Environment and Breast Cancer: Science Review

Evidence From Humans
Print this page
Effects of a moderate intensity exercise intervention on estrogen metabolism in postmenopausal women
Atkinson, C., Lampe, J. W., Tworoger, S. S., Ulrich, C. M., Bowen, D., Irwin, M. L., Schwartz, R. S., Rajan, B. K., Yasui, Y., Potter, J. D., McTiernan, A. Cancer Epidemiology, Biomarkers & Prevention. 2004. 13:5, 868-74.
Topic area
Body size - Physical Activity
Study design
Other: Clinical trial
Study Participants
Menopausal Status
The menopausal status of women included in this study is listed here.
Post menopausal
Number in Cohort
Cohort: 168
Cohort participation rate
Retention/participation exceeded 70% for exposed a
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
In: women age 55-75 at baseline, sedentary women, lived in the Seattle, Washington area, and with a BMI of 25 or greater Ex: women who used: hormone therapy, herbal hormones, tamoxifen, raloxifen or oral contraceptives within 6 months of study; medical conditions that inhibit moderate to intense exercise; clinically diagnosed with diabetes; used tobacco shortly before study; consumed more than two alcoholic drinks a day shortly before study
Comment about participation selection
Strengths: anthropometric data was measured, one of the first studies to investigate the effects of a 12 month exercise program on the urinary excretion of 2-OH E1, 16 alpha-OH E1 and their ratio in a previously sedentary and overweight population of postmenopausal women, excellent adherence to the exercise program, and had a low drop out rate Limitation: small sample size
Exposures investigated
Height, weight and BMI
How exposure was measured
Questionnaire, self-administered Anthropometric measurement, researcher-administered
Ethnic groups with separate analysis
If this study provided a separate analysis by ethnic or racial group, the groups are listed here.
Confounders considered
Other breast cancer risk factors, such as family history, age at first birth, and hormone replacement therapy use, that were taken into account in the study.
Adequately controlled
Genetic characterization included
If the study analyzed relationships between environmental factors and inherited genetic variations, this field will be marked “Yes.” “No”, if not.
Results Comments
Overall there were no significant effects of the exercise intervention on 2-hydroxyestrone, 16-alpha-hydroxyestrone, or their ratio.
Author address
Cancer Prevention Program, Fred Hutchinson Cancer Research Center, P. O. Box 19024, Seattle, WA 98109, USA.