Here you can find an R script that gets the historic results of the Chicago Marathon.
data.table is an R package that provides an extension of data.frame object called data.table. The package was developed by M Dowle, T Short, S Lianoglou, A Srinivasan with contributions from R Saporta, E Antonyan and offers:
_Fast aggregation of large data
_Fast ordered joins
_Fast modify/add/delete columns
_Fast file reader
You can read more information about it here
and my simple summary here