Group Identification
Group identification is the extent to which a person takes one specific group to be part of who they are, rather than a set of people they happen to be near. It is the narrow construct inside social identity theory, and in the exercise evidence it behaves very differently from the broad measures it usually gets averaged with. Generic social support, perceived cohesion and general belonging predict attendance poorly. Identification with a particular group, together with social attraction to it and social integration into it, predicted adherence in Xiaoxue Gao and colleagues' 2026 review where those broad scores did not.
What it is
The distinction matters because the two are routinely measured as though they were the same thing. A person can agree strongly that they enjoy the atmosphere in a class and hold no identification with the class at all, and the first tells you almost nothing about whether they will be there in March.
Identification descends from social identity theory, Tajfel and Turner's account from 1979, rather than from any single paper that coined the term, and the exercise-specific instruments are later and various. That attribution is recorded here at medium confidence rather than stated flatly, because nobody in this vault has yet traced the measure used in the group fitness literature back to a named scale.
Identification is to a group what exercise identity is to a person. Both ask whether something has been absorbed into the self-concept rather than merely done. Entitativity is the property on the group's side that makes identification possible at all, whether the thing reads as one bounded object rather than a collection of people, and identity fusion is the far end of the same continuum.