Lets say a 800m runner does this type of intervall sessions during the base training:
6x1000m 1min 30 sec rest
10x300m 1min 30 sec rest
8x600m 2 min rest
8x150m 3 min rest
Over the the course of base training, what would be a smart way to progress?
Try to Increase speed?
Shorten rest?
Increase number of intervalls?
Increase the length of each intervall?