1. C.J. Caspersen, P.E. Kenneth, C.M. Gregory, Physical activity, exercise, and physical fitness: definitions and distinctions for health-related research. Public Health Rep. 100(2), 126 (1985)
2. Y. Chen, An economic analysis of decisions on physical activity and energy imbalance: cross-sectional evidence from a panel of middle-aged adults. Graduate Theses and Dissertations. 10732 (2009). http://lib.dr.iastate.edu/etd/10732
3. A Bulk-Binschoten, C.M. Renders, F.J.M Leerdam, R.A.. van,Hirasing, Transitional plan for children with overweight. Method for individual primary and secondary prevention in Youth Health Care, Dutch (2005)
4. J. Buckworth, Exercise adherence in college students: issues and preliminary results. Quest 53, 335–345 (2001). http://doi.org/10.1080/00336297.2001.10491750
5. W.A. Zatoński, HEM project team, Epidemiological analysis of health situation development in Europe and its causes until 1990. Ann. Agric. Environ. Med. 18(2), 194–202 (2011)