Here is another great Track Workout that requires no equipment or timer. Just a good pair of sneakers!
You are going to mentally divide the straight 100 yards into 3 equal parts. The first 1/3 you are going to do LEAP FROGS (squat down and then jump as far forward as you can). The next 1/3 you are going to do a grapevine. Then the last 1/3 you are doing good old lunges.
On the curve you are going to run. Push yourself and try to get out of your jogging comfort zone.
Once you get to the straightaway you will repeat the leap frogs, grapevine and lunge sequence. Finish off the lap with a good run. If you need to recover after each lap, stop and take a drink of water. Otherwise go right into the next exercise.
Do this at least for 1 mile, or 4 laps around the track. ~Happy sweating