Browsing by Author "Dennis, Elizabeth A."

Now showing 1 - 3 of 3
  • Thumbnail Image
    The Efficacy of Increased Water Consumption as a Weight Loss Strategy
    Dennis, Elizabeth A. (Virginia Tech, 2010-04-02)
    The population of older adults continues to grow in the US, as does the prevalence of overweight and obesity within this group. Several factors may contribute to age-related weight gain, such as a reduced energy expenditure and energy intake requirements, and a susceptibility to energy over-consumption. Serious consequences result from overweight and obesity, such as increased risk of chronic disease, decreased quality of life and increased healthcare costs. Thus, effective weight management strategies are needed which target this population. Reducing energy-containing beverage intake and increasing water intake are often suggested as strategies for weight loss, yet surprisingly little data exists to support the effectiveness of these strategies. Previous studies have shown that older adults consume fewer calories at a laboratory test meal following a water preload, but it is unknown whether this reduced energy intake can be sustained over time to produce weight loss. Epidemiological studies using self-reported dietary intake have shown that substituting water for energy-containing beverages decreases total energy intake, and that drinking > 1L of water is associated with greater weight loss in overweight women compared to overweight women who consumed < 1L daily. However, these studies were a secondary analysis of a trial comparing multiple weight loss strategies and increasing water consumption was not a primary outcome of interest. To directly address this issue, we hypothesized that increased water consumption would increase weight loss in healthy overweight and obese older adults in combination with a 12-week hypocaloric diet as compared to a hypocaloric diet alone. As hypothesized, older adults randomized to the increased water intake group demonstrated greater weight loss than those randomized to the diet alone group (7.4 kg vs. 5.5 kg, respectively). Because energy-containing beverages contribute to total energy intake without a concomitant reduction in food intake, substituting water or energy-free beverages for energy-containing beverages appears to be an effective weight management strategy for older adults.
  • Thumbnail Image
    Feasibility, effectiveness, and perceptions of an Internet- and incentive-based behavioral weight loss intervention for overweight and obese college freshmen: A mixed methods approach
    Davy, Brenda M.; Potter, Kerry L.; Dennis, Elizabeth A.; Harden, Samantha M.; Hill, Jennie L.; Halliday, Tanya M.; Estabrooks, Paul A. (2013)
    Challenges inherent with the transition to col- lege are often accompanied by weight gain among college freshmen. Weight gain and dura- tion of obesity increase metabolic syndrome and cardiovascular disease risk in young adulthood, which supports the need for weight loss inter- ventions tailored to college students. The pur- pose of this investigation was to conduct a mixed methods pilot trial to determine the effi- cacy and acceptability of a semester long Inter- net- and incentive-based weight loss interven- tion for overweight/obese college freshmen. Par- ticipants (n = 27, aged >18 yrs, BMI >25) were randomly assigned to a 12-week social cognitive theory (SCT)-based intervention (Fit Freshmen [FF]) or a health information control group. The FF intervention also included modest financial incentives for weight loss. Primary outcomes included body weight/composition, dietary and physical activity (PA) behaviors, and psychoso- cial measures (i.e. self-efficacy, self-regulation) associated with diet, PA, and weight loss. Stu- dents in the FF intervention participated in focus groups to provide qualitative feedback on pro- gram structure and design. FF participants demonstrated significant reductions (all group differences p < 0.10) in body weight (−1.2 kg), fat mass (−0.6 kg), dietary energy (−673 kcal/d), fat (−37 g/d) and added sugar intake (−41 g/d), and increases in diet and PA-related self-regulatory skills at week 12 compared to control partici- pants (+1.0 kg, +1.1 kg, −334 kcal/d, −15 g/d, −13 g/d, respectively). No changes in PA were noted, but FF participants demonstrated increases in self-efficacy to overcome barriers to PA relative to control participants. Themes for content im- provement from focus groups included reducing email contact and increasing in-person interac- tions. Program characteristics that were posi- tively evaluated included incentives for weight loss and access to an onsite weigh station kiosk. Overall, this efficacious SCT Internet- and incen- tive-based weight loss intervention was well received and can be adapted for larger-scale use in the college population.
  • Thumbnail Image
    Weight Gain Prevention for College Freshmen: Comparing Two Social Cognitive Theory-Based Interventions with and without Explicit Self-Regulation Training
    Dennis, Elizabeth A.; Potter, Kerry L.; Estabrooks, Paul A.; Davy, Brenda M. (2012)
    The college transition represents a critical period for maintaining a healthy weight, yet intervention participation and retention represent significant challenges. The objective of this investigation was to evaluate the preliminary efficacy and acceptability of two interventions to prevent freshman weight gain. One intervention provided opportunities to improve outcome expectations and self-efficacy within a social cognitive theory framework (SCT), while the other targeted the same variables but focused on explicit training in self-regulation skills (SCTSR). Methods. Freshmen (n = 45) aged >18 years were randomized to a 14-week intervention, SCT or SCTSR; both included online modules and in-class meetings. Of the 45 students randomized, 5 withdrew before the classes began and 39 completed pre- and posttesting. Primary outcomes included body weight/composition, health behaviors, and program acceptability. Analyses included independent sample t-tests, repeated measures ANOVA, and bivariate correlational analyses. Results. Body weight increased over the 14-week period, but there was no group difference. Percent body fat increased in SCTSR but not SCT (mean difference: SCTSR, +1.63 ± 0.52%; SCT, -0.25 ± 0.45%; P = 0.01). Class attendance was 100% (SCTSR) and 98% (SCT); SCTSR students (>50%) remarked that the online tracking required "too much time." Conclusions. The intervention was well received, although there were no improvements in weight outcomes.