Dr. Unick is an Assistant Professor (Research) at the Warren Alpert Medical School at Brown University and an exercise physiologist at The Miriam Hospital's Weight Control and Diabetes Research Center. She received her PhD in exercise physiology from the University of Pittsburgh, where she also gained valuable experience in behavioral weight loss treatment. Her long-term goal is to become an independent exercise/obesity investigator, with a line of research focused on understanding the psychological factors through which exercise may assist in long-term weight control. The current application would add to the scant literature in this area by examining whether exercise reduces stress-induced overeating. An understanding of the basic mechanisms through which exercise influences weight control, is important for the future of obesity treatment. As part of this Mentored Research Scientist Development Award (K01), Dr. Unick will gain extensive training in the areas of (1) stress responses and stress methodology, (2) stress as it specifically affects obesity, (3) the psychological benefits of exercise as observed in the treatment of addictions, (4) ecological momentary assessment (EMA) and statistical analyses, (5) the responsible conduct of research, and (6) professional development focused on becoming an independent investigator. This training will occur in the form of didactics and hands-on experiences gained under the guidance and supervision of a highly qualified team of mentors. Dr. Unick will work closely with her primary mentor, Dr. Rena Wing, an internationally recognized obesity researcher, as well as her multidisciplinary team of co-mentors [Dr. Laura Stroud (stress methodology), Dr. Elissa Epel (stress and obesity), Dr. Rick Brown (exercise in addictions), and Drs. Ross Crosby and Graham Thomas (EMA and statistical analyses)]. The research will be conducted at The Miriam Hospital &Brown Medical School, an environment well-suited for developing junior investigators and fully equipped with the resources to carry out the proposed research plan. Given that stress contributes to overeating and poor dietary choices and a separate body of literature demonstrating that exercise reduces stress, the current application seeks to examine the novel question of whether exercise training reduces stress-induced eating. We will begin by examining this in a tightly controlled laboratory setting (Study 1) and then transition to the examination of this research question in a free-living environment (Study 2). In Study 1, 48 sedentary and overweight/obese women will be randomized to a 10- week supervised exercise training program (EX) or a no-exercise control condition (CON). Participants will come to the lab on two separate occasions at both baseline and 10 weeks. On one day they will be exposed to a psychosocial stressor while the other day will serve as a no-stress, control day. "Stress-induced eating" will be defined as the energy intake (measured via a buffet meal) following exposure to the stressor on the stress day minus the energy intake on the no-stress day. It is hypothesized that EX will reduce "stress-induced eating" relative to CON. Given that exposure to a psychosocial stressor and buffet meal in a laboratory setting may not mimic real world conditions, Study 2 will focus on whether exercise reduces stress-induced overeating using smart phones and EMA data collection methods, designed to obtain 'real-time'responses in a free living environment. Forty-eight sedentary, overweight/obese women will be randomized to 10 weeks of supervised exercise training (EX) or a no-exercise control condition (CON). Participants will be asked to log their stress, mood, hunger, dietary temptations/lapses, and "overeating" episodes via a smart phone for 10 days before and after the training period. It is hypothesized that EX will reduce the proportion of "overeating" and "stress-induced overeating" episodes, relative to CON. The proposed studies are the first to examine the effects of exercise training on stress-induced overeating, addressing an important research gap in the area of exercise and obesity. The rigorous methodology, randomized design, and novel use of dual methodologies (lab to life generalization) make this application both significant and innovative. Moreover, these studies will provide rich data sets, enabling Dr. Unick to conduct additional exploratory and hypothesis generating analyses, which will also help facilitate her transition to an independent investigator. It is expected that through the formal coursework, hands-on training, and excellent mentorship, Dr. Unick will gain the knowledge and skills necessary to develop an independent, extramurally funded research career in the area of exercise and obesity.
The proposed application is designed to assist Dr. Unick in developing an independent research career focused on understanding the psychological factors that mediate the effect of exercise on long-term weight control. Through the guidance and supervision from a superb team of mentors, Dr. Unick will gain valuable didactic and hands-on training in the areas of (1) stress responses and stress methodology, (2) the role of stress in obesity, (3) ecological momentary assessment (EMA) and statistical analyses, (4) the broader, psychological benefits of exercise observed in other health domains, and (5) randomized trials and the responsible conduct of research. The proposed research will be instrumental in advancing the exercise and obesity field, by examining whether exercise reduces overeating in response to stress, a novel mechanism through which exercise may act to control body weight.