"Sedentary behavior is associated with increased cancer risk, including endometrial cancer," said Karen Basen-Engquist, Ph.D., professor in the Department of Behavioral Science at MD Anderson and lead investigator on the study. "When cancer survivors exercise, it not only improves their physical functioning and psychological well-being, but also reduces their risk of developing other types of cancer or other chronic diseases."
In this study, funded by the National Cancer Institute, information was collected from 100 endometrial cancer survivors to measure self-efficacy -a person's belief in her ability to complete tasks and reach goals - and exercise duration. Additionally, researchers conducted routine laboratory cardiorespiratory fitness assessments of the participants. Researchers studied the relationship between self-efficacy and exercise behaviors over six months.
Self-efficacy was measured two ways. Study participants carried hand-held computers and every morning recorded their self-efficacy, or confidence, in completing recommended exercise, and also used the computer to record how long they exercised. They completed questionnaires every two months to measure self-efficacy.
A one point increase in self-efficacy led to six more minutes of exercise
Each participant received a personalized exercise recommendation based on guidelines from the American College of Sports Medicine. They also were given printed materials, a pedometer and access to telephone counseling to help them increase their amount of exercise.
Important findings of the study included the daily effect of self-efficacy on exercise duration. Higher self-efficacy in the morning was associated with significantly more moderate-to vigorous intensity exercise during the day. For every one point increase in self-efficacy, participants increased their exercise routine by six minutes.
Given that exercise is an important aspect of cancer survivorship and endometrial cancer patients are often overweight or obese and physically inactive, Basen-Engquist recommends any exercise, or increase in exercise, would benefit cancer patients and survivors.
"Our observations make a unique contribution to research by revealing a sense of how the self-efficacy-behavior relationship works outside the laboratory," said Basen-Engquist. "Our next step will be to determine if we can provide messages to cancer survivors in real time, using methods like email or smart phone applications, to increase their self-efficacy and encourage them to exercise more."
Basen-Engquist is the director of MD Anderson's new Center for Energy Balance in Cancer Prevention and Survivorship. The center, funded by MD Anderson and the Duncan Family Institute for Cancer Prevention and Risk Assessment, addresses the role of obesity, diet and exercise in cancer, while developing solutions to the country's obesity epidemic.