Effect of Strength Training on Oxidative Stress and the Correlation of the Same with Forearm Vasodilatation and Blood Pressure of Hypertensive Elderly Women: A Randomized Clinical Trial

Abstract

The aim of the study was to evaluate the effect of strength training on oxidative stress and the correlation of the same with forearm vasodilatation and mean blood pressure of hypertensive elderly women, at rest (basal) and during a static handgrip exercise. Insufficiently active hypertensive elderly women (N = 25; mean age = 66.1 years) were randomized into a 10 week strength training group (n = 13) or control (n = 12) group. Plasma malondialdehyde (MDA), total antioxidant capacity (TAC), plasma nitrite (NO ₂ ^-), forearm blood flow (FBF), mean blood pressure (MBP) and vascular conductance ([FBF / MBP] x 100) were evaluated before and after the completion of the interventions. The strength training group increased the TAC (pre: Median = 39.0; Interquartile range = 34.0–41.5% vs post: Median = 44.0; Interquartile range = 38.0–51.5%; p = 0.006) and reduced the MDA (pre: 4.94 ± 1.10 μM vs post: 3.90 ± 1.35 μM; p = 0.025; CI-95%: -1.92 –-0.16 μM). The strength training group increased basal vascular conductance (VC) (pre: 3.56 ±0.88 units vs post: 5.21 ±1.28 units; p = 0.001; CI-95%: 0.93–2.38 units) and decreased basal MBP (pre: 93.1 ±6.3 mmHg vs post: 88.9 ±5.4 mmHg; p = 0.035; CI-95%: -8.0 –-0.4 mmHg). Such changes were also observed during static handgrip exercise. A moderate correlation was observed between changes in basal VC and MBP with changes in NO ₂ ^- (ΔVC → r = -0.56, p = 0.047; ΔMBP → r = -0.41, p = 0.168) and MDA (ΔVC → r = 0.64, p = 0.019; ΔMBP → r = 0.31, p = 0.305). The strength training program reduced the oxidative stress of the hypertensive elderly women and this reduction was moderately correlated with their cardiovascular benefits.

Trial Registration: ensaiosclinicos.gov.br RBR-48c29w