 One @-@ day track and field meetings form the most common and seasonal aspect of the sport – they are the most basic level of track and field competition . Meetings are generally organised annually either under the patronage of an educational institution or sports club , or by a group or business that serves as the meeting promoter . In the case of the former , athletes are selected to represent their club or institution . In the case of privately run or independent meetings , athletes participate on an invitation @-@ only basis . 
