Self-Efficacy, Planning, or a Combination of Both? A Longitudinal Experimental Study Comparing Effects of Three Interventions on Adolescents’ Body Fat

• Aleksandra Luszczynska ,

  * E-mail: aluszczy@uccs.edu

  Affiliations Department of Psychology, SWPS University of Social Sciences and Humanities, Wroclaw, Poland, Trauma, Health, & Hazards Center, University of Colorado at Colorado Springs, Colorado Springs, CO, United States of America

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• Martin S. Hagger,

  Affiliations Health Psychology and Behavioural Medicine Research Group, School of Psychology and Speech Pathology, Curtin University, Perth, Australia, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland

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• Anna Banik,

  Affiliation Department of Psychology, SWPS University of Social Sciences and Humanities, Wroclaw, Poland

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• Karolina Horodyska,

  Affiliation Department of Psychology, SWPS University of Social Sciences and Humanities, Wroclaw, Poland

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• Nina Knoll,

  Affiliation Department of Education and Psychology, Freie Universität Berlin, Berlin, Germany

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• Urte Scholz

  Affiliation Department of Psychology, University of Zurich, Zurich, Switzerland

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