It is a version of Colorado Buffalo fartlek workout that they did in 1998 before their NCAA Cross Country Championship : 1min hard, with a 20 to 30 second jog recovery, but stopping and starting at the exact spot for each rep. Basically, pick a 5k course, run 1 minute at 5k pace, jog 20 seconds to 30 seconds, then start again at the same spot you finished the last rep, don't time the reps, but rather keep an overall time at the end. When you hit 5k your done and you have an overall time. When you finish a rep jog around for 20 to 30 seconds, then go back to the exact same spot you finished the last rep.