Date of Graduation
Master of Science in Kinesiology (MS)
Health, Human Performance and Recreation
Mathew S. Ganio
Second Committee Member
Psychology; Health and environmental sciences; Body size; Green exercise; Mood state; Obesity
Exercising in the presence of nature (i.e., "green exercise"), has been shown to heighten the physiological and mental benefits of traditional exercise on non-obese individuals. The effects of green exercise on obese individuals are unknown. It is hypothesized that green exercise is more beneficial for obese (greater positive improvements in mental health scores), compared to non-obese individuals. For example, the benefits of green exercise could help lower feelings of depression, improve mood and self-esteem to increase the propensity of obese individuals to meet exercise recommendations. Accordingly, this study investigated the physiological and psychological effects of green exercise on 12 obese (body mass: 90.0 ± 15.4 kg, body fat: 29.0 ± 8.6 %) and 10 non-obese (body mass: 76.6 ± 8.1 kg, body fat: 12.7 ± 2.5 %,) males. Subjects viewed either 30 previously-validated pleasant images of a rural setting (green exercise) or a blank screen (control) while walking for 30-minutes at a moderate intensity (50% of heart rate reserve). Mental health questionnaires (Adult Mental Health Continuum Short Form, Satisfaction with Life, Profile of Mood States, Exercise Self Efficacy, and Beck's Inventory) were completed pre- and post-exercise. Independent of subject groups, the control trial, versus green exercise, resulted in greater rating of perceived exertion (RPE; Control: 11 ± 0 vs Green Exercise: 10 ± 0; P = 0.006) and heart rate (Control: 126 ± 1 bpm, Green Exercise: 124 ± 2 bpm; P = 0.042). Independent of condition, obese individuals had significantly lower pre-exercise self-efficacy than non-obese (Non-obese: 46 ± 4; Obese: 33 ± 3, P = 0.017). Non-obese versus obese individuals had significantly greater improvements in overall mental health scores, as indicated by the MHC-SF Continuous category scores, regardless of condition (change from pre- to post-exercise in Non-obese: 6 ± 2; Obese: 0 ± 2; P = 0.041). Non-obese individuals had significantly greater improvements in the confusion-bewilderment mood state, independent of condition (post-
pre Obese: 0 ± 1; Non-obese: -2 ± 1; P = 0.019). Independent of body size, control exercise also significantly improved emotional health scores (MHC-SF Emotional category) more than the green exercise (Control: 1 ± 2; Green: 0 ± 2; P = 0.049). In conclusion, this data shows differences between obese and non-obese individuals when they exercise. Green exercise can lower RPE and HR in obese and non-obese individuals, and there is evidence to suggest that green exercise has important mental health benefits. However, improvements observed with green exercise were independent of body size, suggesting that green exercise is beneficial for non-obese and obese individuals.
Lachance, Alexandra, "Effect of Body Size and Exercise on Mood State" (2012). Theses and Dissertations. 631.