I signed up for a Foot Locker account. Do I need to also sign up for FLX Rewards? Yes. Sign up for a FLX Rewards account to enjoy all the benefits of membership. Related articles I joined FLX Rewards at Foot Locker. May I still use my benefits at Champs Sports? How do I manage my FLX Rewards account? What is FLX Rewards? What are the full FLX Program membership terms and conditions? How long do I have to validate my FLX Rewards account?