Sprints on a Treadmill

I amazed myself yesterday as I managed to do 10x30seconds runs (8kph) with 30sec jogging (7kph) intervals in between  for a total of 10 minutes.  I then walked for 5 minutes and did another jog for 5 minutes.  So a total of 15 mins running/jogging on the wretched machine.  So just maybe I can do a sprint session once a week to boost up my speed.   Will also try to up the running speed a little each week.  Watch this space.