of life's demands, without inviting injury or compromising the quality of "hard" sessions. As long as a runner does that and stays within the guidelines that Glover and Daniels set out in their "junk" definitions, then I don't think s/he has "junk miles" in his/her training program. If either injury or quality of hard training becomes a problem and there is no other explanation, such as a bio-mechanical problem causing an injury or illness, stress or lack of rest affecting quality, then the runner has some "junk" in the program, i.e., is overtraining, and should reduce mileage....usually from easy, maintenance days, although too much hard stuff can also constitute "quality-junk."

Finally, I don't think junk miles means the same thing to all runners....some can tolerate more mileage or intensity than others, for example. Nor does junk miles mean the same to a given runner under all conditions. For instance, it means something different in a marathon program than in, say, a 5k or a 1500m program. A marathon program should include higher mileage and longer runs than one for a 5k, whereas a 5k program requires a different mix of speedwork than marathon training. Junk miles for one can be quality for the other. In my opinion, a program contains junk miles if the mix of quantity and quality is wrong for the training objective.

What do you think? What does "junk miles" mean to you? How do you avoid them?