title: Randomized controlled trial of weight training and lymphedema in breast cancer survivors.
abstract: OBJECTIVE
  Lymphedema is a common condition that breast cancer survivors face. Despite a lack of supporting evidence from prospective observational studies, occupational and leisure time physical activity are feared to be possible risk factors for lymphedema onset or exacerbation. We examined effects of supervised upper- and lower-body weight training on the incidence and symptoms of lymphedema in 45 breast cancer survivors who participated in the Weight Training for Breast Cancer Survivors study.
  
  
  METHODS
  Participants were on average 52 years old, 4 to 36 months post-treatment, and had axillary dissection as part of their treatment. Thirteen women had prevalent lymphedema at baseline. The intervention was twice-a-week weight training over a period of 6 months. Lymphedema was monitored at baseline and 6 months by measuring the circumference of each arm, and by self-report of symptoms and clinical diagnosis.
  
  
  RESULTS
  None of the intervention-group participants experienced a change in arm circumferences > or = 2.0 cm after a 6-month exercise intervention. Self-reported incidence of a clinical diagnosis of lymphedema or symptom changes over 6 months did not vary by intervention status (P = .40 and P = .22, respectively).
  
  
  CONCLUSIONS
  This is the largest randomized controlled trial to examine associations between exercise and lymphedema in breast cancer survivors. The results of this study support the hypotheses that a 6-month intervention of resistance exercise did not increase the risk for or exacerbate symptoms of lymphedema. These results herald the need to start reevaluating common clinical guidelines that breast cancer survivors avoid upper body resistance activity for fear of increasing risk of lymphedema.
authors.affiliation: Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Rehana L
authors.initials: RL
authors.lastname: Ahmed
authors.forename: William
authors.initials: W
authors.lastname: Thomas
authors.forename: Douglas
authors.initials: D
authors.lastname: Yee
authors.forename: Kathryn H
authors.initials: KH
authors.lastname: Schmitz
mesh_terms: D001943:Breast Neoplasms / Q000601:surgery*; D003131:Combined Modality Therapy; D015444:Exercise; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008209:Lymphedema / Q000209:etiology*; D008875:Middle Aged; D012306:Risk; D017741:Survivors; D014891:Weight Lifting