Dizzy but felt great!

Ran 12 km's around the track with T tonight. Apart from the boredom of running round and round and round and ......... I felt great. Started off very cruisy and progressively picked up the pace each km. 4:58 1st km, then 4:42 then slowly down to 3:53 for the final km. Felt very easy the whole way and at conversational pace. Time - 53:30 (4:28 pace).