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Background and aims: Cardiovascular disease remains a leading cause of mortality, with statins widely used to reduce its risk. Despite extensive research, the nuanced impact of statin therapy on cardiorespiratory fitness, particularly the reduction in peak oxygen consumption (VO2), is still an open question. This study aims to contribute fresh insights to the ongoing discussion, highlighting the unresolved nature of this clinical matter. Methods: We retrospectively analyzed maximal cardiopulmonary exercise test (CPET) in male and female participants over 18 years of age who were under statins treatment. They were categorized as physically active or inactive according to self-report of physical activity. From 33,804 CPET, 4,941 participants (76 % men, age 42 ± 13 years; and 24 % women, age 41 ± 13 years) were included in the study. Results: The multivariate linear regression model showed that statins were associated with a significant reduction in VO2 peak (-4.2 [-4.8, -3.5] mL/kg/min, p < 0.01) after adjusting for age, sex, use of beta-blockers, antiarrhythmics, presence of diabetes, and weekly level of physical activity. This reduction in VO2 peak was attenuated in participants with higher weekly physical activity volume (150 to 300 min/week: 3.2 [2.7; 3.7] mL/kg/min; 301 to 600 min/week: 4.5 [3.7; 5.3] mL/kg/min; and > 600 min/week: 6.9 [5.4; 8.4] mL/kg/min, all p < 0.01). Conclusions: Statin use is associated with a lower VO2 peak in adults. However, this adverse effect appears to be mitigated by engaging in regular physical activity (>150 min/week). Future research should explore the mechanisms behind this interaction and identify optimal exercise regimens for individuals on statin therapy.
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Sarcopenia is an emerging clinical condition determined by the reduction in physical function and muscle mass, being a health concern since it impairs quality of life and survival. Exercise training is a well-known approach to improve physical capacities and body composition, hence managing sarcopenia progression and worsening. However, it may be an ineffective treatment for many elderly with exercise-intolerant conditions. Thus, the use of anabolic-androgenic steroids (AAS) may be a plausible strategy, since these drugs can increase physical function and muscle mass. The decision to initiate AAS treatment should be guided by an evidence-based patient-centric perspective, once the balance between risks and benefits may change depending on the clinical condition coexisting with sarcopenia. This mini-review points out a critical appraisal of evidence and limitation of exercise training and AAS to treat sarcopenia.
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Anabolic androgenic steroid (AAS) abuse leads to myocardial toxicity. Human studies are conflicting about the myocardial fibrosis in AAS users. We evaluated cardiac tissue characterization, left ventricle (LV) function, and cardiac structure by cardiovascular magnetic resonance (CMR). Twenty strength-trained AAS users (AASU) aged 29±5 yr, 20 strength-trained AAS nonusers (AASNU), and 7 sedentary controls (SC) were enrolled. Native T1 mapping, late-gadolinium enhancement (LGE), extracellular volume (ECV), and myocardial strain were evaluated. AASU showed lower Native T1 values than AASNU (888±162 vs. 1020±179 ms p=0.047). Focal myocardial fibrosis was found in 2 AASU. AASU showed lower LV radial strain (30±8 vs. 38±6%, p<0.01), LV circumferential strain (-17±3 vs. -20±2%, p<0.01), and LV global longitudinal strain (-17±3 vs. -20±3%, p<0.01) than AASNU by CMR. By echocardiography, AASU demonstrated lower 4-chamber longitudinal strain than AASNU (-15±g3 vs. -18±2%, p=0.03). ECV was similar among AASU, AASNU, and SC (28±10 vs. 28±7 vs. 30±7%, p=0.93). AASU had higher LV mass index than AASNU and SC (85±14 vs. 64±8 vs. 58±5 g/m2, respectively, p<0.01). AAS abuse may be linked to decreased myocardial native T1 values, impaired myocardial contractility, and focal fibrosis. These alterations may be associated with maladaptive cardiac hypertrophy in young AAS users.
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Meios de Contraste , Gadolínio , Estudos de Casos e Controles , Fibrose , Humanos , Miocárdio , Valor Preditivo dos Testes , Congêneres da Testosterona/efeitos adversos , Função Ventricular EsquerdaRESUMO
OBJECTIVES: We compared physical activity levels before the outbreak and quarantine measures with COVID-19-associated hospitalization prevalence in surviving patients infected with SARS-CoV-2. Additionally, we investigated the association of physical activity levels with symptoms of the disease, length of hospital stay, and mechanical ventilation. DESIGN: Observational, cross-sectional. METHODS: Between June 2020 and August 2020, we invited Brazilian survivors and fully recovered patients infected with SARS-CoV-2 to respond to an online questionnaire. We shared the electronic link to the questionnaire on the internet. We collected data about clinical outcomes (symptoms, medications, hospitalization, and length of hospital stay) and cofactors, such as age, sex, ethnicity, preexisting diseases, socioeconomic and educational, and physical activity levels using the International Physical Activity Questionnaire (IPAQ short version). RESULTS: Out of 938 patients, 91 (9.7%) were hospitalized due to COVID-19. In a univariate analysis, sex, age, and BMI were all associated with hospitalizations due to COVID-19. Men had a higher prevalence of hospitalization (66.6%, pâ¯=â¯0.013). Patients older than 65â¯years, obese, and with preexisting disease had a higher prevalence of COVID-19-related hospitalizations. In a multivariate regression model, performance of at least 150â¯min/wk (moderate) and/or 75â¯min/wk (vigorous) physical activity was associated with a lower prevalence of hospitalizations after adjustment for age, sex, BMI, and preexisting diseases (PRâ¯=â¯0.657; pâ¯=â¯0.046). CONCLUSIONS: Sufficient physical activity levels were associated with a lower prevalence of COVID-19-related hospitalizations. Performing at least 150â¯min a week of moderate-intensity, or 75â¯min a week of vigorous-intensity physical activity was associated with 34.3% reduction in prevalence.
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COVID-19/epidemiologia , Exercício Físico , Comportamentos Relacionados com a Saúde , Hospitalização/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , COVID-19/diagnóstico , COVID-19/etiologia , COVID-19/terapia , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Proteção , Quarentena , Respiração Artificial/estatística & dados numéricos , Fatores de Risco , Índice de Gravidade de Doença , Sobreviventes , Adulto JovemRESUMO
AIMS: Patients with Chagas disease and heart failure (HF) have a poor prognosis similar to that of patients with ischaemic or dilated cardiomyopathy. However, the impact of body composition and muscle strength changes in these aetiologies is still unknown. We aimed to evaluate these parameters across aetiologies in two distinct cohort studies [TESTOsterone-Heart Failure trial (TESTO-HF; Brazil) and Studies Investigating Co-morbidities Aggravating Heart Failure (SICA-HF; Germany)]. METHODS AND RESULTS: A total of 64 male patients with left ventricular ejection fraction ≤40% were matched for body mass index and New York Heart Association class, including 22 patients with Chagas disease (TESTO-HF; Brazil), and 20 patients with dilated cardiomyopathy and 22 patients with ischaemic heart disease (SICA-HF; Germany). Lean body mass (LBM), appendicular lean mass (ALM), and fat mass were assessed by dual energy X-ray absorptiometry. Sarcopenia was defined as ALM divided by height in metres squared <7.0 kg/m2 (ALM/height2 ) and handgrip strength cut-off for men according to the European Working Group on Sarcopenia in Older People. All patients performed maximal cardiopulmonary exercise testing. Forearm blood flow (FBF) was measured by venous occlusion plethysmography. Chagasic and ischaemic patients had lower total fat mass (16.3 ± 8.1 vs. 19.3 ± 8.0 vs. 27.6 ± 9.4 kg; P < 0.05) and reduced peak oxygen consumption (VO2 ) (1.17 ± 0.36 vs. 1.15 ± 0.36 vs. 1.50 ± 0.45 L/min; P < 0.05) than patients with dilated cardiomyopathy, respectively. Chagasic patients showed a trend towards decreased LBM when compared with ischaemic patients (48.3 ± 7.6 vs. 54.2 ± 6.3 kg; P = 0.09). Chagasic patients showed lower handgrip strength (27 ± 8 vs. 37 ± 11 vs. 36 ± 14 kg; P < 0.05) and FBF (1.84 ± 0.54 vs. 2.75 ± 0.76 vs. 3.42 ± 1.21 mL/min/100 mL; P < 0.01) than ischaemic and dilated cardiomyopathy patients, respectively. There was no statistical difference in the distribution of sarcopenia between groups (P = 0.87). In addition, FBF correlated positively with LBM (r = 0.31; P = 0.012), ALM (r = 0.25; P = 0.046), and handgrip strength (r = 0.36; P = 0.004). In a logistic regression model using peak VO2 as the dependent variable, haemoglobin (odds ratio, 1.506; 95% confidence interval, 1.043-2.177; P = 0.029) and ALM (odds ratio, 1.179; 95% confidence interval, 1.011-1.374; P = 0.035) were independent predictors for peak VO2 adjusted by age, left ventricular ejection fraction, New York Heart Association, creatinine, and FBF. CONCLUSIONS: Patients with Chagas disease and HF have decreased fat mass and exhibit reduced peripheral blood flow and impaired muscle strength compared with ischaemic HF patients. In addition, patients with Chagas disease and HF show a tendency to have greater reduction in total LBM, with ALM remaining an independent predictor of reduced functional capacity in these patients. The percentage of patients affected by sarcopenia was equal between groups.
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Doença de Chagas , Insuficiência Cardíaca , Idoso , Brasil/epidemiologia , Alemanha , Força da Mão , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Força Muscular , Músculos , Volume Sistólico , Testosterona/análogos & derivados , Função Ventricular EsquerdaRESUMO
AIMS: We studied the association between android (A) to gynoid (G) fat ratio and functional capacity (peak VO2 ) in male patients with heart failure with reduced ejection fraction (HFrEF). METHODS AND RESULTS: We enrolled 118 male patients with HFrEF with left ventricular ejection fraction (LVEF) <40%. Body composition (by using dual x-ray absorptiometry) and peak VO2 (by cardiopulmonary exercise testing) were measured. Sarcopenic obesity was defined according to the Foundation for the National Institutes of Health criteria (FNIH). Blood sample for metabolic and hormonal parameters were measured. Fifteen patients (12.7%) showed sarcopenic obesity (body mass index > 25 kg/m2 with FNIH index < 0.789). The median A/G ratio was 0.55. A/G ratio > 0.55 was detected in 60 patients. Relative peak VO2 was lower in patients with A/G ratio > 0.55 than in patients with A/G ratio <0.55 (18.7 ± 5.3 vs. 22.5 ± 6.1 mL/kg/min, P < 0.001). Logistic regression analysis showed A/G ratio >0.55 to be independently associated with reduced peak VO2 adjusted for age, body mass index, LVEF, presence of sarcopenia, anabolic hormones, and haemoglobin (odds ratio 3.895, 95% confidence interval 1.030-14.730, P = 0.045). CONCLUSIONS: Body fat distribution, particularly android and gynoid fat composition, together with other cofactors, might have an important adverse role on functional capacity in male patients with HFrEF. Future studies are needed to address possible mechanisms involved in this relationship.
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Insuficiência Cardíaca , Absorciometria de Fóton , Distribuição da Gordura Corporal , Humanos , Masculino , Volume Sistólico , Estados Unidos , Função Ventricular EsquerdaRESUMO
AIMS: The definition of sarcopenia based on appendicular lean mass/height (2) (ALM/height (2) ) is often used, although it can underestimate the prevalence of sarcopenia in overweight/obese patients with heart failure. Therefore, new methods have been proposed to overcome this limitation. We aimed to evaluate the prevalence of sarcopenia by three methods and compare body composition in this population. METHODS AND RESULTS: We enrolled 168 male patients with heart failure (left ventricular ejection fraction <40%). Sixty-six patients (39.3%) were identified with sarcopenia by at least one method. The lower 20th percentile defined as the cut-off point for sarcopenia was 7.03 kg/m2 , -2.32 and 0.76 for Baumgartner's (20.8%), Newman's (21.4%), and Studenski's methods (21.4%), respectively. Patients with body mass index (BMI) <25 kg/m2 were more likely to be identified by Baumgartner's than Studenski's method (P < 0.001). However, in patients with BMI ≥ 25 kg/m2 , Studenski's and Newman's methods were more likely to detect sarcopenia than Baumgartner's method (both P < 0.005). Patients were further divided into three subgroups: (i) patients classified in all indexes (n = 8), (ii) patients classified in Baumgartner's (sarcopenic; n = 27), and (iii) patients classified in both Newman's and Studenski's methods (sarcopenic obesity; n = 31). Comparing body composition among groups, all sarcopenic groups presented lower total lean mass compared with non-sarcopenic patients, whereas sarcopenic obese patients had higher total lean mass than lean sarcopenic patients. CONCLUSIONS: Our results demonstrate that the prevalence of sarcopenia in overweight/obese patients is similar to lean sarcopenic patients when other methods are considered. In patients with higher BMI, Studenski's method seems to be more feasible to detect sarcopenia.
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Insuficiência Cardíaca , Obesidade , Sobrepeso , Sarcopenia , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Índice de Massa Corporal , Feminino , Força da Mão , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Obesidade/complicações , Sobrepeso/complicações , Sarcopenia/complicações , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Volume Sistólico , Função Ventricular EsquerdaRESUMO
Disturbed shear rate (SR), characterized by increased retrograde and oscillatory SR in the brachial artery, is associated with inflammation, atherosclerosis, endothelial dysfunction, and sympathetic hyperactivity. Young subjects do not have disturbed SR; however, elderly subjects do, which seems to be associated with sympathetic hyperactivity. Anabolic androgenic steroids (AAS) abuse in young is associated with increased muscle sympathetic nerve activity (MSNA). We hypothesized that AAS users might have disturbed SR. We tested the association between retrograde and oscillatory SR with MSNA. In addition, we measured the high-sensitivity C-reactive protein (hs-CRP). We evaluated 10 male AAS users, age 27 ± 4 years, and 10 age-matched AAS nonusers, age 29 ± 5 years. At rest, retrograde and oscillatory SR were evaluated by Doppler ultrasound, MSNA was measured with microneurography, and hs-CRP was measured in blood sample. Flow-mediated dilation (FMD) was also assessed. AAS users had higher retrograde SR (24.42 ± 17.25 vs 9.15 ± 6.62 s- 1 , P = 0.01), oscillatory SR (0.22 ± 0.13 vs 0.09 ± 0.07 au P = 0.01), and MSNA (42 ± 9 vs 32 ± 4 bursts/100 heart beats, P = 0.018) than nonusers. MSNA (bursts/100 heart beats) was correlated with retrograde SR (r = 0.50, P = 0.050) and oscillatory SR (r = 0.51, P = 0.042). AAS users had higher hs-CRP [1.17 (0.44-3.63) vs 0.29 (0.17-0.70) mg/L, P = 0.015] and decreased FMD (6.42 ± 2.07 vs 8.28% ± 1.53%, P = 0.035) than nonusers. In conclusion, AAS abuse is associated with retrograde and oscillatory SR which were associated with augmented sympathetic outflow. In addition, AAS seems to lead to inflammation characterized by increased hs-CRP. These alterations may have the potential of increasing the early risk of atherosclerotic disease in young AAS users.
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Anabolizantes/efeitos adversos , Artéria Braquial/fisiopatologia , Esteroides/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Adulto , Aterosclerose , Proteína C-Reativa/análise , Estudos de Casos e Controles , Estudos Transversais , Frequência Cardíaca , Humanos , Masculino , Oscilometria , Fatores de Risco , Sistema Nervoso Simpático , Adulto JovemRESUMO
PURPOSE: Increased resting muscle sympathetic nerve activity (MSNA) and lower forearm blood flow (FBF) were observed in young men who use anabolic androgenic steroids (AAS). However, the response of MSNA and FBF in AAS users triggered by muscle mechanoreflex and central command has never been tested. In addition, we evaluated the blood pressure (BP) and heart rate (HR) responses during these maneuvers. METHODS: Nineteen AAS users (AASU) 31 ± 6 yr of age and 18 AAS nonusers (AASNU) 29 ± 4 yr of age were recruited. All participants were involved in strength training. AAS use was determined using a urine test (liquid chromatography with tandem mass spectrometry). MSNA was measured using the microneurography technique. FBF was measured by using venous occlusion plethysmography. BP was measured using an automatic oscillometric device. HR was recorded continuously through ECG. Isometric handgrip exercise was performed at 30% of the maximal voluntary contraction for 3 min, and mental stress was elicited by the Stroop color-word test for 4 min. RESULTS: The MSNA and FBF responses during exercise were similar between AASU and AASNU, with a trend toward higher MSNA (bursts per minute; P = 0.084) and lower forearm vascular conductance (FVC; units; P = 0.084) in AASU than in AASNU. During mental stress, AASU showed a significantly higher MSNA (P < 0.05) and lower FBF (P < 0.05) compared with AASNU. During both maneuvers, HR and BP increased linearly in both groups; however, AASU showed a significantly higher HR compared with AASNU. CONCLUSIONS: During muscle mechanoreflex activation (isometric exercise), AASU have normal MSNA and FBF responses, whereas during central command (mental stress) stimulation, AASU have exacerbated MSNA and blunted vasodilation. Therefore, mental stress seems to exacerbate neurovascular control throughout stress reaction situations in AASU.
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Exercício Físico/fisiologia , Hemodinâmica , Estresse Psicológico , Sistema Nervoso Simpático , Congêneres da Testosterona/administração & dosagem , Adulto , Pressão Sanguínea , Antebraço/irrigação sanguínea , Força da Mão , Frequência Cardíaca , Humanos , Masculino , Pletismografia , Fluxo Sanguíneo Regional , VasodilataçãoRESUMO
The objective of this study was to evaluate cardiac autonomic control and muscle vasodilation response during isometric exercise in sedentary and physically active older adults. Twenty healthy participants, 10 sedentary and 10 physically active older adults, were evaluated and paired by gender, age, and body mass index. Sympathetic and parasympathetic cardiac activity (spectral and symbolic heart rate analysis) and muscle blood flow (venous occlusion plethysmography) were measured for 10 minutes at rest (baseline) and during 3 minutes of isometric handgrip exercise at 30% of the maximum voluntary contraction (sympathetic excitatory maneuver). Variables were analyzed at baseline and during 3 minutes of isometric exercise. Cardiac autonomic parameters were analyzed by Wilcoxon and Mann-Whitney tests. Muscle vasodilatory response was analyzed by repeated-measures analysis of variance followed by Tukey's post hoc test. Sedentary older adults had higher cardiac sympathetic activity compared to physically active older adult subjects at baseline (63.13±3.31 vs 50.45±3.55 nu, P=0.02). The variance (heart rate variability index) was increased in active older adults (1,438.64±448.90 vs 1,402.92±385.14 ms, P=0.02), and cardiac sympathetic activity (symbolic analysis) was increased in sedentary older adults (5,660.91±1,626.72 vs 4,381.35±1,852.87, P=0.03) during isometric handgrip exercise. Sedentary older adults showed higher cardiac sympathetic activity (spectral analysis) (71.29±4.40 vs 58.30±3.50 nu, P=0.03) and lower parasympathetic modulation (28.79±4.37 vs 41.77±3.47 nu, P=0.03) compared to physically active older adult subjects during isometric handgrip exercise. Regarding muscle vasodilation response, there was an increase in the skeletal muscle blood flow in the second (4.1±0.5 vs 3.7±0.4 mL/min per 100 mL, P=0.01) and third minute (4.4±0.4 vs 3.9±0.3 mL/min per 100 mL, P=0.03) of handgrip exercise in active older adults. The results indicate that regular physical activity improves neurovascular control of muscle blood flow and cardiac autonomic response during isometric handgrip exercise in healthy older adult subjects.
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Sistema Nervoso Autônomo/fisiologia , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Fatores Etários , Idoso , Índice de Massa Corporal , Feminino , Força da Mão/fisiologia , Frequência Cardíaca/fisiologia , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/irrigação sanguínea , Sistema Nervoso Parassimpático/fisiologia , Comportamento Sedentário , Fatores Sexuais , Sistema Nervoso Simpático/fisiologia , Vasodilatação/fisiologiaRESUMO
We described recently that systemic hypoxia provokes vasoconstriction in heart failure (HF) patients. We hypothesized that either the exaggerated muscle sympathetic nerve activity and/or endothelial dysfunction mediate the blunted vasodilatation during hypoxia in HF patients. Twenty-seven HF patients and 23 age-matched controls were studied. Muscle sympathetic nerve activity was assessed by microneurography and forearm blood flow (FBF) by venous occlusion plethysmography. Peripheral chemoreflex control was evaluated through the inhaling of a hypoxic gas mixture (10% O(2) and 90% N(2)). Basal muscle sympathetic nerve activity was greater and basal FBF was lower in HF patients versus controls. During hypoxia, muscle sympathetic nerve activity responses were greater in HF patients, and forearm vasodilatation in HF was blunted versus controls. Phentolamine increased FBF responses in both groups, but the increase was lower in HF patients. Phentolamine and N(G)-monomethyl-l-arginine infusion did not change FBF responses in HF but markedly blunted the vasodilatation in controls. FBF responses to hypoxia in the presence of vitamin C were unchanged and remained lower in HF patients versus controls. In conclusion, muscle vasoconstriction in response to hypoxia in HF patients is attributed to exaggerated reflex sympathetic nerve activation and blunted endothelial function (NO activity). We were unable to identify a role for oxidative stress in these studies.
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Células Quimiorreceptoras/fisiologia , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Músculo Liso Vascular/inervação , Músculo Liso Vascular/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Vasodilatação/fisiologia , Adulto , Ácido Ascórbico/farmacologia , Estudos de Casos e Controles , Antebraço/irrigação sanguínea , Hemodinâmica/fisiologia , Humanos , Hipóxia/fisiopatologia , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Fentolamina/farmacologia , Sistema Nervoso Simpático/fisiopatologia , Vasoconstrição/efeitos dos fármacos , Vasoconstrição/fisiologia , Vasodilatação/efeitos dos fármacos , ômega-N-Metilarginina/farmacologiaRESUMO
PURPOSE: Previous studies showed that anabolic androgenic steroids (AAS) increase vascular resistance and blood pressure (BP) in humans. In this study, we tested the hypotheses 1) that AAS users would have increased muscle sympathetic nerve activity (MSNA) and reduced forearm blood flow (FBF) compared with AAS nonusers and 2) that there would be an association between MSNA and 24-h BP. METHODS: Twelve AAS users aged 31 +/- 2 yr (means +/- SE) and nine age-matched AAS nonusers aged 29 +/- 2 yr participated in the study. All individuals were involved in strength training for at least 2 yr. AAS was determined by urine test (chromatography-mass spectrometry). MSNA was directly measured by microneurography technique. FBF was measured by venous occlusion plethysmography. BP monitoring consisted of measures of BP for 24 h. RESULTS: MSNA was significantly higher in AAS users than that in AAS nonusers (29 +/- 3 vs 20 +/- 1 bursts per minute, P = 0.01). FBF (1.92 +/- 0.17 vs 2.77 +/- 0.24 mL x min(-1) x 100 mL(-1), P = 0.01) and forearm vascular conductance (2.01 +/- 0.17 vs 2.86 +/- 0.31 U, P = 0.02) were significantly lower in AAS users than that in AAS nonusers. Systolic (131 +/- 4 vs 120 +/- 3 mm Hg, P = 0.001), diastolic (74 +/- 4 vs 68 +/- 3 mm Hg, P = 0.02), and mean BP (93 +/- 4 vs 86 +/- 3 mm Hg, P = 0.005) and heart rate (74 +/- 3 vs 68 +/- 3 bpm, P = 0.02) were significantly higher in AAS users when compared with AAS nonusers. Further analysis showed that there was a significant correlation between MSNA and 24-h mean BP (r = 0.75, P = 0.002). CONCLUSIONS: AAS increases MSNA and reduces muscle blood flow in young individuals. In addition, the increase in BP levels in AAS users is associated with augmented sympathetic outflow. These findings suggest that AAS increases the susceptibility for cardiovascular disease in humans.