The effect of Bikram yoga on endothelial function in young and middle-aged and older adults.

The purpose of this investigation was to determine if Bikram yoga, a style of heated hatha yoga, would improve endothelial function in young and middle-aged and older, healthy adults. This trial was performed in 36 young (n = 17) and middle-aged and older adults (n = 19) who completed 3 weekly Bikram yoga classes for 8 weeks. Height, body weight and body composition were determined and endothelial function was measured noninvasively using brachial artery flow-mediated dilation (FMD) before and after the intervention. No changes in body weight, BMI or body fat percentage occurred as a result of the intervention in either group. Brachial artery FMD was significantly increased in middle-aged and older (P < 0.05) but not in young adults as a result of the intervention. The results demonstrate that a relatively short-term Bikram yoga practice might significantly improve vascular endothelial function in middle-aged and older adults. While apparently healthy individuals in this study experienced no adverse events, those with preexisting conditions should take caution and consult with a physician prior to engaging in this style of yoga.

Impact of Hot Yoga on Arterial Stiffness and Quality of Life in Normal and Overweight/Obese Adults.

BACKGROUND: Obesity is associated with arterial stiffening and diminished quality of life. Bikram yoga may be a feasible alternative to traditional exercise among obese individuals. Accordingly, the purpose of this study was to investigate the impact of Bikram yoga, a heated style of hatha yoga, on arterial stiffness in normal and overweight/obese adults. METHODS: Forty-three (23 normal body mass index or BMI; 20 overweight/obese) apparently healthy participants completed an 8-week Bikram yoga intervention. Body composition was estimated via dual energy x-ray absorptiometry, arterial stiffness was measured via brachialankle pulse wave velocity, and health-related quality of life was assessed via RAND 36-Item Short Form survey at baseline and at the end of the 8-week intervention. RESULTS: After the intervention, brachial-ankle pulse wave velocity decreased (P < .05) in overweight/obese participants while no such changes were observed in normal BMI participants. In the quality of life measures, emotional well-being improved (P < .05) in both groups, and general health improved (P < .05) only in the normal weight BMI group. CONCLUSION: Bikram yoga ameliorates arterial stiffness in overweight/obese adults and can positively impact quality of life regardless of BMI.

The effect of Bikram yoga on arterial stiffness in young and older adults.

BACKGROUND AND OBJECTIVE: Bikram yoga is the most popular form of hot yoga, despite the limited information available on its cardiovascular benefits. This study sought to determine the effect of Bikram yoga on arterial stiffness and insulin resistance in young and older adults. METHODS: Twenty-four young (mean age±standard deviation, 30±1 years) and 18 middle-aged and older (mean age, 53±2 years) adults completed an 8-week Bikram yoga intervention. Bikram yoga classes were performed for 90 minutes per session, three times per week, in a room heated to 40.5°C with 40%--60% relative humidity. RESULTS: Body mass, body fat percentage, blood pressure, and fasting blood glucose and triglyceride concentrations did not significantly change as a result of the intervention in either the young or the older group. Trunk flexibility, as measured by the sit-and-reach test, increased in both groups (p<0.01). Total (p<0.05) and low-density lipoprotein cholesterol (p<0.05) levels, plasma insulin concentrations (p<0.01), and scores on the homeostatic model of the assessment of insulin resistance (p<0.01) decreased in older adults, whereas total and high-density lipoprotein cholesterol concentrations were reduced in young adults (all p<0.05). Carotid artery compliance (p<0.05) was increased and ß-stiffness index decreased in young (p<0.05) but not in older adults. Carotid pulse pressure did not significantly change in either group. CONCLUSION: A relatively short-term Bikram yoga intervention improved arterial stiffness in young but not older adults and significantly reduced insulin resistance index in older but not young adults.

Hatha yoga and vascular function: results from cross-sectional and interventional studies.

The aim of this study was to determine the effect of hatha yoga on arterial elasticity and endothelial function. First, a cross-sectional study was performed to determine whether yoga practitioners would demonstrate greater arterial compliance and endothelium-dependent vasodilation than their sedentary peers. Second, an intervention study involving 13 sedentary middle-aged and older adults (51 ± 7 years) was performed to determine whether 12 weeks of hatha yoga would elicit increases in arterial compliance and endothelial function. In the cross-sectional study involving a total of 34 subjects, there were no group differences in body fatness, blood lipid and lipoprotein concentrations, carotid artery compliance or brachial artery flow-mediated dilation (FMD). Hemoglobin A1c was lower in yoga practitioners than in sedentary adults (P < 0.05). Total cholesterol and hemoglobin A1c decreased after the intervention (P < 0.05) while carotid artery compliance and brachial artery FMD did not change. The results of both cross-sectional and interventional studies indicate that regular practice of hatha yoga is not associated with improvements in vascular functions.

Muscle spasticity associated with reduced whole-leg perfusion in persons with spinal cord injury.

OBJECTIVE: To determine the association between peripheral blood flow and spasticity in individuals with spinal cord injury (SCI). DESIGN: A cross-sectional study with measurements of muscle spasticity and whole-limb blood flow in individuals with SCI. SETTING: University of Texas at Austin and Brain & Spine Recovery Center, Austin, TX, USA. PARTICIPANTS: Eighteen individuals (14 males and 4 females) with SCI were classified into high (N = 7), low (N = 6), and no (N = 5) spasticity groups according to the spasticity levels determined by the modified Ashworth scale scores. INTERVENTIONS: Whole-limb blood flow was measured in the femoral and brachial arteries using Doppler ultrasound and was normalized to lean limb mass obtained with dual-energy X-ray absorptiometry. OUTCOME MEASURES: Limb blood flow and muscle spasticity. RESULTS: Age, time post-SCI, and the American Spinal Injury Association impairment scale motor and sensory scores were not different among groups with different muscle spasticity. Femoral artery blood flow normalized to lean leg mass was different (P = 0.001) across the three spasticity groups (high 78.9 ± 16.7, low 98.3 ± 39.8, no 142.5 ± 24.3 ml/minute/kg). Total leg muscle spasticity scores were significantly and negatively correlated with femoral artery blood flow (r = -0.59, P < 0.01). There was no significant difference in brachial artery blood flow among the groups. CONCLUSIONS: Whole-leg blood flow was lower in individuals with greater spasticity scores. These results suggest that a reduction in lower-limb perfusion may play a role, at least in part, in the pathogenesis leading to muscle spasticity after SCI.