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BACKGROUND: Congenital Generalized Lipodystrophy (CGL) is an ultra-rare disease characterized by metabolic disorders. However, the evaluation of functional exercise capacity, cardiovascular (CV) response to exercise, and peripheral arterial disease (PAD) in CGL is scarce. Here we evaluated the performance and CV response to exercise and their association with PAD in CGL compared to healthy individuals. METHODS: Twelve CGL and 12 healthy subjects matched for age and gender were included. Functional exercise capacity, CV response, and PAD were measured using the six-minute walk test (6MWT) and ankle-brachial index (ABI), respectively. RESULTS: At baseline, CGL subjects showed reduced predicted walked distance (6MWD) (p = 0.009) and increased heart rate (HR), systolic (SBP), and diastolic (DBP) pressures compared to healthy subjects (p < 0.05). Most CGL subjects presented normal ABI values (1.0 ≤ ABI ≤ 1.4). Only 25% (n = 3) had ABI ≤ 0.9. CGL subjects did not present changes in ABI and blood pressure 12 months after metreleptin (MLP) replacement, but they walked a greater 6MWD than baseline (p = 0.04). Further, 6MWD and right ABI measurements were positively correlated in CGL subjects (p = 0.03). Right ABI negatively correlated with glucose, triglycerides, and VLDL-c (p < 0.05). CONCLUSIONS: We observed that CGL subjects had lower functional exercise capacity and higher cardiovascular effort for similar performance of 6MWT, suggesting that strategies for decreasing exercise effort in this population should be essential. Furthermore, better physical performance was associated with high ABI in CGL. Additional studies are needed to clarify leptin's role in preserving functional exercise capacity in CGL.

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Introduction: Despite growing evidence regarding the benefits of resistance training in hypertension, the large and abrupt rise of systolic blood pressure (SBP) observed during resistance exercise execution has resulted in concern about its safety. However, the manipulation of the resistance training protocol (RTP) organization, maintaining the work to rest ratio equated between protocols (W:R-equated), may reduce the SBP increase. Purpose: To compare cardiovascular responses during two W:R-equated RTPs (3 × 15:88 s vs. 9 × 5:22 s - sets × reps: rest between sets) performed in exercises for the lower and upper limbs. Methods: Twelve medicated hypertensives (48 ± 8 years) randomly performed two RTPs in the bilateral leg extension (BLE) and unilateral elbow flexion (UEF) exercises at 50% 1RM. Increases (Δ) of SBP, heart rate (HR) and rate pressure product (RPP) during the exercises were measured by photoplethysmography. Results: In both BLE and UEF exercises, Δ SBP was significantly greater during 3 × 15:88 s than 9 × 5:22 s (peak values: BLE = + 84 ± 39 vs. + 67 ± 20 mm Hg, and UEF = + 46 ± 25 vs. + 37 ± 18 mm Hg, respectively, both p < 0.05). ΔHR and ΔRPP were significantly higher in the 3 × 15:88 s than 9 × 5:22 s in BLE (peak values + 45 ± 17 vs. + 30 ± 8 bpm, and + 15,559 ± 5570 vs. + 10,483 ± 2614 mm Hg. bpm). Conclusion: In medicated hypertensives, a RTP combining more sets with less repetitions per set and shorter rest intervals between sets (i.e., 9 × 5:22 s) produced a smaller increase in cardiovascular load (ΔSBP, ΔHR and ΔRPP) during its execution than a protocol with fewer longer sets (i.e., 3 × 15:88 s).

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PURPOSE: To investigate the effect of heat stress on postexercise hypotension. METHODS: Seven untrained men, aged 21-33 years, performed two cycling bouts at 60% of oxygen uptake reserve expending 300 kcal in environmental temperatures of 21 °C (TEMP) and 35 °C (HOT) in a randomized, counter-balanced order. Physiological responses were monitored for 10-min before and 60-min after each exercise bout, and after a non-exercise control session (CON). Blood pressure (BP) also was measured during the subsequent 21-h recovery period. RESULTS: Compared to CON, systolic, and diastolic BPs were significantly reduced in HOT (Δ = - 8.3 ± 1.6 and - 9.7 ± 1.4 mmHg, P < 0.01) and TEMP (Δ = - 4.9 ± 2.1 and - 4.5 ± 0.9 mmHg, P < 0.05) during the first 60 min of postexercise recovery. Compared to TEMP, rectal temperature was 0.6 °C higher (P = 0.001), mean skin temperature was 1.8 °C higher (P = 0.013), and plasma volume (PV) was 2.6 percentage points lower (P = 0.005) in HOT. During the subsequent 21-h recovery period systolic BP was 4.2 mmHg lower in HOT compared to CON (P = 0.016) and 2.5 mmHg lower in HOT compared to TEMP (P = 0.039). CONCLUSION: Exercise in the heat increases the hypotensive effects of exercise for at least 22 h in untrained men with elevated blood pressure. Our findings indicate that augmented core and skin temperatures and decreased PV are the main hemodynamic mechanisms underlying a reduction in BP after exercise performed under heat stress.

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We hypothesized that dorsomedial hypothalamus (DMH) modulates autonomic and neuroendocrine responses in rats at rest and when subjected to restraint stress (RS). Male Wistar rats were used, and guide cannulas were bilaterally implanted in the DMH for microinjection of vehicle or the nonspecific synaptic blocker CoCl2 (1 mM/100 nl). A polyethylene catheter was inserted into the femoral artery for the recording of arterial pressure and heart rate (HR). Tail temperature was measured using a thermal camera. The session of RS started 10 min after DMH treatment with vehicle or CoCl2. Under home-cage condition, the pretreatment of DMH with CoCl2 increased baseline blood pressure (BP), and heart rate (HR) without affecting the tail temperature. In addition, it decreased plasma vasopressin levels without affecting plasma corticosterone and oxytocin contents. When rats pretreated with CoCl2 were exposed to RS, the RS-evoked cardiovascular were similar to those observed in vehicle-treated animals; however, because cobalt pretreatment of the DMH increased baseline BP and HR values, and the RS-evoked cardiovascular responses did not exceed those observed in vehicle-treated animals, suggesting a possible celling limit, the possibility that DMH is involved in the modulation of RS-evoked cardiovascular responses cannot be certainly excluded. Nonetheless, the pretreatment of DMH with CoCl2 blocked the reduction in tail temperature caused by RS. The DMH pretreatment with CoCl2 did not modify the RS-evoked increase in plasma corticosterone and oxytocin contents. In conclusion, the present data suggest the involvement of DMH in the maintenance of BP, HR, and vasopressin release under the rest conditions at the home-cage. Furthermore, indicate that DMH is an important thermoregulatory center during exposure to RS, regulating tail artery vasoconstriction.

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The aim of this study was to analyze blood lactate concentration (LAC), heart rate (HR), and rating perceived exertion (RPE) during and after shorter and longer duration CrossFit® sessions. Nine men (27.7 ± 3.2 years; 11.3 ± 4.6% body fat percentage and training experience: 41.1 ± 19.6 months) randomly performed two CrossFit® sessions (shorter: ~4 min and longer: 17 min) with a 7-day interval between them. The response of LAC and HR were measured pre, during, immediately after, and 10, 20, and 30 min after the sessions. RPE was measured pre and immediately after sessions. Lactate levels were higher during the recovery of the shorter session as compared with the longer session (shorter: 15.9 ± 2.2 mmol/L/min, longer: 12.6 ± 2.6 mmol/L/min; p = 0.019). There were no significant differences between protocols on HR during (shorter: 176 ± 6 bpm or 91 ± 4% HRmax, longer: 174 ± 3 bpm or 90 ± 3% HRmax, p = 0.387). The LAC was significantly higher throughout the recovery period for both training sessions as compared to pre-exercise. The RPE was increased immediately after both sessions as compared to pre-exercise, while there was no significant difference between them (shorter: 8.7 ± 0.9, longer: 9.6 ± 0.5; p = 0.360). These results demonstrated that both shorter and longer sessions induced elevated cardiovascular responses which met the recommendations for gains in cardiovascular fitness. In addition, both training sessions had a high metabolic and perceptual response, which may not be suitable if performed on consecutive days.

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Previously, we reported that microinjection of L-proline (L-Pro) into the paraventricular nucleus of the hypothalamus (PVN) caused vasopressin-mediated pressor responses in unanesthetized rats. In the present study, we report on the central mechanisms involved in the mediation of the cardiovascular effects caused by the microinjection of L-Pro into the PVN. Microinjection of increasing doses of L-Pro (3-100nmol/100nL) into the PVN caused dose-related pressor and bradycardic responses. No cardiovascular responses were observed after the microinjection of equimolar doses (33nmol/100nL) of its isomer D-Proline (D-Pro) or Mannitol. The PVN pretreatment with either a selective non-NMDA (NBQX) or selective NMDA (LY235959 or DL-AP7) glutamate receptor antagonists blocked the cardiovascular response to L-Pro (33nmol/100nL). The dose-effect curve for the pretreatment with increasing doses of LY235959 was located at the left in relation to the curves for NBQX and DL-AP7, showing that LY235959 is more potent than NBQX, which is more potent than DL-AP7 in inhibiting the cardiovascular response to L-Pro. The cardiovascular response to the microinjection of L-Pro into the PVN was not affected by local pretreatment with Nω-Propyl-l-arginine (N-Propyl), a selective inhibitor of the neuronal nitric oxide synthase (nNOS), suggesting that NO does not mediate the responses to L-Pro in the PVN. In conclusion, the results suggest that ionotropic receptors in the PVN, blocked by both NMDA and non-NMDA receptor antagonists, mediate the pressor response to L-Pro that results from activation of PVN vasopressinergic magnocellular neurons and vasopressin release into the systemic circulation.

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The purpose of this study was to compare the effect of a combined exercise session performed at different periods of the day on the 24h blood pressure (BP) response. Anaerobic threshold (AT) and 12 repetition maximum (12RM) tests were evaluated in nine Brazilian jiu-jitsu athletes (male) (22±3.7 y; 176±5.0 cm; 73.4±9.7 kg; 6.8±2.1 % body fat). Four experimental sessions were performed: resistance exercise followed by aerobic exercise [Morning (MornS) and Afternoon (AfternS)] and Control (C) [Morning and Afternoon]. The morning sessions were conducted at 09:00 a.m. and the afternoon sessions were conducted at 3:00 p.m. The resistance exercise consisted of three sets at 90% of a 12RM for six resistance exercises. The aerobic exercise consisted of 15min at 90% of the AT. Blood pressure (BP) was measured before, during and 1h (Microlife(r) BP3A1C) after the performance of exercises in laboratory, and then during daily activities for the succeeding 23h by ambulatory BP monitoring (Dyna-MAPA(r)). Analysis of the area under the curve (AUC) indicated significant reductions in blood pressure parameters at various time points during the 24h monitoring period. For systolic BP (SBP), significantly lower values were shown following the morning session versus the control (MornS: 1756.2±100.8 vs. C: 1818.2±84.3 mmHg*15h; p < .05) and total-24h (MornS: 2695.8±143.3 vs. C: 2784.1±143.2 mmHg*24h; p < .05). The total-24h mean BP (MAP) was also significantly lower following the morning session versus the control (MornS: 2015.7±121.2 vs. C: 2087.3±153.8 mmHg*24h; p < .05). There were significant differences in the sleeping AUC of SBP (AfternS: 883.6±27.0 vs. C: 965.2±67.9 mmHg*9h; p < .05), diastolic BP (DBP) (AfternS: 481.4±30.9 vs. MornS: 552.9±34.2 and C: 562.1±52.3 mmHg*9h; p < .01) and MBP (AfternS: 651.9±22.4 vs. MornS: 708.7±43.1 and C: 726.9±64.7 mmHg*9h; p < .01)...

O objetivo deste estudo foi comparar o efeito de uma sessão combinada de exercício realizada em diferentes períodos do dia, sobre as respostas de pressão arterial (PA) durante 24h. Limiar anaeróbio (LA) e teste de 12 repetições máximas (12RM) foram avaliados em nove atletas (masculinos) de jiu-jitsu (22,0±3,7 anos; 176,0±5,0 cm; 73,4±9,7 kg; 6,8±2,1 %gordura). Quatro sessões experimentais foram realizadas: exercício resistido + exercício aeróbio [manhã (ManhaE) e tarde (TardeE)] e sessão controle (C) [manhã e tarde]. A sessão da manhã foi realizada 09:00h e a sessão da tarde foi realizada ás 15:00h. O exercício resistido consistiu em três séries a 90% de 12RM em seis exercícios. O exercício aeróbio consistiu em 15min a 90% do LA. PA foi mensurada antes, durante e 1h (Microlife(r) BP3A1C) após a realização dos exercícios em laboratório e 23h durante as atividades diárias com a monitorização ambulatorial da PA (Dyna-MAPA(r)). Ao analisar os valores da área abaixo da curva (AAC) indicaram reduções significativas nos parâmetros de pressão arterial em vários pontos de tempo durante o período de acompanhamento de 24 horas. Para a PA sistólica (PAS), observaram-se valores significativamente mais baixos após a sessão realizada pela manha em comparação a sessão controle na vigília (ManhaE: 1756,2±100,8 vs. C: 1818,2±84,3 mmHg*15h; p< 0,05) e 24h-total (ManhaE: 2695,8±143,3 vs. C: 2784,1±143,2 mmHg*24h; p< 0,05). Nas 24h-total também ocorreu diferença na PA média (PAM) (ManhaE: 2015,7±121,2 vs. C: 2087,3±153,8 mmHg*24h; p< 0,05). Houve uma diferença significativa na AAC no período de sono na PAS (TardeE: 883,6±27,0 vs. C: 965,2±67,9 mmHg*9h; p < 0,05), PA diastólica (PAD) (TardeE: 481,4±30,9 vs. ManhaE: 552,9±34,2 e C: 562,1±52,3 mmHg*9h; p< 0,01) e PAM (TardeE: 651,9±22,4 vs. ManhaE: 708,7±43,1 e C: 726,9±64,7 mmHg*9h; p< 0,01)...

El objetivo de estudio fue comparar el efecto de una sesión combinada de ejercicio realizada en diferentes períodos del día, sobre las respuestas de presión arterial (PA) durante 24h. Umbral anaeróbico (Uan) y test de 12 repeticiones máximas (12RM). Fueron evaluados nueve atletas (hombres) de jiu-jitsu (22,0±3,7 años; 176,0±5,0 cm; 73,4±9,7 kg; 6,8±2,1% grasa). Cuatro sesiones de test fueron realizadas: ejercicio resistido + ejercicio aeróbico [mañana (MañaE) y tarde (tardE)] y sesión control (C) [mañana y tarde]. La sesión matinal ocurrió las 9.00 y la sesión vespertina ocurrió las 15.00. El ejercicios resistidos consistió en tres series a 90% de 12 RM em seis ejercicios. El ejercicio aeróbico consistió en 15 minutos a 90% de LA. La presión arterial (PA) fue medida antes, durante y 1 hora tras la realización de los ejercicios en laboratorio (Microlife(r) BP3A1C) y 23 horas durante las actividades diarias con el monitoreo ambulatorio de la PA (Dyna-MAPA(r)). Mediante el análisis del área bajo la curva (ABC) mostraron reducciones significativas en los parámetros de PA en varios puntos de tiempo durante el período de seguimiento de 24 horas. Para la PA sistólica (PAS), hubo valores significativamente más bajos después de las sesiones de vigilia (MañaE: 1756,2±100,8 vs. C: 1818,2±84,3 mmHg*15h; p< 0,05) y 24hs-total (MañaE: 2695,8±143,3 vs. C: 2784,1±143,2 mmHg*24h; p< 0,05). En las 24hs-total también ocurrió diferencia en la PA media (PAM) (MañaE: 2015,7±121,2 vs. C: 2087,3±153,8 mmHg*24h; p< 0,05). En durante el sueño ocurrieron alteraciones en el ABC de la PA PAS (tardE: 883,6±27,0 vs. C: 965,2±67,9 mmHg*9h; p< 0,05), PA diastólica (PAD) (tardE: 481,4±30,9 vs. MañaE: 552,9±34,2 y C: 562,1±52,3 mmHg*9h; p< 0,01) y PA media (tardE: 651,9±22,4 vs. RAM: 708,7±43,1 y C: 726,9±64,7 mmHg*9h; p< 0,01)...

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BACKGROUND: Arterial hypertension is a serious health problem affecting mainly the elderly population. Recent studies have considered both aerobic and resistance exercises as a non-pharmacological aid for arterial hypertension treatment. However, the cardiovascular responses of the elderly to isometric resistance exercise (eg, isometric handgrip [IHG]) have not yet been documented. OBJECTIVE: The purpose of this study was to investigate cardiovascular responses to different intensities of isometric exercise, as well as the occurrence of post-isometric exercise hypotension in hypertensive elderly people under antihypertensive medication treatment. PATIENTS AND METHODS: Twelve women volunteered to participate in the study after a maximal voluntary contraction test (MVC) and standardization of the intervention workload consisting of two sessions of IHG exercise performed in four sets of five contractions of a 10-second duration. Sessions were performed both at 30% of the MVC and 50% of the MVC, using a unilateral IHG protocol. Both intensities were compared with a control session without exercise. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) at rest (R), during peak exercise (PE), and after 5, 10, 15, 30, 45, and 60 minutes of post-exercise recovery were evaluated. RESULTS: No significant changes were observed after isometric exercise corresponding to 30% MVC for either SBP (R: 121 ± 10; PE: 127 ± 14; 5 min: 125 ± 13; 10 min: 123 ± 12; 15 min: 122 ± 11; 30 min: 124 ± 11; 45 min: 124 ± 10; 60 min: 121 ± 10 mmHg) or DBP (R: 74 ± 9; PE: 76 ± 6; 5 min: 74 ± 5; 10 min: 72 ± 8; 15 min: 72 ± 5; 30 min: 72 ± 8; 45 min: 73 ± 6; 60 min: 75 ± 7 mmHg). Similarly, the 50% MVC did not promote post-isometric exercise hypotension for either SBP (R: 120 ± 7; PE: 125 ± 11; 5 min: 120 ± 9; 10 min: 122 ± 9; 15 min: 121 ± 11; 30 min: 121 ± 9; 45 min: 121 ± 9; 60 min: 120 ± 7 mmHg) or DBP (R: 72 ± 8; PE: 78 ± 7; 5 min: 72 ± 7; 10 min: 72 ± 8; 15 min: 71 ± 7; 30 min: 72 ± 8; 45 min: 75 ± 10; 60 min: 75 ± 7 mmHg). CONCLUSION: Our data reveal that cardiovascular overload or post-exercise hypotension did not occur in elderly women with controlled hypertension when they undertook an IHG session. Thus this type of resistance exercise, with mild to moderate intensity, with short time of contraction appears to be safe for this population.

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Metabolic syndrome (MetS) is a cluster of risk factors in individuals with high risk of diabetes and heart disease. Resistance training (RT) has been proposed to be a safe, effective and worthwhile method for the prevention and treatment of metabolic and cardiovascular diseases. However, no study has analysed the acute response of blood pressure (BP) and autonomic control of heart rate (HR) after a RT session in female patients with MetS. The aim of the present study was to analyse the response of laboratory assessed and ambulatory BP and cardiac autonomic modulation after a RT session in women with MetS. Nine women without MetS (35.0 ± 6.7 years) and 10 women with MetS (34.1 ± 9.4 years) completed one experimental exercise session and a control session. Laboratory BP, heart rate variability (HRV) and ambulatory BP of each subject were measured at rest, over 60 min, and for 24 h after the end of the sessions, respectively. There was a significant reduction in systolic blood pressure (SBP), night time diastolic blood pressure (DBP) and mean blood pressure (MBP) only for women with MetS, for all periods after the RT session when compared with the control session (P<0.05). Significantly lower laboratory values of SBP and DBP (10, 30 and 40 min postexercise) and MBP (10, 40 and 50 min postexercise) were observed in women with MetS (P<0.05). Patients with MetS exhibited significant lower basal HRV and a lower autonomic responsiveness during the 60 min of acute recovery. These results confirmed that an acute session of resistance exercise induced a lower BP during day time and sleeping hours in women with MetS that may offer a cardio-protective effect. Women with MetS exhibited an impaired autonomic modulation at rest and a lower acute autonomic responsiveness to a RT session. The dissociation between BP and HRV responses suggests that other factors than autonomic control could be involved in the hypotensive effect of a RT session in MetS patients.

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The aim of the present study was to investigate the role of the lateral hypothalamus (LH) and its local glutamatergic neurotransmission in the cardiovascular adjustments observed when rats are submitted to acute restraint stress. Bilateral microinjection of the nonspecific synaptic inhibitor CoCl2 (0.1 nmol in 100 nL) into the LH enhanced the heart rate (HR) increase evoked by restraint stress without affecting the blood pressure increase. Local microinjection of the selective N-methyl-d-aspartate (NMDA) glutamate receptor antagonist LY235959 (2 nmol in 100 nL) into the LH caused effects that were similar to those of CoCl2 . No changes were observed in the restraint-related cardiovascular response after a local microinjection of the selective non-NMDA glutamatergic receptor antagonist NBQX (2 nmol in 100 nL) into the LH. Intravenous administration of the muscarinic cholinergic receptor antagonist homatropine methyl bromide (0.2 mg/kg), a quaternary ammonium drug that does not cross the blood-brain barrier, abolished the changes in cardiovascular responses to restraint stress following LH treatment with LY235959. In summary, our findings show that the LH plays an inhibitory role on the HR increase evoked by restraint stress. Present results also indicate that local NMDA glutamate receptors, through facilitation of cardiac parasympathetic activity, mediate the LH inhibitory influence on the cardiac response to acute restraint stress.

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BACKGROUND: The aim of this study was to compare post-exercise hypotension after acute sessions of water-walking and land-walking in healthy trained and untrained women. METHODS: Twenty-three untrained (n = 12) and trained (n = 11) normotensive women performed two walking sessions in water and on land at 40% of peak VO(2) for 45 minutes. Systolic and diastolic blood pressure and mean arterial pressure were measured 15, 30, 45, and 60 minutes after the exercise sessions. RESULTS: No differences were found between the groups for age and anthropometric parameters, but peak VO(2) for the trained women (45 ± 8 mL/kg/minute) was higher than for the untrained women (31 ± 3 mL/kg/minute). No differences were found between the groups with regard to systolic and diastolic blood pressure and mean arterial pressure after water immersion. The heart rate in the trained group (62 ± 3 beats per minute [bpm]) was significantly lower (P < 0.05) than in the untrained group (72 ± 4 bpm) on land, and after water immersion, this difference disappeared (58 ± 5 bpm in the trained women and 66 ± 5 bpm in the untrained women). Sixty minutes after water-walking, systolic blood pressure (108 ± 8 mmHg vs 97 ± 3 mmHg), diastolic blood pressure (69 ± 5 mmHg vs 62 ± 5 mmHg), and mean arterial pressure (82 ± 6 mmHg vs 74 ± 4 mmHg) decreased significantly with rest in the untrained group, and no differences were found after land-walking. In the trained group, significant (P < 0.05) differences were found only for systolic blood pressure (110 ± 9 mmHg vs 100 ± 9 mmHg) after 60 minutes of water-walking; decreases in systolic blood pressure were found after 45 minutes (99 ± 7 mmHg) and 60 minutes (99 ± 6 mmHg) compared with rest (107 ± 5 mmHg) after land-walking. CONCLUSION: Single water-walking and land-walking sessions induced important hypotension following exercise. Additionally, walking performed in chest-deep water has a better effect on exercise-induced hypotension in untrained healthy women than walking at a similar intensity on land.

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En esta investigación se midió la respuesta cardiovascular al estrés, autoeficacia computacional y la percepción de dificultad de la tarea, en una muestra de 115 estudiantes de pregrado de la Universidad Simón Bolívar. Los resultados evidencian que en cuanto a los parámetros fisiológicos cardiovasculares, hubo elevación en la presión arterial y la frecuencia cardíaca en ambas versiones del test de stroop (clásico y computarizado). En general, la percepción de la dificultad de la tarea en estos sujetos fue más elevada ante el stroop clásico. Finalmente, en relación con la autoeficacia computacional los sujetos presentan valores altos, lo cual indica una percepción de habilidades para trabajar frente a un computador. Estos resultados representan una contribución importante, pues están indicando la relación de las variables cognitivas y las respuestas fisiológicas del estudiante universitario ante situaciones demandantes o difíciles. De esta manera, las situaciones vividas en el ambiente académico pueden tener un impacto relevante en los estados de salud, y debemos tomar en consideración estos aspectos para el beneficio integral del estudiante

In this investigation of the Cardiovascular Response to Stress, Perceived Task Difficulty and physiological responding were measured. The study used a sample of 115 undergraduate students of a Simon Bolivar University. Results show that a great elevation of heart rate and blood pressure was observed during exposure to the two versions of the Stroop Test (classical and computerized). In general, ratings of perceived difficulty of the Stroop task were higher in response to the Classical administration. Finally, subjects rated their Computer Self-Efficacy as high, indicating confidence and comfort working with computers. These results represent an important contribution that illustrate the relation of cognitive factors to physiological responses during cognitively demanding or difficult situations. In terms of the practical implications of these findings, situations experienced in academic environments can have a prominent impact in cardiovascular responding, and thus, health. As such, it is indicating that the medium of academic assessment might be an appropriate target for change in some settings for the benefit of the Student

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INTRODUÇÃO: O exercício com pesos é atualmente recomendado para diferentes grupos de indivíduos. Seu principal objetivo é o aumento na força muscular, mas podem ocorrer outros resultados , como a redução na pressão arterial (PA) de repouso. Contudo, é pouco abordada a relação entre prescrição do treinamento com pesos, aumento da força e comportamento da PA de repouso em humanos. OBJETIVO: Analisar a PA após uma sessão aguda de exercícios com pesos e após um período de treinamento com pesos, em indivíduos normotensos e hipertensos, em estudos publicados na literatura internacional. MÉTODOS: As referências foram selecionadas de três formas distintas: 1) para compor as sugestões de treinamento de pesos foi utilizado um estudo meta-analítico e um posicionamento oficial de uma reconhecida entidade de pesquisa; 2) para os dados do exercício com pesos e PA de repouso nos momentos pós-exercício, foram pesquisados estudos na base Medline publicados em inglês que acompanharam a PA por pelo menos 60 min; 3) as referências sobre treinamento com pesos em longo prazo e PA de repouso foram resgatadas do último estudo meta-analítico sobre o tema, adicionadas dos experimentos publicados até julho de 2008. RESULTADOS: Após analisar as referências, a prescrição do treinamento com pesos, na maioria dos estudos, seguiu sugestões atuais. Porém, somente em poucos estudos a PA de repouso foi reduzida, tanto em normotensos quanto em hipertensos. CONCLUSÕES: Mesmo com certa variação na prescrição, o treinamento com pesos parece ser suficiente para aumentar a força muscular. Contudo, ainda faltam pesquisas para inferir sobre sua relação com a PA de repouso de normotensos e hipertensos.

INTRODUCTION: Weight training is currently recommended to different groups of individuals. Its main objective is increase in muscular strength, but other results may occur, such as blood pressure (BP) at rest reduction. However, the relationship among weight training prescription, increase in strength and BP behavior at rest in humans is little approached. AIM: To analyze BP after an acute session of weight exercises and after a weight training period in normotensive and hypertensive individuals, in studies published in the international literature. METHODS: References were selected in three distinct ways: 1) in order to compose the weight training suggestions, a meta-analytical and an official positioning of a recognized research entity was used; 2) for the weight exercise and BP at rest data at the post-exercise moments, studies from the Medline basis published in English which followed BP for at least 60 min were researched; 3) references on long term-weight training and BP at rest were retrieved from the last metaanalytical study on the topic, added to the experiments published until July, 2008. RESULTS: After analyzing the references, prescription of weight training in most of the studies followed current recommendations. Nevertheless, only in few studies BP at rest was reduced, both in normotensive and hypertensive subjects. CONCLUSIONS: Despite certain variation in prescription, weight training seems to be efficient in increasing muscular strength. However, further research is still needed in order to infer on its correlation with BP at rest in normotensive and hypertensive subjects.

Assuntos

RESUMO

La región anteroventral del tercer ventrículo (AV3V) es capaz de detectar la concentración sanguínea de NaCl y ajustar la función cardiovascular y renal en respuesta a la composición hidroelectrolítica del líquido extracelular. La microinyección de NaCl hipertónico en esta área cerebral induce un incremento de la actividad simpática que aumenta de la presión arterial; la frecuencia cardíaca y la función renal. Estos cambios pueden ser modulados por la administración central de antagonistas de receptores 5HT2 de serotonina y bloqueadores de los receptores AT1 de angiotensina o por la administración periférica de antagonistas alfa y beta de los receptores adrenérgicos. El papel de las endotelinas cerebrales y del factor natriurético auricular (FNA) en esta región cerebral no ha sido estudiado. Se evaluó la participación de los receptores para endotelinas cerebrales y del FNA en la respuesta cardiovascular al NaCl hipertónico 1,5 M (2myL) administrado en la región AV3V de ratas anestesiadas. La microinyección de NaCl 1,5 M en la región AV3V de ratas normotensas produjo un incremento de la presión arterial media en un máximo de 17,9 ± 2,2 mm de Hg (p<0,01). La microinyección previa de FNA a una dosis 5myg/2myL no alteró la presión arterial media (PAM) ni el efecto en la PAM inducidos por la microinyección de NaCl 1,5 M en AV3V. La administración previa del antagonista no selectivo de los receptores de endotelinas PD-142893 (3myg/2myL) no alteró la PAM basal pero redujo en 8,52 ± 1,20 mm de Hg (47,6%) el incremento de la presión arterial media inducido por el NaCl 1,5 M (p<0,01). Los resultados indican un papel modulador de las endotelinas en la respuesta cardiovascular al NaCl 1,5 M administrado en la región AV3V y ausencia de la participación del FNA en la respuesta cardiovascular simpática evocada por el NaCl.

Third ventricle anteroventral area (AV3V) is sensitive to changes in NaCl concentration and able to modify blood pressure and renal function in response to NaCl concentration. Hypertonic NaCl microinjections in AV3V induce a sympathetic cardiovascular response which increases blood pressure and heart rate; these changes can be modulated by central administration of 5HT2 and AT1 receptor blockers, and also by peripheral administration of alpha and beta adrenergic receptor antagonists. Influence of endothelin receptors (ETR) and atrial natriuretic factor (ANF) on sensitivity to NaCl has not been explored. Hypertonic 1,5 M NaCl (2 muL volume) microinjections in AV3V of normotensive anesthetized rats increased mean arterial blood pressure by 17,9 ± 2.2 mm Hg (p<0.01). ANF microinjections (5mug/2muL) in AV3V neither changed mean arterial blood pressure nor altered the hypertensive response to NaCl 1,5 M microinjection. Microinjection of PD 142893 into AV3V a non selective endothelin antagonist (3mug/2muL) did not modify basal blood pressure but reduced by 47,6% (p<0,01) the hypertensive response to 1,5 M NaCl injection. These results indicates a possible modulator effect of endothelin receptors in the NaCl centrally- evocated cardiovascular response to hypertonic NaCl injections in AV3V. Acute microinjection of ANF in this brain area seems not to be involved in the NaCl-evoked sympathetic cardiovascular response.