title: The influence of physical activity and yoga on central arterial stiffness.
abstract: OBJECTIVE
  Central arterial stiffness is an accepted risk factor for cardiovascular disease. While aerobic activity is associated with reduced stiffness the influence of practicing yoga is unknown. The aims of this study were to: 1) evaluate arterial stiffness in middle-aged adults who regularly practiced yoga, performed regular exercise, or were inactive, 2) evaluate the reproducibility of arterial stiffness measured in the left and right carotid artery and by pulse wave velocity (PWV).
  
  
  METHODS
  Twenty six healthy subjects (male and female, 40-65 yrs old) were tested on two separate days. Carotid artery distensibility (DC) was measured with ultrasound. Physical activity was determined by questionnaire.
  
  
  RESULTS
  Yoga and aerobic subjects had similar physical activity levels. Yoga and aerobic groups were not different in either DC (p = 0.26) or PWV (p = 0.21). The sedentary group had lower DC and higher PWV compared to the aerobic and yoga groups (both, p < 0.001). Stiffness measures were reliable day to day (coefficients of variation approximately 2.5%) and similar between left and right arteries (CV = 2.2%).
  
  
  CONCLUSIONS
  Physical activity was a strong predictor of both measures of arterial stiffness, although other factors such as nutritional status need to be accounted for. An independent effect of practicing yoga could not be detected. Stiffness measures were reproducible and left and right sides were consistent with each other.
authors.affiliation: Department of Kinesiology, University of Georgia, 115 Ramsey Center, Athens, GA 30602, USA. courtney_duren@yahoo.com
authors.forename: Courtney M
authors.initials: CM
authors.lastname: Duren
authors.forename: Marie E
authors.initials: ME
authors.lastname: Cress
authors.forename: Kevin K
authors.initials: KK
authors.lastname: McCully