Strong evidence suggests that exercise and eating behaviours are strongly linked. Theory of Planned Behaviour is a theoretical framework that has been successfully used to explain and predict both behaviours. The aim of the present study is to explore the constructs of Theory of Planned Behavior (TPB) that better predicts exercise and healthy eating: a) intentions and b) self- reported behaviors among normal weight and overweight/obese adults. Participants were 361 adults in Greece (women: N = 152). According to their BMI scores, they have been grouped into normal weight and overweight/obese. Data were collected with an online questionnaire assessing variables of the theory of planned behavior (TPB) toward exercise and healthy eating intentions and behaviors. Correlations between the variables of TPB and behaviors (healthy eating and exercise) were higher in the normal weight group than in the overweight/obese group. The strongest predictor of intention to exercise was perceived behavioral control for both groups with the overweight/obese group showing higher values in comparison to normal weight group values. The same associations emerged for the prediction of intention for healthy eating behavior. The attitude was also a statistically significant predictor for both groups with higher values in normal weight group. The strongest predictor of exercise behavior was the intention, whereas for eating behavior significant predictors were attitudes, intentions and perceived behavioral control. TPB framework explained both intentions and behaviors for exercise and healthy eating of normal weight and overweight/obese adults. Initial information on which TPB constructs explain better intentions and behaviors by group implied that normal weight group has more positive exercise and healthy eating attitudes and intentions than the overweight/obese group; the behaviors of the overweight/obese group were explained better by perceived behavioral control. The above information can be used to design more effective interventions that aim to produce changes in both behaviors.
KeywordsTheory of Planned BehaviorExercise BehaviorHealthy Eating BehaviorNormal WeightOverweight
Adriaanse, M., Vinkers, C., De Ridder, D., Hox, J., & De Wit, J. (2011). Do Implementation Intentions Help to Eat a Healthy Diet? A Systematic Review and Meta-Analysis of the Empirical Evidence. Appetite, 56, 183-193. http://dx.doi.org/10.1016/j.appet.2010.10.012
Ajzen, I. (1985). From Intentions to Actions: A Theory of Planned Behavior. In J. Kuhl, & J. Beckmann (Eds.), Action Control, Social Psychology (pp. 11-39). Berlin: Springer. http://dx.doi.org/10.1007/978-3-642-69746-3_2
Ajzen, I. (1988). Attitudes, Personality, and Behavior. Chicago: IL: Dorsey.
Ajzen, I. (2002). Constructing a TpB Questionnaire: Conceptual and Methodological Considerations. http://www.uni-bielefeld.de/ikg/zick/ajzen%20construction%20a%20tpb%20questionnaire.pdf
Ajzen, I. (1991). The Theory of Planned Behavior. Organizational Behavior and Human Decision Processes, 50, 179-121. http://dx.doi.org/10.1016/0749-5978(91)90020-T
Ajzen, I. (2011). The Theory of Planned Behaviour: Reactions and Reflections. Psychology & Health, 26, 1113-1127. http://dx.doi.org/10.1080/08870446.2011.613995
Ajzen, I., & Manstead, A. (2007). Changing Health-Related Behaviors: An Approach Based on the Theory of Planned Behavior. In J. D. M. Hewstone (Ed.), The scope of social psychology: Theory and applications (pp. 43-63). New York: Psychology Press.
Albarracin, D. J. (2001). Theories of Reasoned Action and Planned Behavior as Models of Condom Use. Psychological Bulletin, 127, 142-161. http://dx.doi.org/10.1037/0033-2909.127.1.142
Amireault, S., Godin, G., Vohl, M. C., & Pérusse, L. (2008). Moderators of the Intention-Behaviour and Perceived Behavioural Control-Behaviour Relationships for Leisure-Time Physical Activity. International Journal of Behavioral Nutrition and Physical Activity, 5, 7. http://dx.doi.org/10.1186/1479-5868-5-7
Armitage, C., & Conner, M. (2001). Efficacy of the Theory of Planned Behaviour: A Meta-Analytic Review. British Journal of Social Psychology, 40, 471-499. http://dx.doi.org/10.1348/014466601164939
Armitage, C., & Cornner, M. (1999). Distinguishing Perceptions of Control from Self-Efficacy: Predicting Consumption of a Low-Fat Diet Using the Theory of Planned Behavior. Journal of Applied Social Psychology, 29, 72-90. http://dx.doi.org/10.1111/j.1559-1816.1999.tb01375.x
Arnow, B. K. (1995). The Emotional Eating Scale: The Development of a Measure to Assess Coping with Negative Affect by Eating. International Journal of Eating Disorders, 18, 79-90. http://dx.doi.org/10.1002/1098-108X(199507)18:1 3.0.CO;2-V
?str?m, A., & Rise, J. (2001). Young Adults’ Intention to Eat Healthy Food: Extending the Theory of Planned Behaviour. Psychology & Health, 16, 223-237. http://dx.doi.org/10.1080/08870440108405501
Bebetsos, E., Chroni, S., & Theodorakis, Y. (2002). Physical Active Students’ Intentions and Self-Efficacy towards Healthy Eating. Psychological Reports, 91, 485-495.
Bebetsos, E., Theodorakis, I., Laparidis, K., & Chroni, S. (2000). Reliability and Validity of a Self-Confidence Scale for a Healthy Eating Questionnaire. Health and Sport Performance, 3, 191-203. (In Greek)
Boudreau, F., & Godin, G. (2007). Using the Theory of Planned Behaviour to Predict Exercise Intention in Obese Adults. Canadian Journal of Nursing Research, 39, 112-125.
Bozionelos, G. (1999). The Theory of Planned Behaviour as Predictor of Exercise. Journal of Health Psychology, 4, 517-529. http://dx.doi.org/10.1177/135910539900400406
Bray, G. A., & Bouchard, C. (2014). Handbook of Obesity: Epidemiology, Etiology, and Physiopathology. Boca Raton: CRC Press. http://dx.doi.org/10.1201/b16473
Catellier, A., & Yang, Z. (2013). The Role of Affect in the Decision to Exercise: Does Being Happy Lead to a More Active Lifestyle? Psychology of Sport and Exercise, 14, 275-282. http://dx.doi.org/10.1016/j.psychsport.2012.11.006
Clark, J. (2015). Diet, Exercise or Diet with Exercise: Comparing the Effectiveness of Treatment Options for Weight-Loss and Changes in Fitness for Adults (18-65 Years Old) Who Are Overfat, or Obese; Systematic Review and Meta-Analysis. Journal of Diabetes & Metabolic Disorders, 14, 31.
Conner, M., Norman, P., & Bell, R. (2002). The Theory of Planned Behavior and Healthy Eating. Health Psychology, 21, 194-201. http://dx.doi.org/10.1037/0278-6133.21.2.194
Connolly, C., Romano, T., & Patruno, M. (1998). Effects of Dieting and Exercise on Resting Metabolic Rate and Implications for Weight Management. Family Practice, 16, 196-201.
Deforche, B., De Bourdeaudhuij, I., & Tanghe, A. (2006). Attitude toward Physical Activity in Normal-Weight, Overweight and Obese Adolescents. Journal of Adolescent Health, 38, 560-568. http://dx.doi.org/10.1016/j.jadohealth.2005.01.015
Gardner, R., & Hausenblas, H. (2005). Exercise and Diet Determinants of Overweight Women Participating in an Exercise and Diet Program: A Prospective Examination of the Theory of Planned Behavior. Women & Health, 42, 37-62. http://dx.doi.org/10.1300/J013v42n04_03
Gelman, A. H. (2006). Data Analysis Using Regression and Multilevel/Hierarchical Models. Cambridge: Cambridge University Press. http://dx.doi.org/10.1017/cbo9780511790942
Ghahremani, L., Niknami, S., & Nazari, M. (2012). The Prediction of Physical Activity Intention and Behavior in Elderly Male Residents of a Nursing Home: A Comparison of Two Behavioral Theories. Iranian Journal of Medical Sciences, 37, 23-31.
Godin, G., & Kok, G. (1996). The Theory of Planned Behavior: A Review of Its Applications to Health-related Behaviors. American Journal of Health Promotion, 11, 87-98. http://dx.doi.org/10.4278/0890-1171-11.2.87
Godin, G., & Shephard, R. (1985). A Simple Method to Assess Exercise Behavior in the Community. Canadian Journal of Applied Sport Sciences, 10, 141-146.
Godin, G., Amireault, S., Bélanger-Gravel, A., Vohl, M., & Pérusse, L. (2009). Prediction of Leisure-Time Physical Activity Among Obese Individuals. Obesity, 17, 706-712. http://dx.doi.org/10.1038/oby.2008.599
Godin, G., Bélanger-Gravel, A., & Nolin, B. (2008). Mechanism by Which BMI Influences Leisure-Time Physical Activity Behavior. Obesity (Silver Spring), 16, 1314-1317. http://dx.doi.org/10.1038/oby.2008.219
Godin, G., Bélanger-Gravel, A., Vohl, M., & Pérusse, L. (2011). The Effect of Mere-Measurement of Cognitions on Physical Activity Behavior: A Randomized Controlled Trial among Overweight and Obese Individuals. International Journal of Behavioral Nutrition and Physical Activity, 8, 2. http://dx.doi.org/10.1186/1479-5868-8-2
Gr?nh?j, A., Bech-Larsen, T., Chan, K., & Tsang, L. (2013). Using Theory of Planned Behavior to Predict Healthy Eating Among Danish Adolescents. Health Education, 113, 4-17. http://dx.doi.org/10.1108/09654281311293600
Guillaumie, L., Godin, G., & Vezina-Im, L. (2010). Psychosocial Determinants of Fruit and Vegetable Intake in Adult Population: A Systematic Review. International Journal of Behavioral Nutrition and Physical Activity, 7, 12. http://dx.doi.org/10.1186/1479-5868-7-12
Hagger, M., Chatzisarantis, N., & Biddle, S. (2002). A Meta-Analytic Review of the Theories of Reasoned Action and Planned Behavior in Physical Activity Q Predictive Validity and the Contribution of Additional Variables. Exercise Psychology, 24, 3-32.
Hardeman, W., Johnston, M., Bonetti, D., Wareham, N., & Kinmonth, A. (2002). Application of the Theory of Planned Behaviour in Behaviour Change Interventions: A Systematic Review. Psychology & Health, 17, 123-158. http://dx.doi.org/10.1080/08870440290013644a
Hassandra, M., Vlachopoulos, S., Kosmidou, E., Hatzigeorgiadis, A., Goudas, M., & Theodorakis, Y. (2011). Predicting Students’ Intention to Smoke by Theory of Planned Behaviour Variables and Parental Influences across School Grade Levels. Psychology & Health, 26, 1241-1258. http://dx.doi.org/10.1080/08870446.2011.605137
Hearty, A., McCarthy, S., Kearney, J., & Gibney, M. (2007). Relationship between Attitudes towards Healthy Eating and Dietary Behaviour, Lifestyle and Demographic Factors in a Representative Sample of Irish Adults. Appetite, 48, 1-11. http://dx.doi.org/10.1016/j.appet.2006.03.329
Hill, J. P. (1998). Environmental Contributions to the Obesity Epidemic. Science, 280, 1371-1374. http://dx.doi.org/10.1126/science.280.5368.1371
Hyde, A. L., Conroy, D. E., & Pincus, A. L. (2011). Unpacking the Feel-Good Effect of Free-Time Physical Activity: Between- and Within-Person Associations with Pleasant—Activated Feeling States. Journal of Sport and Exercise Psychology, 33, 884-902.
Karvinen, K., Courneya, K., Campbell, K., Pearcey, R., Dundas, G., Capstick, V. et al. (2007). Correlates of Exercise Motivation and Behavior in a Population-Based Sample of Endometrial Cancer Survivors: An Application of the Theory of Planned Behavior. International Journal of Behavioral Nutrition and Physical Activity, 4, 21. http://dx.doi.org/10.1186/1479-5868-4-21
Kim, K., Reicks, M., & Sjoberg, S. (2003). Applying the Theory of Planned Behavior to Predict Dairy Product Consumption by Older Adults. Journal of Nutrition Education and Behavior, 35, 294-301. http://dx.doi.org/10.1016/s1499-4046(06)60343-6
McClure, A., Tanski, S., Kingsbury, J., Gerrard, M., & Sargent, J. (2010). Characteristics Associated with Low Self-Esteem among US Adolescents. Academic Pediatrics, 10, 238-244. http://dx.doi.org/10.1016/j.acap.2010.03.007
McEachan, R., Conner, M., Taylor, N., & Lawton, R. (2011). Prospective Prediction of Health-Related Behaviours with the Theory of Planned Behaviour: A Meta-Analysis. Health Psychology Review, 5, 97-144. http://dx.doi.org/10.1080/17437199.2010.521684
Michie, S., Ashford, S., Sniehotta, F., & Dombrowski, S. (2011). A Refined Taxonomy of Behaviour Change Techniques to Help People Change Their Physical Activity and Healthy Eating Behaviours: The CALO-RE Taxonomy. Psychology Health, 26, 1479-1498. http://dx.doi.org/10.1080/08870446.2010.540664
Miller, W., & Miller, T. (2010). Attitudes of Overweight and Normal Weight Adults Regarding Exercise at a Health Club. Journal of Nutrition Education and Behavior, 42, 2-9. http://dx.doi.org/10.1016/j.jneb.2008.08.005
Mogre, V., Nyaba, R., Aleyira, S., & Sam, N. (2015). Demographic, Dietary and Physical Activity Predictors of General and Abdominal Obesity among University Students: A Cross-Sectional Study. Springerplus, 4, 226. http://dx.doi.org/10.1186/s40064-015-0999-2
Nestle, M. P. (2013). How the Food Industry Influences Nutrition and Health. Oakland, CA: University of California Press.
Norman, P. C. (1999). The Theory of Planned Behavior and Smoking Cessation. Health Psychology, 18, 89-94. http://dx.doi.org/10.1037/0278-6133.18.1.89
?ygard, L., & Rise, J. (1996). Predicting the Intention to Eat Healthier Food among Young Adults. Health Education Research, 11, 453-461. http://dx.doi.org/10.1093/her/11.4.453
Payne, N., Jones, F., & Harris, P. (2004). The Role of Perceived Need within the Theory of Planned Behaviour: A Comparison of Exercise and Healthy Eating. British Journal of Health Psychology, 9, 489-504. http://dx.doi.org/10.1348/1359107042304524
Payne, N., Jones, F., & Harris, P. (2005). The Impact of Job Strain on the Predictive Validity of the Theory of Planned Behaviour: An Investigation of Exercise and Healthy Eating. The British Psychological Society, 10, 115-131. http://dx.doi.org/10.1348/135910704x14636
Plotnikoff, R., Lubans, D., Costigan, S., & McCargar, L. (2013). A Test of the Theory of Planned Behavior to Predict Physical Activity in an Overweight/Obese Population Sample of Adolescents from Alberta, Canada. Health Education and Behavior, 40, 415-425. http://dx.doi.org/10.1177/1090198112455642
Povey, R., Conner, M., Sparks, P., James, R., & Shepherd, R. (2000). The Theory of Planned Behaviour and Healthy Eating: Examining Additive and Moderating Effects of Social Influence Variables. Psychology & Health, 14, 991-1006. http://dx.doi.org/10.1080/08870440008407363
Psouni, S., Hassandra, M., & Theodorakis, Y. (2016). Patterns of Eating and Physical Activity Attitudes and Behaviors in Relation to Body Mass Index. Psychology, 7, 180-192. http://dx.doi.org/10.4236/psych.2016.72020
Puhl, R., & Heuer, C. (2009). The Stigma of Obesity: A Review and Update. Obesity, 17, 941-964. http://dx.doi.org/10.1038/oby.2008.636
Rhodes, E., & Dickau, L. (2013). Moderators of the Intention-Behavior Relationship in the Physical Activity Domain: A Systematic Review. British Journal of Sports Medicine, 47, 215-225. http://dx.doi.org/10.1136/bjsports-2011-090411
Rivis, A., & Sheeran, P. (2003). Descriptive Norms as an Additional Predictor in the Theory of Planned Behavior: A Meta-Analysis. Current Psychology Developmental, Learning, Personality, Social, 22, 218-233.
Rothman, K.J. (2008). BMI-Related Errors in the Measurement of Obesity. International Journal of Obesity, 3, 56-59. http://dx.doi.org/10.1038/ijo.2008.87
Schifter, D., & Ajzen, I. (1985). Intention, Perceived Control, and Weight Loss: An Application of the Theory of Planned Behavior. Journal of Personality and Social Psychology, 49, 843-851. http://dx.doi.org/10.1037/0022-3514.49.3.843
Sjoberg, S., Kim, K., & Reicks, M. (2004). Applying the Theory of Planned Behavior to Fruit and Vegetable Consumption by Older Adults. Journal of Nutrition for the Elderly, 23, 35-46. http://dx.doi.org/10.1300/J052v23n04_03
Sutton, S. (1998). Predicting and Explaining Intentions and Behavior: How Well Are We Doing? Journal of Applied Social Psychology, 28, 1317-1338. http://dx.doi.org/10.1111/j.1559-1816.1998.tb01679.x
Theodorakis, Y. (1994). Planned Behavior, Attitude Strength, Role Identity, and the Prediction of Exercise Behavior. Sport Psychologist, 8, 149-165.
Thomas, E. L., Frost, G., Taylor-Robinson, S. D., & Bell, J. D. (2012). Excess Body Fat in Obese and Normal-Weight Subjects. Nutrition Research Reviews, 25, 150-161. http://dx.doi.org/10.1017/S0954422412000054
Trudeau, E., Kristal, A., Li, S., & Patterson, S. (1998). Demographic and Psychosocial Predictors of Fruit and Vegetable Intakes Differ: Implications for Dietary Interventions. Journal of the American Dietetic Association, 98, 1412-1417. http://dx.doi.org/10.1016/S0002-8223(98)00319-8
Verplanken, B., & Faes, S. (1999). Good Intentions, Bad Habits, and Effects of Forming Implementation Intentions on Healthy Eating. European Journal of Social Psychology, 29, 591-604. http://dx.doi.org/10.1002/(SICI)1099-0992(199908/09)29:5/6 3.0.CO;2-H
Wing, R., & Phelan, S. (2005). Long-Term Weight Loss Maintenance1,2,3,4. American Journal of Clinical Nutrition, 82, 222S-225S.