title: How sedentary and physically active are breast cancer survivors, and which population subgroups have higher or lower levels of these behaviors?
abstract: OBJECTIVE
  Physical activity (PA) and sedentary behavior may influence the physical and mental health of breast cancer survivors; however, few studies have objectively measured these behaviors in this population. We used accelerometers to measure the PA and sedentary time levels of breast cancer survivors and examined the demographic, behavioral, and medical correlates of these behaviors using two complementary approaches.
  
  
  METHODS
  A total of 259 breast cancer survivors wore an accelerometer for 7 days during waking hours and completed a questionnaire. We used linear regression and classification trees to investigate correlates of PA and sedentary time.
  
  
  RESULTS
  The breast cancer survivors in this study (mean age = 61 years, mean time since diagnosis = 3 years) were sedentary for a daily average of 8.2 h, in light-intensity PA for 5.8 h and in moderate-to-vigorous intensity PA (MVPA) for 32 min, with 16 % meeting PA guidelines. Participants with high comorbidity were the least likely to be meeting guidelines (0 %), while a subgroup of participants with no/low comorbidity, a university degree, and higher levels of pre-diagnosis MVPA were the most likely to be meeting guidelines (47 %). Older participants (70+ years) were the most likely to have sedentary time levels at least twice as high as activity levels, while participants who were younger than 70 years and not in the lowest category of pre-diagnosis MVPA were the least likely.
  
  
  CONCLUSIONS
  Interventions to facilitate physical activity and reduce sedentary time among breast cancer survivors should consider comorbidity status and previous PA experience.
authors.affiliation: Cancer Control Research, British Columbia Cancer Agency, 675 West 10th Avenue, Vancouver, BC, V5Z 1L3, Canada. tboyle@bccrc.ca.|School of Population and Public Health, The University of British Columbia, Vancouver, British Columbia, Canada. tboyle@bccrc.ca.|Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia. tboyle@bccrc.ca.
authors.forename: Terry
authors.initials: T
authors.lastname: Boyle
authors.affiliation: Faculty of Health Disciplines, Athabasca University, Athabasca, AB, Canada.
authors.forename: Jeff K
authors.initials: JK
authors.lastname: Vallance
authors.affiliation: Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia.
authors.forename: Emily K
authors.initials: EK
authors.lastname: Ransom
authors.affiliation: Cancer Epidemiology Centre, Cancer Council Victoria, Melbourne, Australia.|School of Population and Global Health, The University of Melbourne, Melbourne, Australia.|Physical Activity Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Australia.
authors.forename: Brigid M
authors.initials: BM
authors.lastname: Lynch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000503:physiopathology* / Q000523:psychology; D016022:Case-Control Studies; D015444:Exercise / Q000502:physiology; D005260:Female; D015438:Health Behavior; D006801:Humans; D008875:Middle Aged; D009043:Motor Activity; D057185:Sedentary Behavior; D011795:Surveys and Questionnaires; D017741:Survivors
keywords: Breast cancer; Cancer; Oncology; Physical activity; Sedentary behavior; Survivorship