For years, I have done sprints in the "Tabata" style - a series of 20 second sprints with 10 second rest periods in between. However, based on a few things I read, I've been trying longer rest periods the last couple workouts.
For yesterday's workout, I did 15 second sprints with 3 to 4 minutes rest in between. I tried to go really hard on the sprints, almost at top speed. I noticed today that the workout gave me a much different after-effect. My legs felt more springy, and less banged up than when I do the Tabata workouts.
A lot of this idea is based on the way professional sprinters train. They don't do much distance work, and they take long rests between sprints in practice. Yet sprinters always look so healthy and vital, much more so than middle distance runners or marathoners.
I will stick with these longer rest periods and see how it goes.