Simplify the following text for a Grade 6 native English-speaking person.
Original: The injured reserve list is a list of reserved players who are injured and unable to play for a period of time , used most prominently in the National Hockey League ( NHL ) and National Football League ( NFL ) .
Simplified: The injured reserve list is a list of players who are injured and can not play for a period of time . It is mostly used in the National Hockey League and National Football League .