The psychological effects of exercise on dieting obese women

Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)




Michael P. Carey


Physiological psychology, Nutrition, Public health, Sports medicine

Subject Categories

Clinical Psychology


Obesity presents a significant threat to health and well-being. The purpose of this study was to determine psychological effects of a regular supervised exercise program in dieting women. Participants were 51 overweight women who volunteered for a comprehensive diet and exercise program and were randomized to one of four groups: (a) diet alone, (b) diet plus aerobic exercise, (c) diet plus resistance exercise, and (d) diet plus combined exercise. Changes in weight, dietary adherence, macronutrient preference, hunger, preoccupation with food, mood, perceived stress, self-esteem, and self-efficacy were assessed. At the end of 24 weeks, participants across the four groups lost an average of 19.3 $\pm$ 6.4 kg, reducing their initial body weight by 19.5 $\pm$ 6.1 percent. No significant differences were evident among conditions. Exercising participants (ex) were less adherent to the diet at weeks 4 and 16 than non-exercisers (new) (wk 4: ex 267 $\pm$ 528 vs. new 44 $\pm$ 105; wk 16: ex 1018 $\pm$ 1061 vs new: 345 $\pm$ 353). Kcal/d for all participants decreased significantly from 2199 $\pm$ 419 at baseline to 1458 $\pm$ 417 by week 24. Significant decreases in hunger (26%) and preoccupation with food (19%) were reported in the first four weeks and sustained throughout the trial. Increases in self-esteem (6%) and self-efficacy (8%) were reported. However, no effect for exercise was found on any of these variables. Exercising participants reported feeling more positively at weeks 8, 12, and 24 (wk 8: ex 34.9 $\pm$ 6.5 vs. new 30.4 $\pm$ 7.4; wk 12: ex 34.6 $\pm$ 6.8 vs. new 29.2 $\pm$ 7.7; wk 24: ex 35.7 $\pm$ 6.4 vs. new 30.5 $\pm$ 8.8) and less negatively at weeks 8 and 12 (wk 8: ex 15.8 $\pm$ 5.9 vs. new 20.2 $\pm$ 6.4; wk 12: ex 14.9 $\pm$ 5.2 vs. new 20.2 $\pm$ 5.6). Significant weight loss achieved through dieting results in improvements in energy balance, nutrient selection, and self-concept, along with decreases in hunger and interest in food. Adding exercise to an intensive weight loss program enhances mood although dietary compliance may be somewhat compromised.