Effects of heated water-based versus land-based exercise training on vascular function in individuals with peripheral artery disease

Peripheral artery disease (PAD) is an atherosclerotic disease that is associated with poor vascular function, walking impairment, and reduced quality of life. Land-based exercise therapy (LBET) is frequently recommended to improve walking and reduce symptoms. Recently, evidence has suggested that heated-water exercise therapy (HWET) is an effective intervention for PAD. However, the efficacy of LBET versus HWET in PAD patients had not been elucidated. Therefore, we sought to compare effects of LBET with HWET on cardiovascular function, exercise tolerance, physical function, and body composition in PAD patients. PAD patients (n = 53) were recruited and randomly assigned to a LBET group (n = 25) or HWET group (n = 28). The LBET group performed treadmill walking, whereas the HWET group performed walking in heated water for 12 wk. Leg (legPWV) and brachial-to-ankle arterial stiffness (baPWV), blood pressure (BP), ankle-brachial index (ABI), 6-min walking distance (6MWD), claudication onset time (COT), physical function, and body composition were assessed before and after 12 wk. There were significant group-by-time interactions (P \u3c 0.05) for legPWV, BP, 6MWD, COT, body composition, and resting metabolic rate (RMR). Both groups significantly reduced (P \u3c 0.05) legPWV, BP, and body fat percentage, and HWET measures were significantly lower than LBET measures. Both groups significantly increased 6MWD, COT, and RMR, and HWET group measures were significantly greater than LBET measures. A time effect was noted for baPWV reduction in both groups (P \u3c 0.05). These results suggest that both LBET and HWET improve cardiovascular function, exercise tolerance, and body composition, and HWET showed considerably greater improvements compared with LBET in patients with PAD

The Effects of Mat Pilates Training on Vascular Function and Body Fatness in Obese Young Women With Elevated Blood Pressure

BACKGROUND Effective nonpharmacological interventions targeting the enhancement of vascular function and decline of body fatness (BF) in obese individuals are indispensable for the prevention of hypertension and cardiovascular events in young adults. Mat Pilates training (MPT) has gained significant popularity worldwide, yet its effects on vascular function and body composition are understudied. We examined the effects of MPT on vascular function and BF in young obese women with elevated blood pressure (BP). METHODS Twenty-eight young obese women with elevated BP were randomized to an MPT (n = 14) or a nonexercising control (CON, n = 14) group for 12 weeks. Systemic arterial stiffness (brachial-ankle pulse wave velocity (baPWV)), brachial and aortic BP, wave reflection (augmentation index (AIx)), plasma nitric oxide (NO) levels, and BF percentage (BF%) were assessed before and after 12 weeks. RESULTS MPT significantly reduced (P ˂ 0.05) baPWV (−0.7 ± 0.2 m/s), AIx (−4 ± 1%), brachial systolic BP (−5 ± 1 mm Hg), aortic systolic BP (−6 ± 1 mm Hg), and BF% (−2 ± 1%), while significantly increasing plasma NO (6 ± 2 µM) (P ˂ 0.05) compared with CON. MPT improved systemic arterial stiffness, aortic BP, wave reflection, circulating plasma NO, and BF% in young obese women with elevated BP. CONCLUSIONS MPT may be an effective intervention for the improvement of vascular function and BF in young obese women with elevated BP, a population at risk for hypertension and early vascular complications. CLINICAL TRIALS REGISTRATION Trial Number NCT03907384

Passive vibration on the legs reduces peripheral and systemic arterial stiffness

Intermittent leg exercise (10 × 1-min sets) with whole-body vibration (WBV) decreases brachial-ankle pulse-wave velocity (baPWV)1 and leg PWV (legPWV) but not aortic PWV.2 As baPWV is an index of systemic arterial stiffness3 mainly influenced by aortic PWV (∼58%) and legPWV (∼23%),4 previously published results1, 2 suggest that WBV affects baPWV through peripheral but not central PWV. The post-exercise decrease in PWV is associated with vasodilation in the exercised limb.5, 6 Similarly, intermittent WBV (3 × 3-min sets)7 or passive vibration (PV)8 has been shown to increase blood flow in the vibrated limb after only 1-min post vibration. Interestingly, 10 min of continuous PV was found to increase arm skin blood flow after 5-min post vibration,9 indicating a direct relationship between the duration of exposure and vasorelaxation. We hypothesized that PV on the legs may decrease legPWV and baPWV more than aortic PWV. The purpose of our study was to examine PWV responses following continuous PV of lengthy duration

Time-dependent heterogeneity leads to transient suppression of the COVID-19 epidemic, not herd immunity

Epidemics generally spread through a succession of waves that reflect factors on multiple timescales. On short timescales, super-spreading events lead to burstiness and overdispersion, while long-term persistent heterogeneity in susceptibility is expected to lead to a reduction in the infection peak and the herd immunity threshold (HIT). Here, we develop a general approach to encompass both timescales, including time variations in individual social activity, and demonstrate how to incorporate them phenomenologically into a wide class of epidemiological models through parameterization. We derive a non-linear dependence of the effective reproduction number Re on the susceptible population fraction S. We show that a state of transient collective immunity (TCI) emerges well below the HIT during early, high-paced stages of the epidemic. However, this is a fragile state that wanes over time due to changing levels of social activity, and so the infection peak is not an indication of herd immunity: subsequent waves can and will emerge due to behavioral changes in the population, driven (e.g.) by seasonal factors. Transient and long-term levels of heterogeneity are estimated by using empirical data from the COVID-19 epidemic as well as from real-life face-to-face contact networks. These results suggest that the hardest-hit areas, such as NYC, have achieved TCI following the first wave of the epidemic, but likely remain below the long-term HIT. Thus, in contrast to some previous claims, these regions can still experience subsequent waves

Effectiveness of Tai Chi on Cardiac Autonomic Function and Symptomatology in Women With Fibromyalgia: A Randomized Controlled Trial

The present study examined the effects of a 12-week Tai Chi (TC) training regimen on heart rate variability (HRV), symptomatology, muscle fitness and body composition in women with fibromyalgia. Participants were randomly assigned to either a TC training group (n = 18) or a control group (n = 19). HRV, symptomatology, muscle fitness and body composition were measured before and after 12 weeks. There were significant decreases (p \u3c 0.05) in sympathovagal balance (LnLF/LnHF), sympathetic tone (LnLF, nLF), pain, and fatigue, and significant increases (p \u3c 0.05) in parasympathetic tone (LnHF, nHF), strength and flexibility following TC compared with no changes after control. The changes in LnLF and LnLF/LnHF were correlated with changes in pain. There were no significant changes in HR, sleep quality and body composition after TC or control. TC may be an effective therapeutic intervention for improving sympathovagal balance, pain, fatigue, strength and flexibility in women with fibromyalgia

The Association of Inflammatory Markers, IL-1α and TGF-β, with Dietary Insulin Load and Dietary Insulin Index in Overweight and Obese Women with Healthy and Unhealthy Metabolic Phenotypes: A Cross-Sectional Study

Context Research has shown IL-1α might play a role in the associations between the MH group and DII and DIL. Objective. We evaluated the association of inflammatory markers, IL-1α and TGF-β, with dietary insulin load and index in women with healthy and unhealthy obesity phenotypes. Materials and Methods. 228 obese/overweight women aged 18–48 years were included in this study. Biochemical factors were obtained from blood samples. Body composition, anthropometric measures, and physical activity assessments were performed. Dietary intakes, DII, and DIL were assessed. Results. Significant associations were observed between the MH group and the DII group (OR = 2.142, 95% CI = 1.421, 2.850, and p = 0.040), in which IL-1α may play a role. Discussion and Conclusion. Significant associations were observed between the MH group and DII. IL-1α might play a role in these associations

Color Diffusion and Conductivity in a Quark-Gluon Plasma

Color diffusion is shown to be an important dissipative property of quark-gluon plasmas that rapidly damps collective color modes. We derive the characteristic color relaxation time scale, $t_c\approx (3\alpha_s T \log(m_E/m_M ))^{-1}$, showing its sensitivity to the ratio of the static color electric and magnetic screening masses. This leads to a surprisingly small color conductivity, $\sigma_c\approx 2 T/\log(m_E/m_M)$, which in fact vanishes in the semi-classical (1-loop) limit.Comment: 11 pages, Columbia University Preprint CU-TP-59

Combined resistance and aerobic exercise training reduces insulin resistance and central adiposity in adolescent girls who are obese: randomized clinical trial

Introduction Exercise training is recommended for improving health and protecting against the development of metabolic and cardiovascular pathologies. Combined resistance and aerobic exercise training (CRAE) has been shown to provide unique benefits in older adults with cardiovascular diseases. Purpose We sought to determine the beneficial effects of CRAE in adolescent girls who are obese and hyperinsulinemic. Methods Forty adolescent girls who are obese (age 14.7 ± 1 years; BMI 30 ± 2) were randomly assigned to a “no exercise” (CON n = 20) or combined exercise group (EX n = 20). The EX group performed resistance and aerobic exercise for 12 weeks, 5 times per week. Exercise intensity was increased gradually, from 40 to 70% of heart rate reserve (HRR), every 4 weeks. The brachial-ankle pulse wave velocity (BaPWV), blood pressure (BP), heart rate (HR), blood leptin, adiponectin levels, and body composition were measured before and after the 12-week intervention. Results We observed that CRAE effectively reduced the body fat percentage, body weight, and waist circumference in the EX group (p \u3c 0.05). After 12 weeks of training, subjects in the CRAE group maintained appropriate leptin and adiponectin levels and showed positive improvements of blood insulin, glucose, and insulin resistance parameters relative to baseline and to the CON group (p \u3c 0.05). Conclusion CRAE is a useful therapeutic method to alleviate metabolic risk factors in adolescent girls who are obese and hyperinsulinemic

The effects of gradual vs. rapid weight loss on serum concentrations of myokines and body composition in overweight and obese females

Research has shown the modulations of Follistatin (FST) and Myostatin (MST) following weight loss. We evaluated the effects of gradual weight loss (GWL) and rapid weight loss (RWL) on serum MST, FST, and body composition in overweight and obese females. Thirty-six overweight and obese females successfully completed the study interventions: GWL (  = 18) or RWL (  = 18). Serum MST and FST concentrations, as well as anthropometric measurements, were collected at baseline and at the conclusion of each weight loss intervention. MST concentration significantly (  < .05) decreased in the GWL; while FST concentration, body fat percentage and skeletal muscle mass significantly declined in both conditions. The loss in skeletal muscle mass was significantly greater in RWL relative to GWL. GWL was more effective than RWL in preserving skeletal muscle mass in overweight and obese females. Moreover, GWL leads to declines in MST concentrations