RESUMO
A key mechanism promoting vascular endothelial dysfunction is mitochondrial-derived reactive oxygen species (mtROS). Aerobic exercise preserves endothelial function in preclinical models by lowering mtROS. However, the effects of mtROS on endothelial function in exercising and non-exercising adults is limited. In a double-blind, randomized, placebo-controlled crossover study design 23 (10 M/13 F, age 62.1 ± 11.5 years) middle-aged and older (MA/O, ≥45 years) adults were divided into two groups: exercisers (EX, n = 11) and non-exercisers (NEX, n = 12). All participants had endothelial function (brachial artery flow-mediated dilatation, FMDBA) measured before and â¼1 h after mitoquinone mesylate (MitoQ) (single dose, 80 mg) and placebo supplementation. A two-way repeated measures ANOVA was used to determine the effects of MitoQ and placebo on FMDBA. Pearson correlations assessed the association between the change in FMDBA with MitoQ and baseline FMDBA and cardiorespiratory fitness (CRF). Compared with placebo, MitoQ increased FMDBA in NEX by + 2.1% (MitoQ pre: 4.9 ± 0.4 vs. post: 7.0 ± 0.4 %, P = 0.004, interaction) but not in EX (P = 0.695, interaction). MitoQ also increased endothelial function in adults with a FMDBA <6% (P < 0.0001, interaction) but not >6% (P = 0.855, interaction). Baseline FMDBA and CRF were correlated (r = 0.44, P = 0.037), whereas the change in FMDBA with MitoQ was inversely correlated with CRF (r = -0.66, P < 0.001) and baseline FMDBA (r = -0.73, P < 0.0001). The relationship between the change in FMDBA and baseline FMDBA remained correlated after adjusting for CRF (r = -0.55, P = 0.007). These data demonstrate that MitoQ acutely improves FMDBA in NEX and EX adults who have a baseline FMDBA <6%. KEY POINTS: A key age-related change contributing to increased cardiovascular disease (CVD) risk is vascular endothelial dysfunction due to increased mitochondrial-derived reactive oxygen species (mtROS). Aerobic exercise preserves endothelial function via suppression of mtROS in preclinical models but the evidence in humans is limited. In the present study, a single dose of the mitochondria-targeted antioxidant, mitoquinone mesylate (MitoQ), increases endothelial function in non-exercisers with lower cardiorespiratory fitness (CRF) but not in exercisers with higher CRF. The acute effects of MitoQ on endothelial function in middle-aged and older adults (MA/O) are influenced by baseline endothelial function independent of CRF. These data provide initial evidence that the acute MitoQ-enhancing effects on endothelial function in MA/O adults are influenced, in part, via CRF and baseline endothelial function.
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Artéria Braquial , Aptidão Cardiorrespiratória , Estudos Cross-Over , Endotélio Vascular , Compostos Organofosforados , Ubiquinona , Ubiquinona/análogos & derivados , Humanos , Masculino , Ubiquinona/farmacologia , Pessoa de Meia-Idade , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Feminino , Idoso , Compostos Organofosforados/farmacologia , Método Duplo-Cego , Artéria Braquial/efeitos dos fármacos , Artéria Braquial/fisiologia , Vasodilatação/efeitos dos fármacos , Exercício Físico/fisiologiaRESUMO
Aortic perivascular adipose tissue (aPVAT) density is associated with age-related aortic stiffness in humans and therefore, may contribute to cardiovascular dysfunction. A lower subendocardial viability ratio (SEVR), an estimate of myocardial perfusion, indicates greater cardiovascular disease (CVD) risk and is associated with aortic stiffness in clinical populations. However, the influence of aortic stiffness on the relation between aPVAT density and SEVR/cardiovascular (CV) hemodynamics in apparently healthy adults are unknown. We hypothesize greater aPVAT density will be associated with lower SEVR and higher CV hemodynamics independent of aortic stiffness. Fourteen (6M/8F, mean age 55.4 ± 5.6 y, body mass index 25.5 ± 0.6 kg/m2) adults completed resting measures of myocardial perfusion (SEVR), CV hemodynamics (pulse wave analysis), aortic stiffness (carotid-femoral pulse wave velocity [cfPWV]), and a computed tomography scan to acquire aPVAT and visceral adipose tissue (VAT) density. Greater aPVAT density (i.e. higher density) was associated with lower SEVR (r=-0.78, p<0.001) and a higher systolic pressure time integral (r=0.49, p=0.03), forward pulse height (r=0.49, p=0.03), reflected pulse height (r=0.55, p=0.02), ejection duration (r=0.56, p=0.02) and augmentation pressure (r=0.69, p=0.003), but not with the diastolic pressure time integral (r=-0.22, p=0.22). VAT density was not associated with SEVR or any CV hemodynamic endpoints (all, p>0.05). Further, the relation between aPVAT density and SEVR remained after adjusting for aortic stiffness (r=-0.66, p=0.01) but not age (r=-0.24, p>0.05). These data provide initial evidence for aPVAT as a novel yet understudied local fat depot contributing to lower myocardial perfusion in apparently healthy adults with aging.
RESUMO
Cardiorespiratory fitness (CRF) and the subendocardial viability ratio (SEVR) decline with age and predict future cardiovascular disease (CVD) events in a sex-dependent manner. However, the relation between CRF and SEVR in apparently healthy males and females across the age span is largely unknown. We hypothesized higher CRF is associated with greater SEVR in older females but not in males. Two-hundred sixty-two (126 M/136 F, age range 20-84 yr) participants underwent measures of CRF (maximal O2 consumption, VÌo2max) and SEVR (pulse wave analysis, PWA). A two-way analysis of variance (ANOVA) was used to examine differences in baseline characteristics between younger (<45 yr) and middle-aged and older (MA/O, ≥45 yr) males and females. Bivariate correlations assessed the relation between CRF, SEVR, and age in males and females. Partial correlations adjusted for CVD risk factors and medications. MA/O females had the lowest CRF and SEVR compared with all other groups (P < 0.05, both). SEVR was negatively correlated with age (r = -0.29) and positively correlated with CRF (r = 0.53) in females (P < 0.05, both) that persisted after controlling for CVD risk factors and medications (P < 0.05, all). SEVR was correlated with CRF in males only after adjusting for CVD risk factors and medications (r = 0.26, P < 0.05). These findings collectively demonstrate higher CRF is associated with greater SEVR in males and females after adjusting for CVD risk factors and medications, therefore highlighting subtle sex-specific nuances that warrant further investigation.NEW & NOTEWORTHY Cardiorespiratory fitness (CRF) and the subendocardial viability ratio (SEVR) are independent predictors of mortality and decline with age. However, the sex-specific relationship between CRF and SEVR with aging in adult males and females is unknown. Our findings demonstrate higher CRF is associated with greater age-related SEVR in males and females, after adjusting for traditional cardiovascular disease (CVD) risk factors and medications. However, subtle sex-related nuances exist in the relationship between SEVR and CRF that require further investigation.
Assuntos
Aptidão Cardiorrespiratória , Doenças Cardiovasculares , Adulto , Pessoa de Meia-Idade , Masculino , Feminino , Humanos , Idoso , Adulto Jovem , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/etiologia , Envelhecimento , Nível de Saúde , Perfusão/efeitos adversosRESUMO
PURPOSE OF REVIEW: Examine the current state of literature related to the impact of obesity in children and adolescents on health-related physical fitness and the resultant cardiometabolic disease risk. RECENT FINDINGS: Cardiorespiratory fitness of children and adolescents has declined over the past few decades which corresponds with an increase in obesity rates. Children with obesity are more likely to have low cardiorespiratory fitness which is associated with higher cardiometabolic disease risk and poorer mental health. The impact of obesity on muscular fitness in children and adolescents is more difficult to ascertain, but in general measures of physical function are lower in children with obesity which has also been associated with higher cardiometabolic disease risk. Components of health-related physical fitness are trending negatively in children and adolescents and appear to be related to the increase in prevalence of obesity. The resultant cardiometabolic disease risk has also risen which suggests a greater disease burden in the future. These disparaging findings highlight the need for aggressive interventions to improve physical fitness in children and adolescents.
Assuntos
Aptidão Cardiorrespiratória , Obesidade Infantil , Aptidão Física , Humanos , Adolescente , Criança , Obesidade Infantil/fisiopatologia , Obesidade Infantil/complicações , Aptidão Cardiorrespiratória/fisiologia , Aptidão Física/fisiologia , Doenças Cardiovasculares/fisiopatologia , Fatores de Risco Cardiometabólico , Fatores de Risco , Exercício Físico/fisiologia , Músculo Esquelético/fisiopatologiaRESUMO
Several factors affect muscle protein synthesis (MPS) in the postabsorptive state. Extreme physical inactivity (e.g., bedrest) may reduce basal MPS, whereas walking may augment basal MPS. We hypothesized that outpatients would have a higher postabsorptive MPS than inpatients. To test this hypothesis, we conducted a retrospective analysis. We compared 152 outpatient participants who arrived at the research site the morning of the MPS assessment with 350 Inpatient participants who had an overnight stay in the hospital unit before the MPS assessment the following morning. We used stable isotopic methods and collected vastus lateralis biopsies â¼2 to 3 h apart to assess mixed MPS. MPS was â¼12% higher (P < 0.05) for outpatients than inpatients. Within a subset of participants, we discovered that after instruction to limit activity, outpatients (n = 13) took 800 to 900 steps in the morning to arrive at the unit, seven times more steps than inpatients (n = 12). We concluded that an overnight stay in the hospital as an inpatient is characterized by reduced morning activity and causes a slight but significant reduction in MPS compared with participants studied as outpatients. Researchers should be aware of physical activity status when designing and interpreting MPS results.NEW & NOTEWORTHY The postabsorptive muscle protein synthesis rate is lower in the morning after an overnight inpatient hospital stay compared with an outpatient visit. Although only a minimal amount of steps was conducted by outpatients (â¼900), this was enough to increase postabsorptive muscle protein synthesis rate.
Assuntos
Pacientes Internados , Proteínas Musculares , Humanos , Pacientes Ambulatoriais , Estudos Retrospectivos , Biossíntese de ProteínasRESUMO
Cardiovascular diseases (CVD) are the leading cause of mortality in modernized societies. Arterial stiffening with aging and disease is a key pathological event leading to increased CVD morbidity and mortality. Perivascular adipose tissue (PVAT) is a fat depot not widely studied yet has direct and profound effects on arterial stiffening. Identifying PVAT as a novel therapeutic target to lower arterial stiffness and thereby CVD risk has potentially important clinical ramifications. Thus, herein, we will overview the current preclinical evidence and the associated mechanisms for PVAT to promote arterial stiffness with aging and other disease conditions. We will also discuss viable translational lifestyle and pharmacological interventions for altering PVAT function that may de-stiffen arteries. Last, the translational potential for PVAT as a therapeutic target to lower arterial stiffness and CVD risk for clinical populations will be discussed.
Assuntos
Doenças Cardiovasculares , Rigidez Vascular , Tecido Adiposo/patologia , Envelhecimento , Artérias/patologia , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/patologia , HumanosRESUMO
PURPOSE: To examine the acute influence of caffeine on post-exercise central blood pressures, arterial stiffness, and wave reflection properties. METHODS: In a double-blind randomized placebo-controlled crossover study design, ten middle-aged males (55 ± 5 year) completed two exercise trials after ingestion of caffeine (400 mg) or placebo. Measurements were taken before and 30 min post-ingestion via cuff-based pulse wave analysis (PWA) and carotid-femoral pulse wave velocity (PWV). Participants performed a 40-min cycling bout at 70% HRmax with matched workloads between trials. PWA and PWV were reassessed 30 min post-exercise. RESULTS: Prior to exercise, compared to placebo, caffeine increased brachial systolic blood pressure (bSBP) (+ 12.3 ± 2.4 mmHg; p = 0.004), brachial diastolic blood pressure (bDBP) (+ 7.7 ± 0.9 mmHg; p = 0.011), central systolic blood pressure (cSBP) (+ 11.1 ± 2.1 mmHg; p = 0.005) and central diastolic blood pressure (cDBP) (+ 7.6 ± 1.0 mmHg; p = 0.012). PWV was higher 30 min after pill ingestion (p = 0.021 for time) with a trend for a greater increase in caffeine (p = 0.074 for interaction). bSBP (p = 0.036) and cSBP (p = 0.007) were lower after exercise but remained higher (both p < 0.001) in caffeine compared to placebo. PWV remained higher (p = 0.023) after exercise in caffeine compared to placebo but was not influenced by exercise. At rest, augmentation pressure (AP) and index (AIx) were not influenced by caffeine ingestion. Conversely, AIx was lower (p = 0.009) after exercise in placebo only. CONCLUSION: In healthy and active middle-aged men, pre-exercise caffeine ingestion led to higher central and peripheral systolic blood pressures, PWV and AIx at 30 min post-exercise, indicating an increased left ventricular workload which may have implications for cardiovascular event risk.
Assuntos
Cafeína/administração & dosagem , Exercício Físico/fisiologia , Hemodinâmica/efeitos dos fármacos , Aorta/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Artéria Braquial/efeitos dos fármacos , Artérias Carótidas/efeitos dos fármacos , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Onda de Pulso/métodos , Rigidez Vascular/efeitos dos fármacosRESUMO
Intermuscular adipose tissue (IMAT) is associated with impaired skeletal muscle contractile and metabolic function. Myostatin and downstream signaling proteins such as cyclin-dependent kinase 2 (CDK2) contribute to the regulation of adipose and skeletal muscle mass in cell culture and animals models, but this relationship remains incompletely understood in humans. The purpose of this study was to determine if the infiltration of IMAT was associated with skeletal muscle myostatin and downstream proteins before and after 12 wk of aerobic exercise training (AET) in healthy older women (OW; 69 ± 2 yr), older men (OM; 74 ± 3 yr), and young men (YM; 20 ± 1 yr). We found that the infiltration of IMAT was correlated with myostatin and phosphorylated CDK2 at tyrosine 15 [P-CDK2(Tyr15)]. IMAT infiltration was greater in the older subjects and was associated with lower skeletal muscle function and exercise capacity. After 12 wk of AET, there was no change in body weight. Myostatin and P-CDK2(Tyr15) were both decreased after AET, and the reduction in myostatin was associated with decreased IMAT infiltration. The decrease in myostatin and IMAT occurred concomitantly with increased exercise capacity, skeletal muscle size, and function after AET. These findings demonstrate that the reduction in IMAT infiltration after AET in weight stable individuals was accompanied by improvements in skeletal muscle function and exercise capacity. Moreover, the association between myostatin and IMAT was present in the untrained state and in response to exercise training, strengthening the potential regulatory role of myostatin on IMAT.
Assuntos
Tecido Adiposo/fisiologia , Adiposidade , Exercício Físico/fisiologia , Contração Muscular , Músculo Esquelético/metabolismo , Miostatina/metabolismo , Tecido Adiposo/diagnóstico por imagem , Fatores Etários , Idoso , Ciclismo , Biomarcadores , Biópsia , Quinase 2 Dependente de Ciclina/metabolismo , Teste de Esforço , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Força Muscular , Músculo Esquelético/diagnóstico por imagem , Fosforilação , Comportamento Sedentário , Fatores de Tempo , Adulto JovemRESUMO
The purpose of this investigation was to examine the influence of short-term intense endurance training on cycling performance, along with the acute and chronic signaling responses of skeletal muscle stress and stability markers. Ten recreationally active subjects (25 ± 2 yr, 79 ± 3 kg, 47 ± 2 ml·kg-1·min-1) were studied before and after a 12-day cycling protocol to examine the effects of short-term intense (70-100% VÌo2max) exercise training on resting and exercise-induced regulation of molecular factors related to skeletal muscle cellular stress and protein stability. Skeletal muscle biopsies were taken at rest and 3 h following a 20-km cycle time trial on days 1 and 12 to measure mRNA expression and protein content. Training improved (P < 0.05) cycling performance by 5 ± 1%. Protein oxidation was unaltered on day 12, while resting SAPK/JNK phosphorylation was reduced (P < 0.05), suggesting a reduction in cellular stress. The maintenance in the myocellular environment may be due to synthesis of cytoprotective markers, along with enhanced degradation of damage proteins, as training tended (P < 0.10) to increase resting protein content of manganese superoxide dismutase and heat shock protein 70 (HSP70), while mRNA expression of MuRF-1 was elevated (P < 0.05). Following training (day 12), the acute exercise-induced transcriptional response of TNF-α, NF-κB, MuRF-1, and PGC1α was attenuated (P < 0.05) compared with day 1 Collectively, these data suggest that short-term intense training enhances protein stability, creating a cellular environment capable of resistance to exercise-induced stress, which may be favorable for adaptation.
Assuntos
Exercício Físico/fisiologia , Proteínas Musculares/metabolismo , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Transcriptoma/fisiologia , Adaptação Fisiológica/fisiologia , Adulto , Biomarcadores/metabolismo , Feminino , Regulação da Expressão Gênica/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Músculo Esquelético/citologia , Estresse Oxidativo/fisiologia , Condicionamento Físico Humano/métodos , Ativação Transcricional/fisiologiaRESUMO
Current dogma suggests that aerobic exercise training has minimal effects on skeletal muscle size. We and others have demonstrated that aerobic exercise acutely and chronically alters protein metabolism and induces skeletal muscle hypertrophy. These findings promote an antithesis to the status quo by providing novel perspective on skeletal muscle mass regulation and insight into exercise countermeasures for populations prone to muscle loss.
Assuntos
Exercício Físico/fisiologia , Músculo Esquelético/anatomia & histologia , Adaptação Fisiológica , Envelhecimento/fisiologia , Humanos , Mitocôndrias Musculares/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Treinamento ResistidoRESUMO
We previously reported an increase in skeletal muscle protein synthesis during fasted and fed recovery from nonexhaustive aerobic exercise (Harber et al., 2010). The current study examined skeletal muscle intracellular signaling in the same subjects to further investigate mechanisms of skeletal muscle protein metabolism with and without feeding following aerobic exercise. Eight males (VO2peak: 52 ± 2 ml⻹·kg⻹·min⻹) performed 60-min of cycle ergometry at 72 ± 1% VO2peak on two occasions in a counter-balanced design. Exercise trials differed only in the postexercise nutritional intervention: EX-FED (5 kcal, 0.83 g carbohydrate, 0.37 g protein, 0.03 g fat per kg body weight) and EX-FAST (noncaloric, isovolumic placebo) ingested immediately and one hour after exercise. Muscle biopsies were obtained from the vastus lateralis at rest (on a separate day) and two hours postexercise to assess intracellular signaling via western blotting of p70S6K1, eEF2, 4EBP1, AMPKα and p38 MAPK. p70S6K1 phosphorylation was elevated (p < .05) in EX-FED relative to REST and EX-FAST. eEF2, 4EBP1, AMPKα and p38 MAPK signaling were unaltered at 2 h after exercise independent of feeding status when expressed as the ratio of phosphorylated to total protein normalized to actin. These data demonstrate that feeding after a nonexhaustive bout of aerobic exercise stimulates skeletal muscle p70S6K1 intracellular signaling favorable for promoting protein synthesis which may, as recent literature has suggested, better prepare the muscle for subsequent exercise bouts. These data provide further support into the role of feeding on mechanisms regulating muscle protein metabolism during recovery from aerobic exercise.
Assuntos
Ingestão de Energia/fisiologia , Exercício Físico/fisiologia , Jejum/fisiologia , Proteínas Musculares/metabolismo , Músculo Quadríceps/fisiologia , Descanso/fisiologia , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Ciclismo/fisiologia , Biópsia , Ingestão de Alimentos , Humanos , Masculino , Fator 2 de Elongação de Peptídeos/metabolismo , Fosforilação , Músculo Quadríceps/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Adulto Jovem , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
PURPOSE: The objective of this study was to determine the relationship between aortic stiffening and brachial and central ambulatory blood pressure (AMBP) in a nonclinical sample of middle-aged and older adults (MA/O). We hypothesized aortic stiffness would be positively associated with 24-hr, daytime, and nighttime brachial and central AMBP. METHODS: Fifty-one participants aged ≥50 yr (21 males and 30 females, mean age 63.4 ± 9.0 yr) with a body mass index <35 kg/m 2 who also had a resting brachial blood pressure (BP) <160/100 mmHg with or without BP medications were recruited for this cross-sectional analysis. All participants underwent measures of aortic stiffness (carotid-femoral pulse wave velocity [cfPWV]) and 24-hr AMBP monitoring. Bivariate correlations assessed the relationship between cfPWV, brachial, and central AMBP. Partial correlations were used to independently adjust for traditional cardiovascular disease (CVD) risk factors including age, sex, waist circumference, glucose, and augmentation index normalized to heart rate 75 bpm, a surrogate measure of arterial stiffness, and in a multivariable combined model. RESULTS: Nighttime brachial systolic BP ( r = 0.31) and central systolic BP ( r = 0.30) were correlated with cfPWV in the multivariable combined model ( P ≤ .05). Nighttime brachial pulse pressure and central pulse pressure were correlated with cfPWV after independently adjusting for all CVD risk factors ( P ≤ .05, all) but not when combined in the multivariable model ( P > .05). CONCLUSIONS: Higher nighttime brachial and central AMBP with older age are related, in part, to greater aortic stiffening. Therefore, interventions to lower or prevent aortic stiffening may also lower nighttime BP in MA/O adults to lower CVD risk.
Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea , Ritmo Circadiano , Rigidez Vascular , Humanos , Rigidez Vascular/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Transversais , Monitorização Ambulatorial da Pressão Arterial/métodos , Pressão Sanguínea/fisiologia , Idoso , Ritmo Circadiano/fisiologia , Análise de Onda de Pulso/métodos , Fatores de Risco , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/etiologiaRESUMO
BACKGROUND: A high minute ventilation/rate of carbon dioxide production (VÌE/VÌco2) slope during exercise is prognostic for cardiovascular death. Recent data indicate that adults with either controlled or untreated primary hypertension, but not those with uncontrolled hypertension, exhibit a higher VÌE/VÌco2 slope during exercise. However, the sample sizes were modest. Therefore, we used the Fitness Registry and the Importance of Exercise National Database to determine whether adults with hypertension, particularly those with controlled or untreated hypertension, exhibit higher VÌE/VÌco2 slopes compared with adults without hypertension. METHODS AND RESULTS: Using the Fitness Registry and the Importance of Exercise National Database, we isolated primary hypertension by excluding those with any disease other than hypertension or taking any medications other than antihypertension medications. We also excluded current smokers and those with obesity. The VÌE/VÌco2 slope was determined during a peak cycling exercise test. All data are presented as median [interquartile range]. We compared groups using linear regression adjusted for age, male/female, and body mass index. The characteristics of the entire sample (n=4109) were age, 42 [18] years; 48% women; body mass index, 26 [4] kg/m2. The VÌE/VÌco2 slope did not differ between adults with hypertension (n=1940; 24.7 [3.7]) compared with those without hypertension (n=2169; 24.9 [3.8]) (hypertension versus no hypertension, P=0.31; overall model: R2=0.07, F4,4104=73.0; P<0.001). Further, the VÌE/VÌco2 slope did not differ between adults with medication-controlled hypertension (n=107; 24.4 [3.0]), untreated hypertension (n=1626; 24.8 [3.9]), uncontrolled hypertension (n=207; 24.8 [3.0]), or those without hypertension (n=2169; 24.9 [3.8]) (hypertension subgroup versus no hypertension, P≥0.06; overall model: R2=0.07, F6,4102=49.6, P<0.001). CONCLUSIONS: Primary hypertension is not associated with VÌE/VÌco2 slope in the Fitness Registry and the Importance of Exercise National Database.
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Bases de Dados Factuais , Teste de Esforço , Hipertensão , Sistema de Registros , Humanos , Masculino , Feminino , Adulto , Hipertensão/fisiopatologia , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Pessoa de Meia-Idade , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Estados Unidos/epidemiologia , Aptidão Cardiorrespiratória , Ventilação Pulmonar , Dióxido de Carbono/metabolismo , Pressão Sanguínea/fisiologiaRESUMO
PURPOSE: To determine if individuals chronically (>1 yr) prescribed antihypertensive medications have a normal BP response to peak exercise compared with unmedicated individuals. METHODS: Participants included 2555 adults from the Ball State Adult Fitness Longitudinal Lifestyle STudy cohort who performed a peak treadmill exercise test. Participants were divided into groups by sex and antihypertensive medication status. Individuals prescribed antihypertensive medications for >1 yr were included. Exaggerated and blunted SBP within each group was categorized using the Fitness Registry and the Importance of Exercise: A National Database (FRIEND) and absolute criteria as noted by the American Heart Association. RESULTS: The unmedicated group had a greater prevalence ( P < 0.05) of blunted SBP responses, whereas the medicated group had a higher prevalence ( P < 0.05) of exaggerated SBP responses using both the FRIEND and absolute criteria. Peak SBP was higher ( P < 0.01) in medicated compared with unmedicated participants in the overall cohort when controlling for age and sex, but not after controlling for resting SBP ( P = 0.613), risk factors ( P = 0.104), or cardiorespiratory fitness ( P = 0.191). When men and women were assessed independently, peak SBP remained higher in the medicated women after controlling for age and resting SBP ( P = 0.039), but not for men ( P = 0.311). Individuals on beta-blockers had a higher peak SBP even after controlling for age, sex, risk factors, and cardiorespiratory fitness ( P = 0.022). CONCLUSIONS: Individuals on antihypertensive medications have a higher peak SBP response to exercise. Given the prognostic value of exaggerated peak SBP, control of exercise BP should be considered in routine BP assessment and in the treatment of hypertension.
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Anti-Hipertensivos , Pressão Sanguínea , Exercício Físico , Humanos , Masculino , Anti-Hipertensivos/administração & dosagem , Feminino , Pessoa de Meia-Idade , Pressão Sanguínea/efeitos dos fármacos , Exercício Físico/fisiologia , Adulto , Teste de Esforço , Estudos Longitudinais , Aptidão Cardiorrespiratória , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Fatores Sexuais , IdosoRESUMO
Cardiorespiratory fitness (CRF) is a well-established biomarker that has applications to all adults across the health and disease spectrum. Despite overwhelming evidence supporting the prognostic utility of CRF, it remains vastly underutilized. CRF is optimally measured via cardiopulmonary exercise testing which may not be feasible to implement on a large scale. Therefore, it is prudent to develop ways to accurately estimate CRF that can be applied in clinical and community settings. As such, several prediction equations incorporating non-exercise information that is readily available from routine clinical encounters have been developed that provide an adequate reflection of CRF that could be implemented to raise awareness of the importance of CRF. Further, technological advances in smartphone apps and consumer-grade wearables have demonstrated promise to provide reasonable estimates of CRF that are widely available, which could enhance the utilization of CRF in both clinical and community settings.
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Aptidão Cardiorrespiratória , Teste de Esforço , Consumo de Oxigênio , Humanos , Aniversários e Eventos Especiais , Nível de Saúde , História do Século XXI , Aplicativos Móveis , Valor Preditivo dos TestesRESUMO
INTRODUCTION: Considerable and convincing global data from cohorts across the health spectrum (i.e. apparently healthy to known disease) indicate that cardiorespiratory fitness (CRF) is a major predictor of overall and cardiovascular disease (CVD)-survival, seemingly with greater prognostic resolution compared to other traditional CVD risk factors. Therefore, the assessment of CRF in research and clinical settings is of major importance. AREAS COVERED: In this manuscript, we review the technology of measuring CRF assessed by the 'gold standard,' cardiopulmonary exercise testing (CPET), as well as with various other methods (e.g. estimated metabolic equivalents, 6-minute walk tests, shuttle tests, and non-exercise equations that estimate CRF), all of which provide significant prognostic information for CVD- and all-cause survival. The literature through May 2024 has been cited. EXPERT OPINION: The promotion of physical activity in efforts to improve levels of CRF is needed throughout the world to improve lifespan and, more importantly, healthspan. The routine assessment of CRF should be considered a vital sign that is routinely assessed in clinical practice.
Assuntos
Aptidão Cardiorrespiratória , Doenças Cardiovasculares , Teste de Esforço , Exercício Físico , Aptidão Cardiorrespiratória/fisiologia , Humanos , Teste de Esforço/métodos , Doenças Cardiovasculares/fisiopatologia , Exercício Físico/fisiologia , Prognóstico , Fatores de Risco de Doenças Cardíacas , Teste de Caminhada/métodos , Taxa de SobrevidaRESUMO
Exercise capacity (EC) is an important predictor of survival in the general population and in subjects with cardiopulmonary disease. Despite its relevance, considering the percent-predicted workload (%pWL) given by current equations may overestimate EC in older adults. Therefore, to improve the reporting of EC in clinical practice, our main objective was to develop workload reference equations (pWL) that better reflect the relation between workload and age. Using the Fitness Registry and the Importance of Exercise National Database (FRIEND), we analyzed a reference group of 6,966 apparently healthy participants and 1,060 participants with heart failure who underwent graded treadmill cardiopulmonary exercise testing. For the first group, the mean age was 44 years (18 to 79); 56.5% of participants were males and 15.4% had obesity. Peak oxygen consumption was 11.6 ± 3.0 METs in males and 8.5 ± 2.4 METs in females. After partition analysis, we first developed sex-specific pWL equations to allow comparisons to a healthy weight reference. For males, pWL (METs) = 14.1-0.9×10-3×age2 and 11.5-0.87×10-3×age2 for females. We used those equations as denominators of %pWL, and based on their distribution, we determined thresholds for EC classification, with average EC defined by the range corresponding to 85% to 115%pWL. Compared with %pWL using current equations, the new equations yielded better-calibrated %pWL across different age ranges. We also derived body mass index-adjusted pWL equations that better assessed EC in subjects with heart failure. In conclusion, the novel pWL equations have the potential to impact the report of EC in practice.
Assuntos
Insuficiência Cardíaca , Doença Cardiopulmonar , Feminino , Masculino , Humanos , Idoso , Adulto , Pré-Escolar , Tolerância ao Exercício , Carga de Trabalho , Índice de Massa CorporalRESUMO
INTRODUCTION: We examined if epinephrine in the local anesthetic to help control incision-related bleeding interferes with molecular measurements obtained with the Duchenne-Bergström percutaneous needle biopsy technique for sampling human skeletal muscle. METHODS: Three groups received 2.5-3.0 ml of 1% lidocaine in 2 injections: (1) 0.5-1.0 ml superficially, which varied among the groups according to (i) -Epi; intra- and subcutaneous without epinephrine, (ii) +Epi -Fascia; intra- and subcutaneous with epinephrine, avoiding the fascia, and (iii) +Epi +Fascia; intra- and subcutaneous with epinephrine, directing a small amount (â½0.2 ml) into the fascia area; and (2) â½2.0 ml without epinephrine into the fascia area for all subjects. A muscle biopsy was obtained 5-10 min later for IL-6 and MuRF-1 mRNA levels. RESULTS: IL-6 mRNA levels were low in -Epi and +Epi -Fascia, but â½300-fold higher in +Epi +Fascia. MuRF-1 mRNA levels were similar among the groups. CONCLUSIONS: Lidocaine with epinephrine can confound intramuscular measurements from needle biopsies, but this can be avoided with a careful injection approach.
Assuntos
Anestésicos Locais/efeitos adversos , Epinefrina/efeitos adversos , Lidocaína/efeitos adversos , Músculo Esquelético/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Vasoconstritores/efeitos adversos , Adulto , Anestésicos Locais/administração & dosagem , Biópsia por Agulha , Epinefrina/administração & dosagem , Humanos , Injeções/classificação , Interleucina-6/antagonistas & inibidores , Interleucina-6/biossíntese , Interleucina-6/metabolismo , Lidocaína/administração & dosagem , Masculino , Proteínas Musculares/antagonistas & inibidores , Proteínas Musculares/biossíntese , Proteínas Musculares/genética , Músculo Esquelético/patologia , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/biossíntese , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/biossíntese , Ubiquitina-Proteína Ligases/genética , Vasoconstritores/administração & dosagem , Adulto JovemRESUMO
BACKGROUND: Exercise and nutritional interventions have been examined independently as countermeasures to offset the loss of skeletal muscle mass with unloading, yet a protocol to completely preserve the soleus has not been identified. Little is known regarding the combined effect of exercise and nutrition on factors regulating skeletal muscle growth. The purpose of this investigation was to evaluate the influence of amino acid (AA) infusion on myogenic (MRF-4, MyoD, and Myogenin), proteolytic (MuRF-1, Atrogin-1, FOXO3A, Calpain-1, Calpain-2, Caspase-3, Cathepsin L1), and cytokine (IL-6, IL-8, and IL-15) mRNA transcripts in two skeletal muscles that respond distinctly to microgravity unloading. METHODS: Muscle biopsies were obtained from the vastus lateralis (VL) and soleus of eight male subjects prior to and after 4 h of AA infusion for analysis of mRNA expression. All subjects performed a standardized exercise bout (45-min treadmill run) 24 h prior to the AA infusion. RESULTS: In the VL, proteolytic factors MuRF-1 and FOXO3A were reduced (44 +/- 9 and 28 +/- 6%, respectively) in response toAA infusion. In the soleus, mRNA transcripts of myogenic factor MRF-4 (91 +/- 36%) and cytokines IL-6, IL-8, and IL-15 were elevated while the proteolytic marker FOXO3A mRNA was reduced by 19 +/- 9%. DISCUSSION: These data suggest that the expression of genes related to skeletal muscle remodeling is altered during acute AA infusion 24 h post-exercise. It appears that increased amino acid availability in concert with exercise may create an intramuscular environment favorable for the prevention of muscle atrophy associated with unloading, which may be particularly beneficial for the soleus.
Assuntos
Aminoácidos/farmacologia , Cisteína Endopeptidases/genética , Citocinas/genética , Expressão Gênica/efeitos dos fármacos , Proteínas Musculares/genética , Músculo Esquelético/metabolismo , Adulto , Cisteína Endopeptidases/efeitos dos fármacos , Cisteína Endopeptidases/metabolismo , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Exercício Físico/fisiologia , Humanos , Masculino , Proteínas Musculares/efeitos dos fármacos , Proteínas Musculares/metabolismo , Músculo Esquelético/efeitos dos fármacos , Fatores de Regulação Miogênica/genética , Fatores de Regulação Miogênica/metabolismo , Músculo Quadríceps/efeitos dos fármacos , Músculo Quadríceps/metabolismo , RNA Mensageiro/metabolismo , Adulto JovemRESUMO
PURPOSE: To determine the acute effects of a mitochondrial targeting antioxidant (MitoQ) on the metabolic response during exercise. METHODS: Nine (n = 9) physically inactive females (age 47 ± 22 years) performed two trials (Placebo and MitoQ) in a double-blind randomized cross-over design. In both trials, participants performed an exercise protocol consisting of 3-min stages at submaximal workloads followed by a ramp protocol to volitional exhaustion. Participants received either Placebo or MitoQ (80 mg) 1 h prior to exercise. Indirect calorimetry and cardiovascular measurements were collected throughout the duration of the exercise bout. RESULTS: Submaximal metabolic and cardiovascular variables were not different between trials (p > 0.05). VO2max was higher (p = 0.03) during Placebo (23.5 ± 5.7 mL kg min-1 ) compared to MitoQ (21.0 ± 6.6 mL kg min-1 ). Maximal ventilation was also higher (p = 0.02) in Placebo (82.4 ± 17.7 L/min) compared to MitoQ (75.0 ± 16.8 L/min). Maximal cardiovascular variables and blood lactate were not different between trials (p > 0.05). CONCLUSION: An acute dose of MitoQ blunted VO2max , which was primarily mediated by impairment of ventilatory function. These data suggest that the acute accumulation of exercise-induced mitochondrial reactive oxygen species (mtROS) are necessary for maximal aerobic capacity. Further research is warranted on mtROS-antioxidant cell signaling cascades, and how they relate to mitochondrial function during exercise.