Simmons (hamstring) was a limited participant in Thursday's practice, Jim Wyatt of the Titans' official site reports.
Simmons sat out practice Wednesday, so to see him upgrade to limited reps is a positive sign. The standout pass rusher hasn't played since Week 7 due to a lingering hamstring issue. The extent of his practice activity Friday may determine Simmon's availability, or lack thereof, for Sunday's home game against Houston.