title: Type 2 diabetes exaggerates exercise effort and impairs exercise performance in older women.
abstract: OBJECTIVE
  Type 2 diabetes mellitus (T2DM) is associated with high levels of disability and mortality. Regular exercise prevents premature disability and mortality, but people with T2DM are generally sedentary for reasons that are not fully established. We previously observed that premenopausal women with T2DM report greater effort during exercise than their counterparts without diabetes, as measured by the Rating of Perceived Exertion (RPE) scale. We hypothesized that RPE is greater in older women with T2DM versus no T2DM.
  
  
  METHODS
  We enrolled overweight, sedentary women aged 50-75 years with (n=26) or without T2DM (n=28). Participants performed submaximal cycle ergometer exercise at 30 W and 35% of individually-measured peak oxygen consumption (35% VO2peak). We assessed exercise effort by RPE (self-report) and plasma lactate concentration.
  
  
  RESULTS
  VO2peak was lower in T2DM versus controls (p=0.003). RPE was not significantly greater in T2DM versus controls (30 W: Control, 10.4±3.2, T2DM, 11.7±2.3, p=0.08; 35% VO2peak: Control, 11.1±0.5, T2DM, 12.1±0.5, p=0.21). However, lactate was greater in T2DM versus controls (p=0.004 at 30 W; p<0.05 at 35% VO2peak). Greater RPE was associated with higher lactate, higher heart rate, and a hypertension diagnosis (p<0.05 at 30 W and 35% VO2peak).
  
  
  CONCLUSIONS
  Taken together, physiological measures of exercise effort were greater in older women with T2DM than controls. Exercise effort is a modifiable and thereby targetable end point. In order to facilitate regular exercise, methods to reduce exercise effort in T2DM should be sought.
  
  
  BACKGROUND
  NCT00785005.
authors.affiliation: Department of Medicine; Division of General Internal Medicine , University of Colorado (CU) School of Medicine (SOM) , Aurora, Colorado , USA ; Center for Women's Health Research , Aurora, Colorado , USA.
authors.forename: A G
authors.initials: AG
authors.lastname: Huebschmann
authors.affiliation: Center for Women's Health Research , Aurora, Colorado , USA ; Division of Geriatrics, Aurora, Colorado , USA.
authors.forename: W M
authors.initials: WM
authors.lastname: Kohrt
authors.affiliation: Department of Medicine; Division of General Internal Medicine , University of Colorado (CU) School of Medicine (SOM) , Aurora, Colorado , USA ; Center for Women's Health Research , Aurora, Colorado , USA.
authors.forename: L
authors.initials: L
authors.lastname: Herlache
authors.affiliation: CU-SOM Department of Biostatistics, Aurora, Colorado , USA.
authors.forename: P
authors.initials: P
authors.lastname: Wolfe
authors.affiliation: Center for Women's Health Research , Aurora, Colorado , USA ; Division of Cardiology, Aurora, Colorado , USA.
authors.forename: S
authors.initials: S
authors.lastname: Daugherty
authors.affiliation: Center for Women's Health Research , Aurora, Colorado , USA ; Division of Endocrinology, Aurora, Colorado , USA.
authors.forename: J Eb
authors.initials: JE
authors.lastname: Reusch
authors.affiliation: Department of Medicine; Division of General Internal Medicine , University of Colorado (CU) School of Medicine (SOM) , Aurora, Colorado , USA.
authors.forename: T A
authors.initials: TA
authors.lastname: Bauer
authors.affiliation: Department of Medicine; Division of General Internal Medicine , University of Colorado (CU) School of Medicine (SOM) , Aurora, Colorado , USA ; Center for Women's Health Research , Aurora, Colorado , USA ; Division of Cardiology, Aurora, Colorado , USA.
authors.forename: J G
authors.initials: JG
authors.lastname: Regensteiner
keywords: Behavior Research; Exercise Habits; Physical Activity Epidemiology; Type 2 Diabetes