Clinical Research Directory

Acute and Chronic Effects of Combined Training on BP in Hypertensives

Dynamic strength training (DST) is widely recognized for promoting neuromuscular adaptations such as increased strength and hypertrophy. It is currently endorsed by treatment and prevention guidelines for systemic arterial hypertension (SAH) due to its significant effect on lowering blood pressure (BP). However, when comparing BP reduction values, isometric strength training (IST) stands out with greater magnitudes of BP reduction, although without the neuromuscular adaptations seen in DST. Given their similarities, a combination of these strategies through combined strength training (CST) is possible but has not yet been evaluated. The researchers hypothesized that CST may have an additive effect compared with DST and IST alone in reducing ambulatory BP. Therefore, the objective of the present thesis was to evaluate and compare the effects of CST, DST, and IST on regulatory variables of ambulatory BP in medicated middle-aged hypertensive patients. This thesis is structured in two parts: (1) a crossover study with medicated middle-aged hypertensive patients to identify autonomic, endothelial, and vascular responses related to ambulatory BP after a single session of CST, DST, and IST; and (2) a randomized clinical trial to assess the chronic effects of CST, DST, and IST on regulatory variables of ambulatory BP in medicated middle-aged hypertensive patients.

Acute Effects of Bilateral Versus Unilateral Isometric Conditioning Activity on Jump Performance in Volleyball Players

This randomized crossover trial investigates the acute effects of bilateral and unilateral isometric conditioning activity on bilateral and unilateral jump performance in highly trained male volleyball players. Fourteen athletes will complete three experimental conditions in randomized order: bilateral isometric squat conditioning activity (BI), unilateral isometric squat conditioning activity (UNI), and a control condition consisting of low-intensity treadmill walking (CTRL). In both isometric conditions, participants will perform three sets of three maximal 3-second contractions, with 3-minute recovery intervals between sets. Jump performance will be assessed before each experimental condition and at 4, 8, and 12 minutes afterward using bilateral countermovement jumps and single-leg jumps performed separately with each lower limb. The primary aim of the study is to determine whether the mode of isometric conditioning activity, unilateral versus bilateral, influences the magnitude and time course of acute changes in jump performance. An additional objective is to assess whether the effects of the conditioning activity differ between bilateral and unilateral jumping tasks.

Acute Effects of Isometric Conditioning on Sprint, Jump and Change of Direction Performance in Youth Soccer Players

This study aims to examine the acute effects of an isometric conditioning activity on sprinting, jumping, and change-of-direction performance in elite youth soccer players. Twelve male soccer players aged 15-19 years from a professional academy will participate in a randomized crossover study. Each participant will complete two experimental sessions separated by one week. During each session, participants will perform a standardized warm-up followed by baseline performance tests including countermovement jumps, drop jumps, a 30-m sprint test, and a 505 change-of-direction test. After baseline testing, participants will complete one of two conditions in randomized order: (1) an isometric conditioning activity consisting of unilateral standing isometric calf raises, or (2) a control condition consisting of low-intensity treadmill walking. Performance tests will be repeated seven minutes after the intervention to assess acute changes in neuromuscular performance. Jump performance will be assessed using a dual force plate system sampling at 1000 Hz, and sprint performance will be measured using electronic timing gates. The study will be conducted on an indoor athletics runway located in a gymnasium. The results will help determine whether isometric conditioning activities can acutely enhance explosive performance in youth soccer players.