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Part II: Where Is Your Sweet Spot Mileage?

Let your body's response to training determine how much you train.

Let your body’s response to training determine how much you train.

In my last article I proposed that every runner has a unique personal “sweet spot” weekly mileage range that will produce the greatest possible performance improvement. I also suggested that this sweet spot mileage is often quite far removed from the maximal weekly mileage that a runner can tolerate. In this piece, I’ll offer some practical tips on how to go about determining your own sweet spot mileage.

The logic that informs the process of identifying your sweet spot is based on two truisms of athletic training, frequently voiced by my buddy and Endurance Corner coaching partner, Gordo Byrn (a 2:46 marathoner and Ultraman champion):

– Getting tired is the point
– Get tired the right way

Getting tired is the point … to a point. The first principle of training is that it takes an unfamiliar load that initially makes the athlete tired in order to elicit an adaptive response.

After a tough training block, the athlete’s performance is initially suppressed due to fatigue, but over time, the body “super-compensates” and the athlete becomes fitter and is able to handle more load than he could in the previous block. This process has been likened to compressing a spring and then letting it rebound beyond its initial height. The runner then catches the spring, hits a harder block of training in that elevated window, and the process repeats. This is the essence of effective training.

If we compress the spring too far with a few too many miles, however, we risk breaking the spring and missing out on the performance rebound. When this happens, overtraining occurs.

The focus, therefore, for the intelligent runner is on compressing his springs just the right amount so that they rebound in an appropriate amount of time. This “response focus” is different from the “load focus” of most runners, which is inappropriate because it leads to the problem of runners putting a 50-mile weight on a 30-mile spring.

So what is “just the right amount?” Overtraining studies frequently show lasting performance decrements of 10 percent or more in long-term, overtrained runners. In other words, compressing your spring to the point that your training performance decreases by more than 10 percent is flirting with fire. Through experience in coaching athletes with a wide variety of recovery abilities, I have settled upon the 5/25 rule and the “best test” rule as good markers of when “enough is enough.”

When the athlete slows by more than about five percent for a given training session, or if the volume of the session is cut by about 25 percent, I consider the athlete “tired enough.”

I have found that these numbers typically allow an athlete to recover performance (and then some) with one, 7- to 10-day unload cycle per month.

The second rule works like this: If an athlete is unable to pull out a season best test performance once a month, then the mileage in the preceding loading block was likely too much and the athlete has damaged his spring (or the athlete has reached the performance limits of that season, in which case resting and/or racing are in order).

In summary, it’s this coach’s opinion that many runners could benefit from shifting focus from hitting X amount of miles per week to hitting as many miles as it takes to get an appropriate response. In this way, athletes will be able to truly hone in on the slowly moving target of their personal sweet spot mileage.


About The Author:

Alan Couzens, MS (Sports Science), CSCS, PES, is an exercise physiologist and coach who helps athletes at He has a passion for performance and has been coaching endurance athletes since 1993.