Nantinee Nualnim

Effects of Swimming Training on Blood Pressure and Vascular Function in Adults >50 Years of Age

Swimming is ideal for older adults because it includes minimum weight-bearing stress and decreased heat load. However, there is very little information available concerning the effects of regular swimming exercise on vascular risks. We determined if regular swimming exercise would decrease arterial blood pressure (BP) and improve vascular function. Forty-three otherwise healthy adults >50 years old (60 ± 2) with prehypertension or stage 1 hypertension and not on any medication were randomly assigned to 12 weeks of swimming exercise or attention time controls. Before the intervention period there were no significant differences in any of the variables between groups. Body mass, adiposity, and plasma concentrations of glucose and cholesterol did not change in either group throughout the intervention period. Casual systolic BP decreased significantly from 131 ± 3 to 122 ± 4 mm Hg in the swimming training group. Significant decreases in systolic BP were also observed in ambulatory (daytime) and central (carotid) BP measurements. Swimming exercise produced a 21% increase in carotid artery compliance (p <0.05). Flow-mediated dilation and cardiovagal baroreflex sensitivity improved after the swim training program (p <0.05). There were no significant changes in any measurements in the control group that performed gentle relaxation exercises. In conclusion, swimming exercise elicits hypotensive effects and improvements in vascular function in previously sedentary older adults.

Comparison of Central Artery Elasticity in Swimmers, Runners, and the Sedentary

Although swimming is one of the most popular, most practiced, and most recommended forms of physical activity, little information is available regarding the influence of regular swimming on vascular disease risks. Using a cross-sectional study design, key measurements of vascular function were performed in middle-aged and older swimmers, runners, and sedentary controls. There were no group differences in age, height, dietary intake, and fasting plasma concentrations of glucose, total cholesterol, and low-density lipoprotein cholesterol. Runners and swimmers were not different in their weekly training volume. Brachial systolic blood pressure and pulse pressure were higher (p <0.05) in swimmers than in sedentary controls and runners. Runners and swimmers had lower (p <0.05) carotid systolic blood pressure and carotid pulse pressure than sedentary controls. Carotid arterial compliance was higher (p <0.05) and β-stiffness index was lower (p <0.05) in runners and swimmers than in sedentary controls. There were no significant group differences between runners and swimmers. Cardiovagal baroreflex sensitivity was greater (p <0.05) in runners than in sedentary controls and swimmers and baroreflex sensitivity tended to be higher in swimmers than in sedentary controls (p = 0.07). Brachial artery flow-mediated dilation was significant greater (p <0.05) in runners compared with sedentary controls and swimmers. In conclusion, our present findings are consistent with the notion that habitual swimming exercise may be an effective endurance exercise for preventing loss in central arterial compliance.

Central artery stiffness, neuropsychological function, and cerebral perfusion in sedentary and endurance-trained middle-aged adults.

Background: Midlife vascular disease risk is a strong risk factor for late-life dementia. Central arterial stiffness, a hallmark of vascular aging, is associated with accelerated brain aging and cognitive decline. Habitual aerobic exercise is an effective lifestyle strategy to reduce central arterial stiffness and is related to lower risk of cognitive impairment. Objective: To determine the associations among cardiopulmonary fitness, neuropsychological function, central arterial stiffness, and cerebral perfusion in the sedentary and endurance-trained middle-aged adults. Methods: Twenty-six sedentary and 32 endurance-trained middle-aged adults were measured for maximal oxygen consumption, central arterial stiffness determined by aortic pulse wave velocity and carotid ultrasound, neuropsychological function, and regional cerebral blood flow assessed by MRI. Results: There were no group differences in age, sex, ethnicity, education, blood pressure, and carotid intima–media wall thickness (all P > 0.05). Neuropsychological performance and occipitoparietal perfusion were greater, and central arterial stiffness was lower in endurance-trained individuals than in sedentary individuals (all P < 0.05). Greater cardiopulmonary fitness was related to better cognitive composite scores, including memory and attention-executive function (r = 0.28–0.40, P < 0.05). Lower carotid arterial stiffness was associated with better neuropsychological outcome independent of age, sex, and education (r = −0.32 to −0.35, P < 0.05), and correlated with greater occipitoparietal blood flow (r = −0.37 to −0.51, P < 0.05). Conclusion: Lower carotid artery stiffness in endurance-trained adults is associated with better neuropsychological outcome and greater occipitoparietal perfusion.

Arterial Stiffening, Wave Reflection, and Inflammation in Habitually Exercising Systemic Lupus Erythematosus Patients

BACKGROUND Chronic systemic inflammation has been implicated in the pathogenesis of hypertension and cardiovascular disease. Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by chronic inflammation and an increased risk for cardiovascular disease. Currently few studies have evaluated the potential cardiovascular benefits of exercise in SLE. It is unknown whether the favorable effect of habitual exercise on arterial stiffness observed in healthy adults can be extended to SLE. Therefore, as an initial step, we determined the association between habitual exercise, inflammatory markers, central arterial compliance, and aortic wave reflection in healthy adults and SLE patients. METHODS We studied 41 adults, aged 33 ± 11 years (15 healthy controls, 12 sedentary SLE, and 14 physically active SLE patients). RESULTS Age, body mass index, and metabolic risk factors were not different between the three groups. Carotid arterial compliance was lower whereas augmentation index (AI) and inflammatory markers (C-reactive protein (CRP), interleukin (IL)-12, tumor necrosis factor-α (TNF-α)) were higher in sedentary SLE patients compared with healthy controls, but were not different between physically active SLE patients and healthy controls. Cardiac ejection fraction was lower in sedentary SLE than physically active SLE or healthy controls. In the pooled population, carotid arterial compliance was inversely associated with TNF-α (r = -0.38; P < 0.01), and AI was positively associated with both CRP (r = 0.33; P < 0.05) and intercellular adhesion molecule-1 (r = 0.28; P < 0.05). CONCLUSIONS SLE-associated stiffening of the central artery and wave reflection were not observed in habitually exercising adults with SLE. Furthermore, greater arterial stiffness was associated with higher inflammatory markers, suggesting that need for studies on inflammation and SLE-associated arterial stiffening.

Cerebral/Peripheral Vascular Reactivity and Neurocognition in Middle-Age Athletes

INTRODUCTION Midlife vascular disease risk is associated with higher incidence of cognitive impairment in late life. Regular aerobic exercise improves vascular function, which in turn may translate into better cognitive function. The purpose of this study was to determine the associations among cardiorespiratory fitness, cerebral and peripheral vascular reactivity, and cognitive function in sedentary and endurance-trained middle-age adults. METHODS Thirty-two endurance-trained and 27 healthy sedentary participants ages 43-65 yr underwent measurements of maximal oxygen uptake (VO2max), neurocognitive assessment, cerebrovascular reactivity to CO2 (CVR), and brachial artery flow-mediated dilation (FMD). RESULTS There were no group differences in age, sex, education level, fasting blood glucose, and blood pressure. Compared with sedentary subjects, endurance-trained athletes demonstrated better cognitive performance on memory (z-score: -0.36 ± 1.11 vs 0.30 ± 0.76, P < 0.01), attention-executive function (z-score: -0.21 ± 0.53 vs 0.18 ± 0.72, P = 0.02), and total cognitive composite scores (z-score: -0.27 ± 0.63 vs 0.23 ± 0.57, P < 0.01). Furthermore, brachial FMD (4.70% ± 2.50% vs 7.13% ± 3.09%, P < 0.01) and CVR (4.19% ± 0.71%·mm Hg⁻¹ vs 4.69% ± 1.06%·mm Hg⁻¹, P = 0.052) were greater in endurance-trained individuals than in the sedentary subjects. Total cognitive composite scores showed a significant positive association with brachial FMD (r = 0.36, P < 0.01) and CVR (r = 0.30, P = 0.03). Finally, when brachial FMD and CVR were entered as covariates, fitness-related group differences in total cognitive composite score were significantly attenuated (all P > 0.05). CONCLUSION Endurance-trained middle-age adults demonstrated better cognitive performance, which may, at least in part, be mediated by their enhanced vascular function, including cerebral and endothelial-dependent vascular reactivity.

Macro- and microvascular function in habitually exercising systemic lupus erythematosus patients.

Objectives: Vascular dysfunction is commonly observed in systemic lupus erythematosus (SLE) patients and may explain the accelerated cardiovascular disease (CVD) risk. It is unknown whether physical activity influences vascular function in SLE patients. We aimed to determine whether habitually exercising SLE patients also demonstrate a reduction in vascular function. Method: This study involved 41 young and middle-aged adults, including 15 healthy controls, 12 sedentary SLE patients, and 14 physically active SLE patients. Results: Flow-mediated dilation (FMD), a measure of macrovascular function, was lower (3.6 ± 1.3 vs. 8.1 ± 1.2%; p < 0.05) and inflammatory markers [C-reactive protein (CRP), interleukin (IL)-12, and tumour necrosis factor (TNF)-α] were higher in sedentary SLE patients than in age-matched healthy controls (p < 0.05). Importantly, FMD and inflammatory markers were not different between physically active SLE patients and healthy controls. There were no group differences in skin reactive hyperaemia (RH) or minimal vascular resistance, both measures of microvascular function. Physically active SLE patients had lower intercellular adhesion molecule (ICAM)-1 concentrations and SLE disease activity scores than their sedentary peers. FMD was inversely associated with IL-6 and IL-10 (both p < 0.05). Conclusions: Significant SLE-associated macrovascular dysfunction was absent in physically active SLE patients. Additionally, vascular function was associated with inflammatory markers, suggesting that the favourable influence of physical activity may be mediated by its effect on inflammation.

Aerobic fitness and cognitive function in midlife: an association mediated by plasma insulin

Insulin resistance in midlife increases the risk of dementia in late-life. In contrast, habitual aerobic exercise is an established strategy to ameliorate insulin resistance which may translate into better cognitive outcome. To determine the role of plasma insulin in mediating the relation between cardiorespiratory fitness and cognitive function, fifty-eight adults completed assessments of plasma insulin levels, maximal oxygen consumption (VO2max), and neuropsychological test performance. Endurance-trained subjects demonstrated better cognitive outcome (total composite z-score: 0.21 ± 0.08 versus −0.26 ± 0.10, P = 0.001) and lower concentrations of plasma insulin (12.6 ± 0.6 versus 21.3 ± 1.5 ulU/mL, P < 0.001) than sedentary subjects. Greater VO2max was significantly associated with higher memory performance (β = 0.37, P = 0.01) and lower plasma insulin levels (β = −0.68, P < 0.001). The significant association between VO2max and memory performance was abolished when the indirect effect of plasma insulin was statistically removed (β = 0.24, P = 0.19). Fitness-related cognitive enhancement may be mediated, at least in part, by plasma insulin levels.

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.