Alberta Physical Activity and Breast Cancer Prevention (ALPHA) Trial
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Prevention
|Official Title:||Alberta Physical Activity and Breast Cancer Prevention (ALPHA) Trial|
- Changes in estrone, estradiol and adiposity levels [ Time Frame: Up to 12 months ]The effect of the exercise intervention on sex steroid and adiposity levels after one year is examined.
- Changes in mammographic density, insulin resistance and inflammatory markers [ Time Frame: Up to 12 months ]The effect of the exercise intervention after one year is examined.
- The effect of the exercise intervention on exercise adherence and quality of life. [ Time Frame: Up to 12 months ]
|Study Start Date:||June 2002|
|Study Completion Date:||July 2007|
|Primary Completion Date:||June 2006 (Final data collection date for primary outcome measure)|
Women randomized to the exercise intervention arm completed a one year aerobic exercise intervention of 225 minutes/week.
Behavioral: Aerobic exercise intervention
Women in the exercise arm underwent a year-long exercise intervention of five days per week of 45 minutes/session of moderate-vigorous intensity aerobic exercise.
No Intervention: Control
Women randomized to the control arm were asked to maintain their regular lifestyle which meant no changes to their exercise or dietary intake. Women eligible for this trial were inactive and hence were expected not to increase their levels of physical activity in the control arm.
The goal of this study is to examine how a one-year exercise intervention, as compared to a usual sedentary lifestyle, influences specific biologic mechanisms that are hypothesized to be operative in the association between physical activity and breast cancer risk. These biologic mechanisms include sex hormone concentrations (estrone, estradiol and sex-hormone binding globulin); measures of adiposity and obesity; mammographic density; insulin-like growth factors; and insulin resistance.
A two-centered, two-armed randomized controlled trial (RCT) of exercise and risk factors for breast cancer will be conducted. Approximately 334 postmenopausal, sedentary women will be recruited to the study. Participants will be randomized to one of two groups: an exercise intervention, or a control group. The intervention group will undertake five weekly exercise sessions of 60 minutes each; three will be facility-based and two will be home-based each week. The Edmonton and Calgary exercise oncology facilities will be working in collaboration, and each will include both the controls and exercise intervention arms of the trial. The exercise intervention will last for 12 months. The control group will be asked not to change their usual level of activity during that time.
Baseline assessments will be obtained of serum sex hormones (estrone and estradiol), measures of obesity and adiposity, mammographic density, serum insulin growth factor (IGF)-1, insulin resistance, aerobic capacity, and psychosocial health measures. At the end of the study, all baseline assessments will be repeated and compared between the two groups.
This study will specifically address identified gaps in knowledge, in terms of examining the simultaneous effect of physical activity on several biologic mechanisms in a controlled trial setting, building on evidence from the only other randomized controlled trial on this topic. Strengths of the proposal include the multi-centered setting (utilizing facilities in both Calgary and Edmonton), and the collaboration of an experienced multi-disciplinary research team from across North America.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00522262
|Alberta Cancer Board|
|Calgary, Alberta, Canada, T2N 4N2|
|University of Alberta|
|Edmonton, Alberta, Canada, T6G 2H9|
|Principal Investigator:||Christine M Friedenreich, PhD||Alberta Health Services|