Impact of Length of Exercise Intervention on Peak Oxygen Consumption in Women with Breast Cancer: A Meta-Analysis

Wednesday, 9 July 2008
Chun-Ja Kim, RN, PhD , Department of Nursing, Ajou University College of Nursing, Suwon, South Korea
Duck-Hee Kang, RN, PhD, FAAN , School of Nursing, The University of Alabama at Birmingham, Birmingham, AL
Jee Won Park, RN, PhD , Dept. of Nursing, Ajou University College of Nursing, Suwon, South Korea

Learning Objective 1: determine the overall effect of exercise intervention focusing on cardiopulmonary function as assessed by VO2 peak.

Learning Objective 2: determine the difference of cardiopulmonary function associate with length of exercise intervention (less than 12-week intervention versus more than 12-week intervention).

It is generally recommended that exercise intervention should last longer than 12 weeks in order to get beneficial effect on cardiopulmonary function. However, the reported length of exercise intervention has been varied from 6 weeks to 26 weeks, largely from small sample sizes. The purpose of this meta-analysis is determined not only the overall effect, but also difference of aerobic exercise (less than 12-week intervention versus more than 12-week intervention) on cardiopulmonary function as assessed by peak oxygen consumption (VO2 peak). From the search of the MEDLINE, CINAHL and PubMed (1985 to June 2007), we included only randomized controlled trials of aerobic exercise in women with breast cancer. Five trials involving 280 women met the inclusion criteria. The Comprehensive Meta Analysis [CMA]/WIN 2.0 was used to calculate effect size, weighted mean differences [WMD], 95% confidence interval [CI], Q statistics for the test of heterogeneity, and funnel plots for publication bias. The SPSS/WIN 12.0 was used to characterize the sample and variables of the study for descriptive statistics. Findings indicate that aerobic exercise significant improves VO2 peak absolute (L/min), weighted mean difference [WMD] 0.705, 95% confidence interval [CI] 0.140 -1.270 (WMD 0.666 vs. 0.742) and VO2 peak relative (ml/kg/min) WMD 0.410, 95% CI 0.120 - 0.701. Future studies need to focus on the long-term adherence and benefits of more than 12-week aerobic exercise on cardiopulmonary function in women with breast cancer using a rigorous research design and larger sample sizes.