Health Promotion in Multiple Domains: Capitalizing on the Spillover Effect

Introduction: Simultaneous intervention on multiple health behavior change (MHBC remains the current focus of preventive medicine research (de Vries et al., 2008; Prochaska et al., 2008). The spillover effect (Nigg et al., 2002) may provide utility in a self-regulation based MHBC intervention supplemented with mindfulness and self-efficacy training. The spillover effect occurs when intervention on one behavior (e.g., exercise) provides a protective spillover effect unto one or more alternate health behaviors (e.g., diet). The impetus for the application of the spillover effect in a self-regulation MHBC framework is threefold: 1) self-regulation of behaviors focused on one behavior limits ego depletion; 2) initially requires less energy compared to simultaneous behavior change; and 3) minimal resources if behavior change skills are transferrable (e.g., Oaten & Cheng, 2006; Paiva et al., 2012).

Method: Female university students (N=30) were asked to complete baseline and one-month follow-up surveys; a subsample (N=20) was randomly selected to additionally complete daily diaries over the study period. The online intervention included the following techniques for the spillover effect (exercise) and simultaneous MHBC (exercise, fruit/ vegetable consumption) conditions: 1) goal setting; 2) mental contrasting; 3) self-regulation practice; 4) mindfulness practice; and 5) positive self-talk. Outcome variables included self-regulation, impulsivity, self-efficacy, positive/ negative affect, fruit/ vegetable consumption, and exercise.

Results: In the pre-post sample, a greater portion of the spillover effect condition reported improvement in global self-regulation, exercise self-regulation, eating self-regulation, self-efficacy, aerobic exercise, fruit servings, vegetable servings and variety, weight loss/maintenance, sleep, and electronic media use compared to the traditional MHBC condition. The daily diaries revealed that a greater portion of the traditional MHBC condition reported improvements in self-efficacy, and vegetable variety/ servings compared to a greater portion of spillover effect condition that reported increases in fruit variety, sleep, and positive affect.

Conclusions: Despite limited significance, descriptive statistics indicated that the spillover effect condition performs equally or better than the simultaneous intervention for many of the outcomes. Given the increasing comorbidity rates of preventable health problems and the amount of resources expended for treatment, the benefits of MHBC interventions targeted at comorbid risk behaviors cannot be overstated (de Vries et al., 2008; Prochaska, 2008). Targeting unhealthy lifestyle behaviors, such as sedentary behaviors in young adults may curtail the increasing risk for early mortality.