I started running 16 months ago. I'm 36 :) am I being ridiculous in aiming for a sub 17 5k by the beginning of winter this year?
My progression:
Dec 2012 - couldn't run a mile.
Feb 2013 - 24min 5k
Mid. 2013 - sub 20 5k
April 2014 - 18:35
June 2014 - 17:55
I train 5 days/week - 35-40 miles total. 2 interval sessions , 1 long run (10 miles) and 2 tempo runs ( usually 10k for these ). No injuries so far ;)
P.S. I wish I could turn back the clock and have started running 10 or 20 years ago :(