Search

de Freitas Brito, A, Brasileiro Santos, MdS, Coutinho de Oliveira, CV, and da Cruz Santos, A. Postexercise hypotension is volume-dependent in hypertensives: autonomic and forearm blood responses. J Strength Cond Res 33(1): 234-241, 2019-The purpose of this study was to evaluate the effect of 2 sessions of resistance exercise (RE) with different volumes on postexercise hypotension (PEH), forearm blood flow (FBF), and cardiac autonomic balance (LF/HF) in hypertensive elderly woman. The study was conducted with 16 hypertensive elderly (25.7 ± 3 kg·m², 55.5 ± 3 years) subjected to 3 experimental sessions, i.e., a control session, exercise with a set (S1), and exercise with 3 sets (S3). For each session, the subjects were evaluated before and after intervention. In the preintervention period, blood pressure (BP), FBF, and LF/HF were measured after 10 minutes of rest in the supine position. Thereafter, the subjects were taken to the gym to perform their exercise sessions or remained at rest during the same period. Both S1 and S3 comprised a set of ten repetitions of 10 exercises, with an interval of 90 seconds between exercises. Subsequently, the measurements were again performed at 10, 30, 50, 70, and 90 minutes of recovery (postintervention) in the supine position. Postexercise hypotension (systolic/diastolic) was greater in S3 than in S1 (-26 ± 4/-14 ± 5 mm Hg vs. -18 ± 5/-8 ± 5 mm Hg, p ≤ 0.05). Similarly, FBF and cardiac LF/HF increased in both sessions, being more evident in S3 than in S1 (4.98 ± 0.32 vs. 4.36 ± 0.27 ml·min·100 ml, p ≤ 0.05; and LF/HF = 1.69 ± 0.225 vs. 1.37 ± 0.13 p ≤ 0.05, respectively). We conclude that a single RE session with 3 series were able to promote higher PEH in hypertensive women, and this phenomenon was accompanied by increased FBF and increased cardiac autonomic activity.

Carbohydrate ingestion at the end of a single exercise is recognized as delaying fatigue and accelerating recovery, but whether chronic ingestion can prevent overtraining during periods of intense training has not yet been elucidated. This study aimed to determine whether carbohydrate supplementation minimizes overtraining in Wistar rats. The animals underwent 11 weeks of training (running) on a treadmill, and the last 3 weeks were designed to induce overtraining. One group was supplemented with carbohydrates (EX-CHO) (n = 13), 1 group had no supplementation (EX) (n = 10), and a third group remained inactive (C) (n = 9). Performance tests were given before training (Pr1) and at the 8th (Pr2) and 11th (Pr3) training week. Food intake, body weight, testosterone, cortisol, malondialdehyde, creatine kinase, and activities of the PI3-K, Akt-1, mTOR, and GSK-3 enzymes were measured. In the EX group, there was a significant 32.6% performance decrease at Pr3 when compared with Pr2. In addition, at protocol completion, the EX-CHO group had a greater gastrocnemius weight than did the C group (p = 0.02), which the EX group did not. Training caused anorexia, decreased testosterone (p = 0.001), and increased malondialdehyde (p = 0.009) in both exercise groups compared with the C group, with no influence of carbohydrate supplementation on these variables (p > 0.05). Compared with in the C group, the activity of Akt-1 was higher in the EX-CHO group but not in the EX group (p = 0.013). Carbohydrate supplementation promoted an attenuation in the performance decrement and maintained gastrocnemius muscle mass in animals that had undergone overtraining protocols, which was accompanied by increased activity of the Akt-1 molecular indicator.

The purpose of this study was to evaluate the effect of high-intensity resistance exercise (RE) sessions on blood pressure (BP), heart rate (HR), cardiac autonomic modulation, and forearm blood flow (FBF). Sixteen trained hypertensive women (n = 16, 56 ± 3 years) completed the following 3 experimental sessions: control (CS), RE at 50% (EX50%), and RE at 80% (EX80%) of 1 repetition maximum (1RM). Both EX50% and EX80% comprised a set of 10 repetitions of 10 exercises, with an interval of 90 seconds between exercises. Measurements were taken preintervention and postintervention (at 10, 30, 50, 70, and 90 minutes of recovery). Reductions in systolic/diastolic BP after exercise were greater in EX80% (largest declines, -29 ± 4/-14 ± 5 mm Hg) than EX50% (largest declines, -18 ± 6/-8 ± 5 mm Hg, p ≤ 0.05). Heart rate and cardiac sympathovagal balance (LF/HF) increased more in relation to pre-exercise values in EX80% than EX50% (largest increases 96 ± 3 vs. 90 ± 4 b·min, LF/HF = 1.77 ± 0.25 vs. 1.40 ± 0.20, respectively, p ≤ 0.05). Increases in FBF and hyperemia was also higher in EX80% than EX50% compared with pre-exercise (4.97 ± 0.28 vs. 4.36 ± 0.27 ml·min·100 ml and 5.90 ± 0.20 vs. 5.38 ± 0.25 ml·min·100 ml; p ≤ 0.05, respectively). These results suggest that RE of higher intensity promoted greater postexercise hypotension accompanied by greater increases in FBF, vasodilator response, HR, and cardiac sympathovagal balance.