A.M. No pain when I got up so I went out for a run on the cycle path. 2k warm then 4 x 2k at M.P. with 1,6 easy inbetween. Played gauge the pace game, my aim for the 2k's was 8:24-8:30 and without looking at the garmin I hit 8:21, 8:13, 8:15, 8:20. Not so far out. Finished with 4k cooldown which was when my left hamstring started hurting. Afterwards the muscle is sore and painful again :-( Total 18,8 in 1:26:50, av pace 4:37/k, 7:26/mi.