The main purpose of the study was to examine exercise behavior and motivation in customers of a web based exercise service institution. The study also aimed to derive implications for optimizing the web services regarding exercise motivation enhancement. The respondents (n=1262) were active members of www.tappa.se and data was collected through a web based survey containing a number of exercise oriented questionnaires; e.g. The Basic Psychological Needs in Exercise Scale, Barriers Self-Efficacy Scale, Physical Activity Stages of Change Questionnaire 2:1, The Behavioral Regulation in Exercise Questionnaire-2, etc. The results revealed respondents to have a generally self-determined motivation profile and to utilize goals focused on health management and image. Also, there were correlations between demographical aspects and several psychological variables. Conclusions involve recommendations to apply a theory foundation in the web service, preferably using self-determination, self-efficacy and stages of change references. Challenges in order to develop this kind of web service, as well as exercise promotion in general, are to reach Pre-contemplators, whom could be hard to reach. Furthermore, a refocus of the studied web service from weight control to health related aspects could have positive impact on motivation and could also attract more men. Regarding workplace health promotion, it is essential to invest in motivational and engagement supporting methods. Finally, it is generally recommended to use qualified exercise psychology competence in exercise promotion.