-A high-salt diet can lead to hydromineral imbalance and increases in plasma sodium and osmolality. It is recognized as one of the major contributing factors for cardiovascular diseases such as hypertension. The paraventricular nucleus (PVN) plays a pivotal role in osmotically driven sympathoexcitation and high blood pressure, the precise mechanisms of which are not fully understood. Recent evidence indicates that AVP released from magnocellular neurons might be involved in this process. Using a combination of in vivo and in situ studies, we sought to investigate whether AVP, acting on PVN neurons, can change mean arterial pressure (MAP) and sympathetic nerve activity (SNA) in euhydrated male rats. Furthermore, we wanted to determine whether V 1a receptors on PVN neurons would be involved in saltinduced sympathoexcitation and hypertension. In rats, 4 days of salt loading (NaCl 2%) elicited a significant increase in plasma osmolality (39 Ϯ 7 mosmol/kgH 2O), an increase in MAP (26 Ϯ 2 mmHg, P Ͻ 0.001), and sympathoexcitation compared with euhydrated rats. Microinjection of AVP into the PVN of conscious euhydrated animals (100 nl, 3 M) elicited a pressor response (14 Ϯ 2 mmHg) and a significant increase in lumbar SNA (100 nl, 1 mM) (19 Ϯ 5%). Pretreatment with a V 1a receptor antagonist, microinjected bilaterally into the PVN of salt-loaded animals, elicited a decrease in lumbar SNA (Ϫ14 Ϯ 5%) and MAP (Ϫ19 Ϯ 5 mmHg), when compared with the euhydrated group. Our findings show that AVP plays an important role in modulating the salt-induced sympathoexcitation and high blood pressure, via V 1a receptors, within the PVN of male rats. As such, V 1a receptors in the PVN might contribute to neurogenic hypertension in individuals consuming a high-salt diet.vasopressin; paraventricular nucleus of the hypothalamus; salt loading; sympathoexcitation; hypertension A HIGH DIETARY INTAKE OF SALT is one of the major contributing factors to cardiovascular diseases, such as hypertension (11,12,32). High-salt diets can lead to a hydromineral imbalance and increases the plasma sodium concentrations and osmolality. This, in turn, can activate central hypothalamic nuclei that elevate sympathetic outflow and arterial blood pressure (BP), leading to a disorder referred to as salt-sensitive neurogenic hypertension (33).Osmotic perturbations are primarily sensed by osmosensing neurons located in brain regions that lack a blood-brain barrier termed circumventricular organs (CVOs). Under systemic hyperosmotic conditions, the CVOs are activated and send excitatory inputs to the paraventricular nucleus of the hypothalamus (PVN), an important integrative center involved in the autonomic and neuroendocrine functions to maintain body fluids and cardiovascular homeostasis (14,19,28). The PVN lies adjacent to the third ventricle in the anterior hypothalamus, and it is composed of magnocellular neurons (MCNs) and parvocellular neurons (PCN). The PCN send projections to autonomic nuclei, such as the rostral ventrolateral medulla (RVLM) and intermediola...

Concurrent training (i.e., combination of endurance with strength training) may result in negative interference on strength performance. Moreover, there are indications that the magnitude of this interference is dependent on endurance exercise mode. Thus, this study aimed to verify the acute effects of previous running and cycling on strength endurance performance. After the determination of the maximum intensity reached (Imax) during treadmill running and cycle ergometer pedaling and half-squat maximum strength (1 repetition maximum [1RM]), 10 physically active men were submitted to 3 experimental conditions: control condition (S) comprised of 4 sets of maximum repetitions at 80% 1RM, intermittent running (RS), and cycling (CS) conditions (15 × 1 minute:1 minute in the Imax) followed by the strength exercise (S). Maximum number of repetitions (MNR), total session volume (TV), and vastus lateralis electromyographic signal (VLRMS) were analyzed. It was observed that MNR and TV performed in set 1 in the S condition was superior to that performed in set 1 in the RS (p < 0.001) and CS (p < 0.001) conditions; and set 2 in the S condition was superior to set 2 only in the CS for the MNR (p = 0.032) and TV (p = 0.012). For the VLRMS, there was a main effect for repetition, with higher values in the last repetition compared with the second one (p < 0.01). In conclusion, an aerobic exercise bout before strength exercise impairs the subsequent strength endurance performance. In addition, the magnitude of the interference effect was higher after the aerobic cycling exercise.

1RM: Maximum dynamic strength; AnT: Anaerobic threshold; Ca: Calcium; CO: Carbon dioxide; CT: Concurrent training; K: potassium; [La]: Lactate concentration; MVIC: Maximum voluntary isometric contraction; O: Oxygen; P: inorganic phosphate; PT: Peak twitch torque; TPT: Time to peak twitch torque; 1/2 RT: Half relaxation time; RMS: Root mean square; RTD: Average rate of twitch torque development; SE: Strength-endurance; TV: Total volume load; VA: Voluntary activation; VO: Oxygen uptake; VOpeak: Peak oxygen uptake.

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This review analyzes relevant variables involved in acute interference effects of concurrent training (CT) sessions of aerobic exercise followed by strength exercises. The aerobic exercise intensity, mode, volume, duration of recovery interval between exercises, muscle groups involved, and utilization of ergogenic aids are the variables identified in this review. High-intensity interval aerobic exercises result in more pronounced negative effects on strength-endurance exercise but not in maximal strength. Cycling results in more negative effects on strengthendurance performance exercise than running. A 4-hour to 8-hour recovery interval seems to be enough to avoid interference on strength-endurance performance. Reduction in strengthendurance performance is located in muscle groups involved in both exercises. Low aerobic exercise volume (3 km) with ;18 minutes of duration does not diminish strength endurance, whereas higher volumes (5 and 7 km) with ;30 and ;42 minutes of duration, respectively, generate impairments. Caffeine, carbohydrate, and beta-alanine are not able to revert the deleterious effect on strengthendurance performance, whereas creatine and capsaicin analog supplementation are. Thus, these variables must be taken into consideration to prescribe and organize a CT session. This information may help coaches to organize exercise sessions that minimize or avoid the impairment in strength performance after aerobic exercises.