title: Harnessing motivational forces in the promotion of physical activity: the Community Health Advice by Telephone (CHAT) project.
abstract: Physical inactivity among middle- and older-aged adults is pervasive, and is linked with numerous chronic conditions that diminish health and functioning. Counselor-directed physical activity programs may enhance extrinsic motivation (reflected in social influence theories, such as self-presentation theory) and, in turn, physical activity adherence, while the counselor is in charge of program delivery. However, external influences can undermine intrinsic motivation, making it more difficult to maintain physical activity once counselor-initiated contact ends. In contrast, programs that diminish the socially evaluative and controlling aspects of the counseling interchange may promote intrinsic motivation (described in cognitive evaluation theory), and, thus, physical activity maintenance, even when counselor-initiated contact ceases. The objective of the Community Health Advice by Telephone (CHAT) project is to compare these two theories by conducting a randomized controlled trial evaluating the effects of a telephone-administered counseling program delivered by a person (social influence enhancement) or computer (cognitive evaluation enhancement) on physical activity adoption and maintenance over 18 months. Healthy, sedentary adults (n = 225) aged 55 years and older are randomized to one of these programs or to a control arm. This study will contribute to advancing motivational theory as well as provide information on the sustained effectiveness of interventions with substantial public health applicability.
authors.affiliation: Department of Health Research & Policy, Stanford University School of Medicine, CA 94304-1583, USA.
authors.forename: Abby C
authors.initials: AC
authors.lastname: King
authors.forename: Robert
authors.initials: R
authors.lastname: Friedman
authors.forename: Bess
authors.initials: B
authors.lastname: Marcus
authors.forename: Cynthia
authors.initials: C
authors.lastname: Castro
authors.forename: LeighAnn
authors.initials: L
authors.lastname: Forsyth
authors.forename: Melissa
authors.initials: M
authors.lastname: Napolitano
authors.forename: Bernardine
authors.initials: B
authors.lastname: Pinto
mesh_terms: D000368:Aged; D003376:Counseling; D015444:Exercise; D006293:Health Promotion; D006801:Humans; D008875:Middle Aged; D008962:Models, Theoretical; D009042:Motivation; D016032:Randomized Controlled Trials as Topic; D012107:Research Design; D013689:Telephone