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Short-term dietary nitrate (NO3−) supplementation has the potential to enhance performance during submaximal endurance, and short-duration, maximal-intensity exercise. However, it has yet to be determined whether NO3− supplementation before and during submaximal endurance exercise can improve performance during a short-duration, maximal-intensity end-sprint. In a randomised, double-blind, crossover study, 9 recreationally active men ingested NO3−-rich (BR: 8 mmol NO3−/day) and NO3−-depleted (PL: 0.75 mmol NO3−/day) beetroot powder for 7 days. On day 7, participants completed 2 h of moderate-intensity cycling, which immediately transitioned into a 60 s maximal-intensity end-sprint, with supplements ingested 2 h before and 1 h into the moderate-intensity exercise bout. Plasma [NO3−] and [NO2−] were higher in BR compared to PL pre- and post-exercise (p < 0.05). Post-exercise plasma [NO3−] was higher than pre-exercise (562 ± 89 µM vs. 300 ± 73 µM; p < 0.05) and plasma [NO2−] was not significantly different pre- (280 ± 58 nM) and post-exercise (228 ± 63 nM) in the BR condition (p > 0.05). Mean power output during the final 30 s of the end-sprint was greater after BR (390 ± 38 W) compared to PL (365 ± 41 W; p < 0.05). There were no differences between BR and PL in any muscle oxygenation variables during moderate-intensity cycling (p > 0.05), but muscle [deoxyhaemoglobin] kinetics was faster during the end-sprint in BR (6.5 ± 1.4 s) compared to PL (7.3 ± 1.4 s; p < 0.05). These findings suggest that NO3− supplementation has the potential to improve end-sprint performance in endurance events when ingested prior to and during exercise. [ABSTRACT FROM AUTHOR]

Our prior observations in normotensive postmenopausal women stimulated the hypotheses that compared with eumenorrheic women, active hypoestrogenic premenopausal women with functional hypothalamic amenorrhea would demonstrate attenuated reflex renin-angiotensin-aldosterone system responses to an orthostatic challenge, whereas to defend blood pressure reflex increases in muscle, sympathetic nerve activity would be augmented. To test these hypotheses, we assessed, in recreationally active women, 12 with amenorrhea (ExFHA; aged 25±1 years; body mass index 20.7±0.7 kg/m²; mean±SEM) and 17 with eumenorrhea (ExOv; 24±1 years; 20.9±0.5 kg/m²), blood pressure, heart rate, plasma renin, angiotensin II, aldosterone, and muscle sympathetic nerve activity at supine rest and during graded lower body negative pressure (-10, -20, and -40 mm Hg). At baseline, heart rate and systolic blood pressure were lower (P<0.05) in ExFHA (47±2 beats/min and 94±2 mm Hg) compared with ExOv (56±2 beats/min and 105±2 mm Hg), but muscle sympathetic nerve activity and renin-angiotensin-aldosterone system constituents were similar (P>0.05). In response to graded lower body negative pressure, heart rate increased (P<0.05) and systolic blood pressure decreased (P<0.05) in both groups, but these remained consistently lower in ExFHA (P<0.05). Lower body negative pressure elicited increases (P<0.05) in renin, angiotensin II, and aldosterone in ExOv, but not in ExFHA (P>0.05). Muscle sympathetic nerve activity burst incidence increased reflexively in both groups, but more so in ExFHA (P<0.05). Otherwise, healthy hypoestrogenic ExFHA women demonstrate low blood pressure and disruption of the normal circulatory response to an orthostatic challenge: plasma renin, angiotensin II, and aldosterone fail to increase and blood pressure is defended by an augmented sympathetic vasoconstrictor response. [ABSTRACT FROM AUTHOR]

The article discusses the polysemous character of the psalms in liturgical recitation. It examines the polysemy of the psalms in liturgical settings. It notes that the recitation of the psalms becomes a performance of memory and hope based on the memorial and eschatological orientation of Judaism and Christianity.

A growing body of literature has examined the role of physical activity (PA) in modifying the effects of estrogen withdrawal on cardiovascular health in postmenopausal women, but the impact of PA on androgens is less clear. Changes in androgen concentrations following regular PA may improve cardiovascular health. This narrative review summarizes the literature assessing the impact of PA interventions on androgens in postmenopausal women. The association between changes in androgen concentrations and cardiovascular health following PA programs is also examined. Randomized controlled trials were included if they (i) implemented a PA program of any type and duration in postmenopausal women and (ii) measured changes in androgen concentrations. Following PA interventions, no changes in androstenedione, conflicting changes in dehydroepiandrosterone/dehydroepiandrosterone-sulfate, and increases in sex hormone-binding globulin concentrations were found. Total testosterone decreased following aerobic PA but increased after resistance training. Most aerobic PA interventions led to reductions in free testosterone. A combination of caloric restriction and/or fat loss enhanced the influence of PA on most androgens. Evidence exploring the relationship between changes in androgens and cardiovascular health indicators was scarce and inconsistent. PA has shown promise in modifying the concentrations of some androgens (free and total testosterone, sex hormone-binding globulin), and remains a well-known beneficial adjuvant option for postmenopausal women to manage their cardiovascular health. Fat loss influences the effect of PA on androgens, but the synergistic role of PA and androgens on cardiovascular health merits further examination. Many research gaps remain regarding the relationship between PA, androgens, and cardiovascular disease in postmenopausal women., (© 2022 The Authors.)

We examined the influence of sex and age on the relationship between aerobic fitness and muscle sympathetic nerve activity (MSNA) in healthy adults. Data were assessed from 224 volunteers (88 females), aged 18-76 yr, in whom resting MSNA (microneurography) and peak oxygen uptake (V̇o 2peak ; incremental exercise test) were evaluated. When separated into younger (<50 yr) and older (≥50 yr) subgroups, there were inverse relationships between relative V̇o 2peak (mL·kg -1 ·min -1 ) and MSNA burst frequency in younger males ( R 2 = 0.21, P < 0.0001) and older females ( R 2 = 0.36, P < 0.01), but not older males ( R 2 = 0.05, P = 0.08) or younger females ( R 2 = 0.03, P = 0.14). Similar patterns were observed with absolute V̇o 2peak (L·min -1 ) and percent-predicted (based on age, sex, weight, height, and modality), and with burst incidence. Sex and age influence the relationship between aerobic fitness and resting MSNA, and, thus, must be considered as key variables when studying these potential associations; inverse relationships are strongest in younger males and older females. NEW & NOTEWORTHY Our data reveal for the first time that associations between aerobic fitness and resting muscle sympathetic nerve activity are sex and age specific; inverse relationships are evident in younger males (<50 yr) and older females (≥50 yr), but absent in younger females (<50 yr) and older males (≥50 yr).

Muscle sympathetic nerve activity (MSNA) decreases during low-intensity dynamic one-leg exercise in healthy subjects but increases in patients with heart failure with reduced ejection fraction (HFrEF). We hypothesized that increased peak oxygen uptake (V̇o 2peak ) after aerobic training would be accompanied by less sympathoexcitation during both mild and moderate one-leg dynamic cycling, an attenuated muscle metaboreflex, and greater skin vasodilation. We studied 27 stable, treated HFrEF patients (6 women; mean age: 65 ± 2 SE yr; mean left ventricular ejection fraction: 30 ± 1%) and 18 healthy age-matched volunteers (6 women; mean age: 57 ± 2 yr). We assessed V̇o 2peak (open-circuit spirometry) and the skin microcirculatory response to reactive hyperemia (laser flowmetry). Fibular MSNA (microneurography) was recorded before and during one-leg cycling (2 min unloaded and 2 min at 50% of V̇o 2peak ) and, to assess the muscle metaboreflex, during posthandgrip ischemia (PHGI). HFrEF patients were evaluated before and after 6 mo of exercise-based cardiac rehabilitation. Pretraining V̇o 2peak and skin vasodilatation were lower ( P < 0.001) and resting MSNA higher ( P = 0.01) in HFrEF than control subjects. Training improved V̇o 2peak (+3.0 ± 1.0 mL·kg -1 ·min -1 ; P < 0.001) and cutaneous vasodilation and diminished resting MSNA (-6.0 ± 2.0, P = 0.01) plus exercise MSNA during unloaded (-4.0 ± 2.5, P = 0.04) but not loaded cycling (-1.0 ± 4.0 bursts/min, P = 0.34) and MSNA during PHGI ( P < 0.05). In HFrEF patients, exercise training lowers MSNA at rest, desensitizes the sympathoexcitatory metaboreflex, and diminishes MSNA elicited by mild but not moderate cycling. Training-induced downregulation of resting MSNA and attenuated reflex sympathetic excitation may improve exercise capacity and survival.

The renin-angiotensin-aldosterone system (RAAS) is integrally involved in multiple cardiovascular physiological processes including arterial blood pressure (BP) regulation. Over activity of the RAAS has been implicated in the pathogenesis of a number of cardiovascular disease entities, including hypertension. Several lines of evidence suggest estrogen favorably modulates the RAAS. Conversely, estrogen deficiency due to menopause may contribute to over activity of the RAAS. Of importance, estrogen deficiency in women is not exclusive to the postmenopausal period. Functional hypothalamic amenorrhea is a reversible cause of premenopausal hypoestrogenemia. In contrast to postmenopausal women (PMW), premenopausal women with exercise-associated functional hypothalamic amenorrhea demonstrate decreased, not increased, resting BP compared with their estrogen-replete eumenorrheic counterpart. In this review we briefly examine the effects of estrogen status on the RAAS and present the hypothesis that the RAAS is altered in physically active women with functional hypothalamic amenorrhea., (Copyright © 2014 the American Physiological Society.)

Context: Evidence indicates that hypoestrogenemia is linked with accelerated progression of atherosclerosis. Premenopausal women presenting with ovulatory disruption due to functional hypothalamic amenorrhea (FHA) are characterized by hypoestrogenemia. One common and reversible form of FHA in association with energy deficiency is exercise-associated amenorrhea (EAA)., Evidence Acquisition: Articles were found via PubMed search for both original and review articles based on peer review publications between 1974 and 2011 reporting on cardiovascular changes in women with FHA, with emphasis placed on women with EAA., Evidence Synthesis: Despite participation in regular exercise training, hypoestrogenic women with EAA demonstrate paradoxical changes in cardiovascular function, including endothelial dysfunction, a known permissive factor for the progression and development of atherosclerosis. Such alterations suggest that the beneficial effects of regular exercise training on vascular function are obviated in the face of hypoestrogenemia. The long-term cardiovascular consequences of altered vascular function in response to ovulatory disruption in women with EAA remain to be determined. Retrospective data, however, suggest premature development and progression of coronary artery disease in older premenopausal women reporting a history of hypothalamic ovulatory disruption. Importantly, in women with EAA, estrogen therapy, folic acid supplementation without change in menstrual status, and resumption of menses restores endothelial function. In this review, we focus on the influence of hypoestrogenemia in association with energy deficiency in mediating changes in cardiovascular function in women with EAA, including endothelial function, regional blood flow, lipid profile, and autonomic control of blood pressure, heart rate, and baroreflex sensitivity. The influence of exercise training is also considered., Conclusion: With the premenopausal years typically considered to be cardioprotective in association with normal ovarian function, ovarian disruption in women with EAA is of importance. Further investigation of the short-term, and potentially long-term, cardiovascular consequences of hypoestrogenemia in women with EAA is recommended.

The cardiovascular consequences of hypoestrogenism in premenopausal women are unclear. Accordingly, the influence of menstrual status and endogenous estrogen (E(2)) exposure on blood pressure (BP), heart rate (HR), and calf blood flow in young (18-35 yr) regularly exercising premenopausal women with exercise-associated menstrual aberrations was investigated. Across consecutive menstrual cycles, daily urinary ovarian steroid levels were analyzed, and the area under the curve was calculated to determine menstrual status and E(2) exposure. BP, HR, blood flow, vascular conductance, and resistance were measured at baseline and following ischemic calf exercise. Exercising subjects consisted of 14 ovulatory (ExOv), 10 short-term (anovulatory and 100 days amenorrhea; LT-E(2) Def) E(2)-deficient women. Nine sedentary ovulatory subjects (SedOv) were also studied. All groups were similar in age (24.8 +/- 0.7 yr), height (164.8 +/- 1.3 cm), weight (57.9 +/- 0.9 kg), and body mass index (21.3 +/- 0.3 kg/m(2)). E(2)-deficient groups had lower (P < 0.002) E(2) exposure compared with ovulatory groups. Resting systolic BP, HR, blood flow, and vascular conductance were lower (P < 0.05) and vascular resistance higher (P < 0.05) in LT-E(2) Def compared with both ovulatory groups. Peak ischemic blood flow, vascular conductance, and HR were also lower (P < 0.05) and vascular resistance higher (P < 0.05) in LT-E(2) Def compared with all other groups. Our findings show that exercising women with long-term E(2) deficiency have impaired regional blood flow and lower systolic BP and HR compared with exercising and sedentary ovulatory women. These cardiovascular alterations represent markers of altered vascular function and autonomic regulation of which the long-term effects remain unknown.