I'm a huge fan of sprint work on rubberized tracks when it comes to sculpting the bod! In my travels up & down the west coast, I've found these tracks are not readily available for public use...bummer.
Benefits of running on a rubberized track:
~not as hard on joints as running on cement/pavement
~easy to measure distance
~the flat surface is better for ankles...less likely to roll than on dirt, sand or grass training areas
~can gauge speed during drills
~makes for good plyometric surface: bounding, jumping, skipping, etc
Some of my "favorites" on the track:
~sprint corners, jog straight-aways 4 laps
~set up cones (markers) 50-60 meters apart: run down back down back, then take 30sec break and repeat 4-6x
~sprint 200m, jog 100m, walk 100m, repeat 4x
Those are just a few ideas. No matter what my sprint workout is, I always add 2 warm up laps & 2 cool down laps.
Here's the bummer. A lot of tracks are locked up due to vandalism. I also find it odd that so many tracks at California high schools are dirt. Sometimes you can contact the school's Athletic Director or a Track Coach and they can let you know if the track is ever open to the public or where you might find one close by. I've found it's not always and easy task to find an open track though. Good luck!