Understanding Training Load

ack when I started running, I learned that miles were king. They were essentially the end-all be-all for tracking training even when we were guessing sans GPS watches. Measuring vertical gain? Forget about it. Now it’s a different world. Heart rate monitors and GPS technology are ubiquitous, and estimates of running power and various biomechanical measures such as stride length or contact time will soon be the same. There is no shortage of variables to use to quantify training stress and performance. Platforms like Strava, Training Peaks and Suunto use some of that data to create their own metrics to quantify our daily and weekly effort. However, the utility or basis of these “black box” metrics of our training stress are not always well understood, and the wider applicability from cyclists to road runners