Cunningham worked out for the Lions on Tuesday, Aaron Wilson of the Houston Chronicle reports.
Cunningham was originally released by the Jaguars on Aug. 11. Tuesday's workout is important for the 29-year-old because it means he's clear of the hamstring injury that plagued him early in training camp. Detroit already has four healthy running backs on its active roster, but Cunningham could find a spot on the practice squad if he impresses the team Tuesday.