Background: Dysregulation of adipokines, such as adiponectin and leptin, is associated with a variety of chronic diseases, including cancer. Physical activity protects against breast cancer and one of the mechanisms which may underlie this association is exercise-induced changes in adipokine levels. The WISER Sister Trial was a three-armed randomized controlled trial in premenopausal women (n = 137) with an elevated risk for breast cancer.
Methods: A 5-menstrual-cycle-long dosed aerobic exercise intervention compared low-dose exercise (150 min/wk; n = 44) or high-dose exercise (300 min/wk; n = 48) with a control group asked to maintain usual activity levels (n = 45). Exercise intensity progressed to and was maintained at 70% to 80% of age predicted heart rate max. Body composition and adipokine levels were measured at baseline and follow-up.
Results: We observed significant linear trends for increased fitness capacity (Δ%: −2.0% control, 10.1% low dose, 13.1% high dose), decreased fat tissue-to-total tissue mass (Δ%: 0.7% control, −2.9% low dose, −3.7% high dose), increased body fat adjusted adiponectin (Δ%: −0.6% control, 0.6% low dose, 0.9% high dose), and decreased body fat adjusted leptin (Δ%: 0.7% control, −8.2% low dose, −10.2% high dose).
Conclusions: In this randomized clinical trial of premenopausal women at risk for breast cancer, we demonstrate a dose–response effect of exercise on adiponectin and leptin and that dose response is dependent on changes in body fat.
Impact: Improved adipokine levels, achieved by aerobic exercise training-induced decreases in body fat, may decrease breast cancer risk for high-risk premenopausal women. Cancer Epidemiol Biomarkers Prev; 25(8); 1195–200. ©2016 AACR.
This article is featured in Highlights of This Issue, p. 1193
- Received October 13, 2015.
- Revision received March 16, 2016.
- Accepted April 3, 2016.
- ©2016 American Association for Cancer Research.