Post-dynamic, isometric and combined resistance exercise responses in medicated hypertensive men.

This study investigated the effects of dynamic resistance exercise (DRE), isometric handgrip exercise (IHE) and combined resistance exercise (DRE+IHE) on post-exercise hypotension (PEH) and its hemodynamic, autonomic, and vascular mechanisms. For that, 70 medicated hypertensives men (52 ± 8 years) were randomly allocated to perform one of the following interventions: DRE (3 sets, 8 exercises, 50% of 1RM), IHE (4 sets, 2 min, 30% of MVC), CRE (DRE+IHE) and control (CON, seated rest). Before and after the interventions, blood pressure (BP), systemic hemodynamics, cardiovascular autonomic modulation and brachial vascular parameters were evaluated. After the DRE and CRE, systolic and mean BP decreased (SBP = -7 ± 6 and -8 ± 8 mmHg; MBP -4 ± 5 and -5 ± 5 mmHg, respectively, all P < 0.05), vascular conductance increased (+ 0.47 ± 0.61 and +0.40 ± 0.47 ml.min-1.mmHg-1, respectively, both P < 0.05) and baroreflex sensitivity decreased (-0.15 ± 0.38 and -0.29 ± 0.47 ms/mmHg, respectively, both P < 0.05) in comparison to pre-exercise values. No variable presented any significant change after IHE. The responses observed after CRE were similar to DRE and significantly different from CON and IHE. In conclusion, DRE, but not IHE, elicits PEH, which happens concomitantly to skeletal muscle vasodilation and decreased baroreflex sensitivity. Moreover, adding IHE to DRE does not potentiate PEH and neither changes its mechanisms.Clinical Trial Registration: Data from this study derived from an ongoing longitudinal clinical trial approved by the Institution's Ethics Committee of Human Research (process 2.870.688) and registered at the Brazilian Clinical Trials (RBR-4fgknb) at http://www.ensaiosclinicos.gov.br .

Effects of dynamic, isometric and combined resistance training on blood pressure and its mechanisms in hypertensive men.

Although dynamic resistance training (DRT) and isometric handgrip training (IHT) may decrease blood pressure (BP) in hypertensives, the effects of these types of training have not been directly compared, and a possible additive effect of combining IHT to DRT (combined resistance training-CRT), has not been investigated. Thus, this study compared the effects of DRT, IHT and CRT on BP, systemic hemodynamics, vascular function, and cardiovascular autonomic modulation. Sixty-two middle-aged men with treated hypertension were randomly allocated among four groups: DRT (8 exercises, 50% of 1RM, 3 sets until moderate fatigue), IHT (30% of MVC, 4 sets of 2 min), CRT (DRT + IHT) and control (CON - stretching). In all groups, the interventions were administered 3 times/week for 10 weeks. Pre- and post-interventions, BP, systemic hemodynamics, vascular function and cardiovascular autonomic modulation were assessed. ANOVAs and ANCOVAs adjusted for pre-intervention values were employed for analysis. Systolic BP decreased similarly with DRT and CRT (125 ± 11 vs. 119 ± 12 and 128 ± 12 vs. 119 ± 12 mmHg, respectively; P < 0.05), while peak blood flow during reactive hyperaemia (a marker of microvascular function) increased similarly in these groups (774 ± 377 vs. 1067 ± 461 and 654 ± 321 vs. 954 ± 464 mL/min, respectively, P < 0.05). DRT and CRT did not change systemic hemodynamics, flow-mediated dilation, and cardiovascular autonomic modulation. In addition, none of the variables were changed by IHT. In conclusion, DRT, but not IHT, improved BP and microvascular function in treated hypertensive men. CRT did not have any additional effect in comparison with DRT alone.

Poor sleep quality is associated with cardiac autonomic dysfunction in treated hypertensive men.

Hypertensives present cardiac autonomic dysfunction. Reduction in sleep quality increases blood pressure (BP) and favors hypertension development. Previous studies suggested a relationship between cardiovascular autonomic dysfunction and sleep quality, but it is unclear whether this association is present in hypertensives. Thus, this study evaluated the relationship between sleep quality and cardiac autonomic modulation in hypertensives. Forty-seven middle-aged hypertensive men under consistent anti-hypertensive treatment were assessed for sleep quality by the Pittsburgh Sleep Quality Index (PSQI-higher score means worse sleep quality). Additionally, their beat-by-beat BP and heart rate (HR) were recorded, and cardiac autonomic modulation was assessed by their variabilities. Mann-Whitney and t tests were used to compare different sleep quality groups: poor (PSQI > 5, n = 24) vs good (PSQI ≤ 5, n = 23), and Spearman's correlations to investigate associations between sleep quality and autonomic markers. Patients with poor sleep quality presented lower cardiac parasympathetic modulation (HR high-frequency band = 26 ± 13 vs 36 ± 15 nu, P = .03; HR total variance = 951 ± 1373 vs 1608 ± 2272 ms2 , P = .05) and cardiac baroreflex sensitivity (4.5 ± 2.3 vs 7.1 ± 3.7 ms/mm Hg, P = .01). Additionally, sleep quality score presented significant positive correlation with HR (r = +0.34, P = .02) and negative correlations with HR high-frequency band (r = -0.34, P = .03), HR total variance (r = -0.35, P = .02), and cardiac baroreflex sensitivity (r = -0.42, P = .01), showing that poor sleep quality is associated with higher HR and lower cardiac parasympathetic modulation and baroreflex sensitivity. In conclusion, in treated hypertensive men, poor sleep quality is associated with cardiac autonomic dysfunction.