At this time of year, endurance athletes are encouraged to focus on their base training. But the base of what? Movement and performance are individual and complex so that what is a priority for base training for one person is unlikely to be a priority for another.
An athlete may have several years experience and may need to focus on developing speed (in the context of endurance) to increase their performance. Another may need to build strength so that they can increase their power output for a hilly race. Yet another may need to focus on a run frequency block so that they can eventually do the longer run tempo sessions that they need to get to their marathon goal time.
The base period is not just a time for long, slow movement. It’s a time to explore ways to make you faster.