Having sprinter or power athletes go on 15 to 20 minute distance runs is literally a death march. Slow running for sprinters doesn't help running mechanics and it causes lots of stress on the joints. I would never want the sprinters I coach using 5,000 meters strides when sprinting and it does not do anything for technique. There are many problems that can happen if a sprinter runs long slow distance runs. One, it converts intermediate TypeIIA muscle fiber into slow twitch Type I fiber. And two, it is not a good quality method in developing aerobic capacity, power, and VO2 max.
For sprinters, I would use interval training as a means od developing and addressing aerobic requirements. A good example of interval training is 10x200m at 70-75% with a 1:30-2 minute recovery.
Interval training is good for preservation of running technique and short recovery times produce the same aerobic benefits as distance runs. When designing a good off season fall program for sprinters use interval training methods to develop good aerobic capacity and leave the distance running for the endurance athletes.
