This pilot study represents an initial foray into delivering an Individual Voice Response-based (IVR) physical activity intervention for cancer risk among sedentary adults in the Deep South.

60 participants will receive the DIAL intervention or Wait List Control. While main outcomes are focused on feasibility and acceptability, physical activity, fitness, and body weight and composition data will be collected and measured at baselines and 12-weeks.

DIAL Intervention: The physical activity intervention is based on Social Cognitive Theory and emphasizes behavioral strategies for increasing activity levels (i.e., goal setting, self-monitoring, problem solving barriers, increasing social support, rewarding oneself for meeting physical activity goals) and includes daily activity reporting via an Individual Voice Response (IVR) system that allows computer-assisted interaction with participants by telephone. Computer expert system feedback on physical activity progress will be based on participants' reported daily step counts and >moderate intensity PA . In addition to IVR system feedback, participants will receive monthly graphic-based feedback letters delivered by mail. Messages will encourage incremental increases until national PA guidelines are reached and provide specific information on cancer risk reduction ("In the past 7 days, you called the DIAL study line all 7 days and reported engaging in 80 minutes of moderate intensity PA. The national guidelines call for >150 min/week of moderate intensity PA so you are well on your way. Keep up the good work. Make small increases in PA each week until you reach that goal. Remember: 30-60 min/day of moderate-vigorous intensity PA may significantly lower your risk of breast and colon cancer").

To improve self-efficacy, social support, outcome expectations, and perceived enjoyment, we will assess these variables at baseline, 30, 60, and 90 days. Responses will be used to select appropriate tailored feedback modules (for low self-efficacy score, "You do not seem confident about your ability to exercise. Often trying to fit in some PA on top of the demands of work and family can be a challenge. Try making time for a 10 minute walk 1-2 days this week. It will help build confidence about your ability to fit PA into your lifestyle.") Finally, participants will receive access to problem solving modules, addressing PA barriers identified by the community during formative research (lack of time, negative outcome expectations, enjoyment, social support, see table below). Module options will be rotated and constantly updated to keep participants engaged.

Wait List Control Condition: Will receive the intervention after 12 weeks following baseline assessments.

Inclusion Criteria:

• 21 years or older
• Underactive (<60 min/week moderate PA)
• Able to speak/read English
• Willing to be assigned to either condition
• Access to a telephone
• Not planning to move from the area in the next 4 months
• Healthy (BMI 18.5-45; No history of heart disease, myocardial infarction, angina, stroke, or orthopedic conditions which limit mobility, or any serious medical condition that would make physical activity unsafe; no psychiatric hospitalization in past 3 years).