Different Athlete, Different Taper

From Running Times

Coaches and runners deal with individuals, while scientists deal with averages. As our elite coaches suggest, individualizing the taper is of the utmost importance. One way to conceptualize this is by thinking in terms of what makes up our muscles. As you may already be aware, human muscles consist of several different types of muscle fibers, which are broadly classified as slow-twitch (ST) or fast-twitch (FT) fibers. In general, the runners who are good at short and fast races have more FT fibers while the ultramarathoners have predominately ST fibers. Given our different mixture in the muscles, it makes sense why so many different peaking methods are recommended and why top coaches give different athletes different workouts. Even if they are training for the same event, our ST-laden ultrarunner is going to respond differently to a peak than our FT-heavy middle-distance runner.

Defining Run Economy

From My Tri Life

The point being: What we do know is that running economy tends to improve when we introduce the Progressive Overload Principle into our training. Why? Because progressive overload is what induces these adaptations.....No matter how you look at it, doing a lot of running at goal race pace, by itself, is not a factor in improving your running economy. It can only become a factor when the stimulus associated with training at goal race pace just so happens to be responsible for creating an overload and therefore eventually inducing an adaptation.