Hi,
OldFart here.
At age 77, I now believe I wasted huge chunks of time, energy and youth on base training.
For myself today, I design my structured program, but instead of a base training period I use a lowest possible level of the structure. In training, you adapt to what you do. What you get is what you trained for.
If I were in serious, youthful competition again as an 880/miler, I’d cut the long run nonsense, and stick to speed, speed, speed. (race pace). For sakes, in the early 1960’s we believed a 30 mile plod was greater base training for the mile. That’s more or less where base training myths started. Cooper’s Aerobics did not help either.
Today, where ‘fast waddling’ best describes my running, I have had more success in training for 5-10 k’s by doing nothing more than two-minute reps on a track or road.
In my never humble opinion, decide your distance, decide your race pace, and then train the heck out of it in short time chunks with descending recovery periods.
Hope this is food for thought.
Rod