Document Detail

Biobehavioral Factors Mediate Exercise Effects on Fatigue in Breast Cancer Survivors.
MedLine Citation:
PMID:  24212124     Owner:  NLM     Status:  Publisher    
PURPOSE: Examine mediators of fatigue response to an exercise intervention for breast cancer survivors (BCS) in a pilot randomized controlled trial.
METHODS: Postmenopausal BCS (n=46; ≤ Stage II), off primary treatment, and reporting fatigue and/or sleep dysfunction were randomized to a 3-month exercise intervention (160 minutes/week of moderate intensity aerobic walking, twice weekly resistance training with resistance bands) or control group. Six discussion group sessions provided behavioral support to improve adherence. Fatigue, serum cytokines, accelerometer physical activity, cardiorespiratory fitness, sleep dysfunction, and psychosocial factors were assessed at baseline and 3 months.
RESULTS: Exercise intervention effect sizes for fatigue were: fatigue intensity d=0.30 (p=.34), interference d=-0.38 (p=.22), and general fatigue d=-0.49 (p=.13). Using Freedman-Schatzkin difference-in-coefficients tests, increase in fatigue intensity was significantly mediated by interleukin (IL)-6 (82%), IL-10 (94%), IL-6:IL-10 (49%), and tumor necrosis factor (TNF)-alpha:IL-10 (78%) with reduced sleep dysfunction increasing the relationship between intervention and fatigue intensity rather than mediating intervention effects (-88%). Decrease in fatigue interference was mediated by sleep dysfunction (35%) while IL-10 and pro:anti-inflammatory cytokine ratios increased the relationship between intervention and interference (-25% to -40%). The reduction in general fatigue was significantly mediated by minutes of physical activity (76%), sleep dysfunction (45%), and physical activity enjoyment (40%) with IL-10 (-40%) and IL-6:IL-10 (-11%) increasing the intervention-fatigue relationship. In the intervention group, higher baseline fatigue, anxiety, depression, and perceived exercise barriers interference predicted a greater decline in fatigue interference and/or general fatigue during the intervention.
CONCLUSIONS: Biobehavioral factors mediated and enhanced intervention effects on fatigue while psychosocial factors predicted fatigue response. Further study is warranted to confirm our results and improve understanding of relationships that mediate and strengthen the intervention-fatigue association.
Laura Q Rogers; Sandra Vicari; Rita Trammell; Patricia Hopkins-Price; Amanda Fogleman; Allison Spenner; Krishna Rao; Kerry S Courneya; Karen S Hoelzer; Randall Robbs; Steven Verhulst
Related Documents :
560004 - Lak of influence of glucagon on glucose homeostasis after prolonged exercise in rats.
2843314 - Effects of opioid antagonism on the haemodynamic and hormonal responses to exercise.
3905394 - Plasma vasopressin, renin activity, and aldosterone responses to maximal exercise in ac...
23145504 - Singing classes for chronic obstructive pulmonary disease: a randomized controlled trial.
21178374 - Aetiology and prevention of injuries in elite young athletes.
22126974 - Physical responses of different small-sided game formats in elite youth soccer players.
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2013-11-7
Journal Detail:
Title:  Medicine and science in sports and exercise     Volume:  -     ISSN:  1530-0315     ISO Abbreviation:  Med Sci Sports Exerc     Publication Date:  2013 Nov 
Date Detail:
Created Date:  2013-11-11     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8005433     Medline TA:  Med Sci Sports Exerc     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
1University of Alabama at Birmingham, Birmingham, AL; 2SIU School of Medicine, Springfield, IL; 3University of Alberta, Edmonton, Alberta, Candada; 4Springfield Clinic, Springfield, IL.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Social Support for Parents of Deaf Children: Moving Toward Contextualized Understanding.
Next Document:  Synthesis, ex vivo and in silico studies of 3-cyano-2-pyridone derivatives with vasorelaxant activit...