title: Do older adults with higher daily ambulatory activity have lower central blood pressure?
abstract: OBJECTIVE
  We aimed to test the hypothesis that central blood pressure (BP) would be lower in healthy older adults with greater daily ambulatory activity.
  
  
  METHODS
  Forty-three (24 women, 19 men) older adults wore a triaxial accelerometer at the hip for 1 week. The volume of ambulatory activity was estimated by average steps per day. As a proxy of intensity of ambulatory activity, 1-min peak step accumulation, or the maximum number of steps taken within a minute was averaged from each day. Participants were considered "active" if they had >7500 steps per day or >105 steps per min. Radial arterial tonometry was used to estimate central (aortic) BP from pulse wave analysis.
  
  
  RESULTS
  After adjusting for age and sex, adults with higher steps per day (n = 18) tended to have lower central pulse pressure (p = 0.08). Interestingly, adults with higher peak step accumulation (n = 25) had significantly lower central pulse pressure (40.4 ± 1.6 vs. 46.8 ± 2.0 mmHg; p = 0.02) after adjusting for age and sex. Stepwise regression including age, sex, body mass index, and peak step accumulation found body mass index to be the strongest predictor of central systolic BP [β = 0.42, 95 % CI (0.13, 0.70), p = 0.004] while peak step accumulation was the strongest predictor of central pulse pressure [β = -0.31, 95 % CI (-0.01, -0.60), p = 0.043].
  
  
  CONCLUSIONS
  These results find older adults with an "active" daily walking pattern, particularly having a higher number of maximal steps in a minute, have lower central pulse pressure than older adults with lower daily ambulatory activity.
authors.affiliation: Department of Health, Exercise and Sport Sciences, Texas Tech University, Box 43011, Lubbock, TX, 7409-3011, USA. joaquin.gonzales@ttu.edu.
authors.forename: Joaquin U
authors.initials: JU
authors.lastname: Gonzales
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D063177:Pulse Wave Analysis; D016138:Walking / Q000502:physiology*
keywords: Accelerometer; Aging; Blood pressure; Central blood pressure; Physical activity; Pulse wave analysis; Walking