i'ma be runnin' track this spring...

so far i've gotten recommendations such as cross-training and other things, but i was looking for a routine that could boost my speed within 5 months and still keep me lean and defined on the UB. i've tried looking through the site, but i always get lost on y'alls vocab: "splits" (what are those anyway?)... diet recommendations? can i get any recommendations or links to routines? and what supplements would be good for this?

height- 6'3/4"
weight- 178 lbs.
BF%- 16%