RESUMEN
Ischemic preconditioning (IPC), cyclical bouts of nonlethal ischemia, provides immediate protection against ischemic injury, which is evident both locally and remotely. Given the similarities in protective effects of exercise with ischemic preconditioning, we examined whether handgrip exercise also offers protection against endothelial ischemia-reperfusion (IR) injury and whether this protection is equally present in the local (exercised) and remote (contralateral, nonexercised) arm. Fifteen healthy males (age, 24 ± 3 yr; body mass index, 25 ± 2 kg/m2) attended the laboratory on three occasions. Bilateral brachial artery flow-mediated dilation (FMD) was examined at rest and after a temporary IR injury in the upper arm. Before the IR injury, in the dominant (local) arm, participants performed (randomized, counterbalanced): 1) 4 × 5 min unilateral handgrip exercise (50% maximal voluntary contraction), 2) 4 × 5 min unilateral IPC (220 mmHg), or 3) 4 × 5 min rest (control). Data were analyzed using repeated-measures general linear models. Allometrically scaled FMD declined after IR in the control condition (4.6 ± 1.3% to 2.2 ± 1.7%, P < 0.001), as well as following handgrip exercise (4.6 ± 1.6% to 3.4 ± 1.9%, P = 0.01), however, was significantly attenuated with IPC (4.5 ± 1.4% to 3.8 ± 3.5%, P = 0.14). There were no differences between the local and remote arm. Our findings reinforce the established protective effects of IPC in young, healthy males and also highlight a novel strategy to protect against IR injury with handgrip exercise, which warrants further study.
Asunto(s)
Precondicionamiento Isquémico , Daño por Reperfusión , Adulto , Humanos , Masculino , Adulto Joven , Endotelio Vascular , Fuerza de la Mano , Isquemia , Daño por Reperfusión/prevención & controlRESUMEN
Montrezol, FT, Marinho, R, Mota, GdFAd, D'almeida, V, de Oliveira, EM, Gomes, RJ, and Medeiros, A. ACE gene plays a key role in reducing blood pressure in the hyperintensive elderly after resistance training. J Strength Cond Res 33(4): 1119-1129, 2019-Hypertension is a difficult disease to control and exercise training plays a key role in hypertension control. Some individuals are not responsive to exercise training; so, we highlight the polymorphism of I allele of angiotensin-converting enzyme (ACE) as a factor responsible for this lack of responsiveness. The aim of this study was to evaluate the influence of ACE insertion/deletion genotypes on effects of resistance training on blood pressure (BP) and chronic inflammation. Eighty-six hypertensive volunteers, aged between 60 and 80, were evaluated. They performed 16 weeks of resistance training at 50% of 1 maximal repetition. The greatest benefits were seen on homozygous of the Insertion allele, whom presented reduction of systolic blood pressure (SBP: 129.31 ± 13.34 vs. 122.56 ± 9.68 mm Hg, p < 0.001) and diastolic blood pressure (DBP: 79.18 ± 8.05 vs. 70.12 ± 7.71 mm Hg, p < 0.01) during daytime period, and in 24-hour period (SBP: 127.12 ± 13.65 vs. 121.06± 9.68 mm Hg, p < 0.001 and DBP: 71.87 ± 8.39 vs. 68.75 ± 8.72 mm Hg, p < 0.05) and also increased circulating adiponectin levels (4.04 ± 1.79 vs. 6.00 ± 2.81 ng·ml, p < 0.01). Other genotypes showed no changes in BP and biochemical parameters. Our results suggest a cardio protective factor of I allele because only those homozygous showed reductions in BP and increases in adiponectin.