Abstract

Physical activity in the normal population is characterized by instability and fluctuation. Often people start an activity such as volleyball with much enthusiasm, they are full of enjoyment about the rediscovered bodily experiences they have missed for a long time, and they wonder why they have not begun this activity much earlier. However, after two or three months the enthusiasm has calmed down. The weekly activity times have lost their sacrosanct character. Alternative behaviors (e.g., watching TV, meeting friends) suddenly reoccur in one's mind. Finally the question is brought up whether all these exercise-related expenditures (far distance to the gymnasium, management of baby-sitting, financial costs etc.) outweigh the benefits of one's volleyball participation. And after all, some of the team members are strange anyway and I am not sure whether I really fit into this group... The first step to dropout has been made. Dropout does not happen all of a sudden, not from one day to the next, but is mentally and emotionally prepared over a longer period of time. During this period the exercise behavior is still shown at least sporadically, because the person is not yet ready to admit (to himself/herself or to others) that he or she has actually lost the initial interest in the activity. However, the motivational basis for continuing exercise participation has become so weak that the behavior has no chance to concur with attractive behavioral alternatives. In the end an interesting TV-program may be sufficient to forget about today's exercise intentions. In order to prevent dropout and to develop effective exercise promoting programs it is necessary to have a clear understanding of the psychological factors and mechanisms that lead to a continuous sport involvement. The better one knows the motivational and volitional processes underlying initiation, maintenance and eventually termination of physical activity participation, the better the chances that intervention efforts may be successful. The starting point of the present paper therefore is the question: What is psychology's contribution to describe and explain the behavior of physical activity? Aus der Einleitung