Try this (called phosphates)
Mark out a 40m line to sprint and have a stopwatch at hand. Do a good warm up using DROM, DO NOT STATICLY STRETCH!
Sprint the 40m, take a 30 second break, sprint the 40m again. Do this with a 30 second break until you have doen 10 sprints (thats one set). Take a five minute break. Do this 3 times. Try not to do it too soon before a leg day as it will affect your lifts. DO it 2-3 days after legs, depending on your recovery. Let me know how you get on (you should get sick the first time, don't let that put you off though!)
ilds