Effects of Aerobic Exercise Training on Peak Aerobic Capacity, Fatigue, and Psychological Factors During Radiation for Breast Cancer

Rehabilitation Oncology, 2005 by Drouin, Jacqueline S, Armstrong, Holly, Krause, Shawn, Orr, Jennifer, Et al

Radiation Treatment

Each participant was treated with external beam radiation on 5 days per week for 7 weeks. The affected breast and regional lymph nodes received a 4500 to 5000 cGy dose in 200 cGy fractions with a boost of 1000-1600 cGy delivered to the primary tumor bed. Treatment dosages were similar between groups.

STATISTICAL ANALYSIS

Analyses of the data were performed using the Statistical Package for the Social Sciences software program (SPSS/PC release 10.0.5, SPSS, Chicago 111). Originally, this study was designed as a multivariate analysis, however, since final data did not meet parametric assumptions, the Wilcoxon Sign-Rank Test (WSRT) was used to determine differences between baseline and final scores, the Wilcoxon-Mann-Whitney U (W-MWU) was used to assess differences between groups, and the Spearman Rank Correlation Coefficient was used to examine correlations between changes in peak VO^sub 2^ and the final subscales scores for mood and fatigue.21 Statistical significance for all tests was set at a probability level of P ≤ .05.

RESULTS

Thirty-nine women were referred by oncologists to take part in this study and of these 23 women met the inclusion criteria and agreed to participate. Twenty-one women completed the study; two participants in the PS group did not return for final testing due to personal time constraints. Data from one subject in the PS group also was eliminated from the final analysis, due to marked irregularities in her pre- and posttest physical measures from moderate to severe fluid retention during the initial test session. Participant demographics are presented in Table 1. Mann-Whitney U analysis revealed no significant differences between groups on all measures prior to testing. Participants in the AE group averaged 3.6 days per week of aerobic exercise over an 8-week period, while PS subjects averaged 3.9 days per week of participation during this same time period.

Peak Aerobic Capacity

Following the intervention, peak VO^sub 2^ measures in the AE group increased significantly (P

Mood Assessment

Analysis of the POMS data revealed significant improvements in the AE group following training on subscale factors of depression-dejection (P = .002) and anger-hostility (P = .013), but not for tension-anxiety (P = .142), vigor-activity (P = .325), fatigue-inertia (P = .242), or confusion-bewilderment (P = .377). In the PS group, there were no significant changes for subscale factors of tension-anxiety (P = .200), depression-dejection (P = .343), anger hostility (P = .173), vigor-activity (P = .198), or fatigue-inertia (P = .146). Interestingly, PS group values for confusion-bewilderment improved significantly (P = .026) following the intervention. Improvements in the mood factors are characterized by achieving a more negative number, and the values for mood are presented in Table 3.

Fatigue Assessment

Analysis of the data from the R-PFS revealed a significant improvement in the AE group for affective meaning (P = .019), while no significant changes were found for behavioral/severity (P = .362), cognitive/mood (P = .228), or the sensory subscale factor (P = .484). In the PS group, the sensory subscale factor for fatigue significantly worsened (P = .023), while the cognitive mood subscale significantly improved (P = .023). Changes in behavioral/severity (P = .232) and affective meaning were not statistically significant. The R-PFS values, like the POMS values, improve as the number decreases or becomes more negative. The results of the R-PFS factors are presented in Table 4.