An experimental test of control theory-based interventions for physical activity.

Area of Science:

• Behavioral science
• Health psychology
• Exercise science

Background:

• Interventions using more control theory techniques correlate with better health behavior changes.
• Previous reviews lacked studies explicitly based on control theory.

Purpose of the Study:

• To experimentally test control theory's effectiveness in promoting physical activity.
• To assess the cumulative effects of behavior change techniques derived from control theory.

Main Methods:

• 124 participants were randomized into three groups: goal-setting only (GS), goal-setting + self-monitoring (GS+SM), and GS+SM+feedback (GS+SM+F).
• Physical activity was measured using accelerometers and self-report over a 7-day period.
• The study used a parallel groups, simple randomized design.

Main Results:

• The GS+SM+F group showed significantly greater total physical activity than the GS group (d=0.62) and marginally greater than the GS+SM group (d=0.33) on accelerometer measures.
• Feedback was most effective for individuals with weaker baseline intentions.
• Self-report measures did not show these patterns, but indicated feedback increased 'coasting' behavior initially.

Conclusions:

• Behavior change techniques aligned with control theory can yield short-term, objective improvements in physical activity.
• Intervention targeting all feedback loop aspects of control theory promotes greater change.
• Further research is needed to fully understand the underlying theoretical principles.