The chart above is one I showed in a blog post a few months ago, where the athlete was progressing in the average pace off all runs in a week. (Click on images to enlarge). The challenge as a coach is to try and keep this upward trend going, for the entire season, and at as steep of a rate of incline as possible, without injuring the athlete. (Injuries will inevitably lead to a decline). So what has happened lately with this athlete? Well, see below. (Again, click on image to enlarge).
Now you can see we've been able to keep the athlete progressing well, on an upward trend, which is something he wasn't able to do at all in the first half of the year. In fact, not only is more of the first half of the year flat, there is a decline in performance come the months of May and June.
When you use data and track how the athlete is progressing, you can continue to look for consistent improvement, and prevent performance plateaus, ahead of time. This is the key reason I have my athletes use technology in their training.