45 research outputs found

    Exercise trained postmenopausal women have higher arterial stiffness than men before and after an acute bout of dynamic exercise

    Get PDF
    Objectives Arterial stiffness, peripheral wave reflection and pulse pressure predict cardiovascular disease risk. Regular aerobic exercise training is a recommended non-pharmacological approach to lower cardiovascular disease risk, including lowering blood pressure and attenuating age-related increases in arterial stiffness (AS). However, it remains unclear whether sex differences differentially modulate vascular adaptations to exercise training and/or influence vascular compliance. Thus, we sought to examine the independent and combined effects of aerobic conditioning and an acute bout of dynamic exercise, a known nitric oxide stimulus, on AS in healthy middle-aged men and postmenopausal women (PMW).Methods Two age-matched (54±1 years; mean±SEM) groups of habitually aerobically trained men (n=6; VO2peak 49.8±1.2 ml/kg/min) and postmenopausal women (n=6; VO2peak 38.5±1.4 ml/kg/min) were studied. Pulse wave analysis using applanation tonometry methods was used to assess arterial stiffness (augmentation pressure [AP; mmHg] and augmentation index corrected for heart rate [AIx75;%]). Central measures of blood pressure (systolic BP, SBP; diastolic BP, DBP; pulse pressure, PP; mmHg) were determined using a validated transfer function. AS and BP were recorded at baseline and 60 min after an acute bout of moderate intensity exercise (45 min of brisk walking at 60% VO2peak).Results Our preliminary findings (see table 1) demonstrate that baseline AP and AIx75 were higher, (p0.05) for baseline measures of central BP but brachial SBP and PP were lower (pConclusions Our preliminary findings suggest that compared with habitually aerobically trained PMW, trained men demonstrate lower peripheral wave reflection yet higher PP amplification both before and after an acute bout of exercise. Associations between PP and AIx75 were observed in men but not women. While the clinical significance of these findings cannot be determined, these observations suggest: i) arterial stiffness is lower in aerobically trained men versus women, and ii) the relationship between PP and arterial stiffness may differ between men and women. Such differences may be of relevance to the known sex differences in the development and progression of hypertension with ageing.</div

    Increased serum adiponectin concentrations in amenorrheic physically active women are associated with impaired bone health but not with estrogen exposure.

    Get PDF
    BACKGROUND: The role of adiponectin in mediating gonadal status and bone health in weight-stable healthy adult female athletes with secondary amenorrhea has not yet been described. METHODS: Using a prospective observational study, age-matched premenopausal women were studied, including 1) sedentary ovulatory women (SedOv; n=10), 2) exercising ovulatory women (ExOv; n=15), and 3) exercising amenorrheic women (ExAmen; n=9). Primary outcome measures included serum total adiponectin and daily urinary estrogen (E1G) levels, expressed as area under the curve (AUC), body fat distribution, and bone mineral density (BMD). Serum leptin, ghrelin, total triiodothyronine (TT3), insulin, and resting energy expenditure (REE) were also determined. RESULTS: The women in this study did not differ in age (25.3±1.4 years; mean ± SEM), height (164±1 cm), weight (57.7±1.0 kg) and BMI (21.5±0.4 kg/m(2)). Exercising women had a higher fat free mass (FFM), lower fat mass (FM) and lower serum leptin concentrations (p<0.05) compared to sedentary women. Adiponectin and ghrelin levels were higher (p<0.05), and TT3 (p=0.019), urinary E1G AUC (p=0.002) lower in ExAmen compared with ExOv and SedOv. Total and L1-L4 BMD were lower (p<0.05) in ExAmen compared with ExOv. Stepwise linear regression identified trunkal FM as the strongest predictor of log adiponectin adjusted for FM (F=23.54, p<0.001). L1-L4 BMD was predicted by log adiponectin and E1G AUC (F=9.856, p=0.045). Total BMD was predicted by log adiponectin (F=7.948, p=0.009). TT3 was the strongest predictor of E1G AUC (F=9.885, p=0.004). CONCLUSIONS: Hypoestrogenic adult female athletes with secondary amenorrhea demonstrate elevated circulating adiponectin relative to FM in association with impaired bone health. Estrogen exposure was predicted by TT3, but not adiponectin. These findings suggest that nutritionally regulated hormones may mediate gonadal status, and that adiponectin and estrogen, either independently or in combination, may mediate bone health in adult amenorrheic physically active women

    The cardiovascular effects of chronic hypoestrogenism in amenorrhoeic athletes: a critical review.

    Get PDF
    In premenopausal women, the most severe menstrual dysfunction is amenorrhoea, which is associated with chronic hypoestrogenism. In postmenopausal women, hypoestrogenism is associated with a number of clinical sequelae related to cardiovascular health. A cardioprotective effect of endogenous oestrogen is widely supported, yet recent studies demonstrate a deleterious effect of hormone replacement therapy for cardiovascular health. What remain less clear are the implications of persistently low oestrogen levels in much younger amenorrhoeic athletes. The incidence of amenorrhoea among athletes is much greater than that observed among sedentary women. Recent data in amenorrhoeic athletes demonstrate impaired endothelial function, elevated low- and high-density lipoprotein levels, reduced circulating nitrates and nitrites, and increased susceptibility to lipid peroxidation. Predictive serum markers of cardiovascular health, such as homocysteine and C-reactive protein, have not yet been assessed in amenorrhoeic athletes, but are reportedly elevated in postmenopausal women. The independent and combined effects of chronic hypoestrogenism and exercise, together with subclinical dietary behaviours typically observed in amenorrhoeic athletes, warrants closer examination. Although no longitudinal studies exist, the altered vascular health outcomes reported in amenorrhoeic athletes are suggestive of increased risk for premature cardiovascular disease. Future research should focus on the presentation and progression of these adverse cardiovascular parameters in physically active women and athletes with hypoestrogenism to determine their effects on long-term health

    Aerobic exercise training in healthy postmenopausal women: effects of hormone therapy

    Get PDF
    OBJECTIVE: We investigated the influence of hormone therapy (HT) on submaximal central and peripheral function in healthy postmenopausal women after 12 weeks of endurance training. METHODS: A randomized, double-blind, placebo-controlled study in a research and clinical facility was conducted. All participants (N = 23) underwent 12 weeks of aerobic exercise training (walking 5 d/wk at 70%-80% peak heart rate [HR]). Eleven participants received HT; 12 received placebo. HT consisted of daily 17beta-estradiol (1 mg) with cyclic micronized progesterone (200 mg) or placebo for 10 days per month. Participants were tested before and after exercise training. Primary outcome measures were submaximal stroke volume, cardiac output, and total peripheral resistance measured during cycling at 30W, 45W, and 60W. Secondary outcome measures were ventilatory threshold, peak oxygen uptake (VO2 peak), and resting and peak-ischemic calf blood flow. RESULTS: At baseline, HT and placebo groups were similar (P > 0.05) in age (mean +/- SEM, 57 +/- 1 y), height (162 +/- 2 cm), weight (72 +/- 4 kg), VO2 peak (21.5 +/- 1.4 mL . kg . min), and all cardiovascular measures. Posttraining oxygen consumption and HR decreased (P 0.05). VO2 peak and oxygen consumption at the ventilatory threshold increased (P < 0.05) within groups. Resting and postischemic blood flow were unaltered. HT did not influence any of the cardiovascular responses. CONCLUSIONS: These findings suggest that in healthy postmenopausal women, 12 weeks of aerobic training is effective in eliciting favorable cardiovascular adaptations, regardless of the presence of short-term HT

    Augmented vagal heart rate modulation in active hypoestrogenic pre-menopausal women with functional hypothalamic amenorrhoea

    Get PDF
    Compared with eumenorrhoeic women, exercise-trained women with functional hypothalamic amenorrhoea (ExFHA) exhibit low heart rates (HRs) and absent reflex renin-angiotensin-system activation and augmentation of their muscle sympathetic nerve response to orthostatic stress. To test the hypothesis that their autonomic HR modulation is altered concurrently, three age-matched (pooled mean, 24 ± 1 years; mean ± S.E.M.) groups of women were studied: active with either FHA (ExFHA; n=11) or eumenorrhoeic cycles (ExOv; n=17) and sedentary with eumenorrhoeic cycles (SedOv; n=17). Blood pressure (BP), HR and HR variability (HRV) in the frequency domain were determined during both supine rest and graded lower body negative pressure (LBNP; -10, -20 and -40 mmHg). Very low (VLF), low (LF) and high (HF) frequency power spectra (ms(2)) were determined and, owing to skewness, log10-transformed. LF/HF ratio and total power (VLF + LF + HF) were calculated. At baseline, HR and systolic BP (SBP) were lower (P0.05). At each stage, HR correlated inversely (P<0.05) with HF. In conclusion, ExFHA women demonstrate augmented vagal yet unchanged sympathetic HR modulation, both at rest and during orthostatic stress. Although the role of oestrogen deficiency is unclear, these findings are in contrast with studies reporting decreased HRV in hypoestrogenic post-menopausal women

    After-exercise heart rate variability is attenuated in postmenopausal women and unaffected by estrogen therapy

    Get PDF
    Delayed heart rate (HR) recovery in the immediate postexercise period has been linked to adverse cardiovascular prognosis. The after effects of an acute bout of exercise on HR modulation in postmenopausal women (PMW) and the influence of estrogen therapy are unknown.In 13 sedentary PMW (54 ± 2 y, mean ± SEM), we assessed HR variability (HRV) -an index of HR modulation-and the influence of estrogen therapy on HRV. HRV in the frequency domain was quantified during supine rest and again 60 minutes after treadmill exercise for 45 minutes, at 60% VO2peak. PMW were studied before and after 4 weeks of oral estradiol. To obtain reference values for the after effects of exercise on HRV in healthy young women, 14 premenopausal women (PreM) completed the identical exercise protocol.Compared with PreM, PMW demonstrated lower high frequency (vagal modulation) and total HRV (P < 0.05) at rest. In PreM, all HRV values were similar before and after exercise. In contrast, in PMW after exercise, despite having identical HR to PreM, high frequency and total HRV were all lower (all P ≤ 0.01) compared with pre-exercise HRV values. Estrogen therapy had no effect on pre or postexercise values for HRV.When compared with PreM, PMW have identical HR, but lower vagal HR modulation at rest and delayed HRV recovery after exercise. Estrogen does not restore baseline HRV or accelerate HRV recovery postexercise, suggesting aging rather than estrogen deficiency per se may lower HRV in PMW

    The effects of short-stature-for-age on cardiovascular and metabolic health in children: a systematic review.

    Get PDF
    Short stature has been associated with coronary heart disease in adults (Paajanen et al, 2010), but similar effects have not been established in children. We aim to identify cardiovascular and metabolic health indicators that are associated with height-for-age in children. These consist of any measures of cardiovascular health and metabolic syndrome such as, but not limited to: abdominal obesity; atherogenic dyslipidaemia; hypertension; hyperglycaemia; insulin resistance; body-mass-index, height-adjusted fat mass, pulse rate, insulin-resistance, triglycerides, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and structural and electrical cardiac dysfunction

    Discordant orthostatic reflex renin-angiotensin and sympathoneural responses in premenopausal exercising-hypoestrogenic women

    Get PDF
    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/m(2); mean ± SEM) and 17 with eumenorrhea (ExOv; 24 ± 1 years; 20.9 ± 0.5 kg/m(2)), 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 (P0.05). In response to graded lower body negative pressure, heart rate increased (P0.05). 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
    corecore