16 research outputs found
Respiratory muscle training positively affects vasomotor response in young healthy women
Vasomotor response is related to the capacity of the vessel to maintain vascular tone within a narrow range. Two main control mechanisms are involved: the autonomic control of the sympathetic neural drive (global control) and the endothelial smooth cells capacity to respond to mechanical stress by releasing vasoactive factors (peripheral control). The aim of this study was to evaluate the effects of respiratory muscle training (RMT) on vasomotor response, assessed by flow-mediated dilation (FMD) and heart rate variability, in young healthy females. The hypothesis was that RMT could enhance the balance between sympa- thetic and parasympathetic neural drive and reduce vessel shear stress. Thus, twenty-four women were randomly assigned to either RMT or SHAM group. Maximal inspiratory mouth pressure and maximum voluntary ventilation were utilized to assess the effectiveness of the RMT program, which consisted of three sessions of isocapnic hyperventilation/ week for eight weeks, (twenty-four training sessions). Heart rate variability assessed autonomic bal- ance, a global factor regulating the vasomotor response. Endothelial function was deter- mined by measuring brachial artery vasodilation normalized by shear rate (%FMD/SR). After RMT, but not SHAM, maximal inspiratory mouth pressure and maximum voluntary ventilation increased significantly (+31% and +16%, respectively). Changes in heart rate variability were negligible in both groups. Only RMT exhibited a significant increase in % FMD/SR (+45%; p\u3c0.05). These data suggest a positive effect of RMT on vasomotor response that may be due to a reduction in arterial shear stress, and not through modulation of sympatho-vagal balance
Efficacia di un training di regolazione delle emozioni in un gruppo di studenti universitari.
La regolazione emotiva (RE) è fondamentale per il benessere psicofisico degli studenti universitari che spesso si trovano a fronteggiare situazioni stressanti e stimoli del tutto nuovi. In letteratura sono pochi gli studi che verifichino gli effetti di training specifici sulla RE con studenti universitari. L’obiettivo di questo studio è quello di misurare l’efficacia di un un training di RE volto ad incrementare l’utilizzo della strategia di rivalutazione cognitiva e a ridurre l’utilizzo della soppressione espressiva, strategie di regolazione emotiva associate in letteratura rispettivamente ad outcome psicosociali positivi e negativi. L’obiettivo secondario, invece, è quello di misurare la sua efficacia nel ridurre i sintomi legati ad ansia, depressione e insonnia. I punteggi dei questionari somministrati al pre e al post assessment sono analizzati confrontando il gruppo sperimentale di studenti universitari (n = 18) con un gruppo di controllo (n = 16). I risultati evidenziano che il gruppo dei partecipanti al training di RE riportano punteggi significativamente più bassi al post training nella scala di soppressione espressiva rispetto ai controlli. Si registrano punteggi significativamente più bassi anche per i sintomi di ansia, seppure al pari dei controlli. Non emergono altri risultati significativi. Questo studio pilota presenta interessanti risultati preliminari di efficacia, evidenziando la necessità di replicare lo studio in un campione più ampio per la sua potenziale applicazione a livello clinico e subclinico.Emotion Regulation (ER) plays a critical role in individual psychological and physical well-being, especially in college students who mismanage school-related stress and new stimuli. Only a few studies have attempted to determine the effectiveness of emotion regulation training with both adults and college students. The first aim of this study is to evaluate the effectiveness of ER training program in increasing the use of cognitive reappraisal and in decreasing the use of expressive suppression, two ER strategies respectively related to adaptive and maladaptive psychosocial outcomes. The secondary purpose is to examine the effect of the ER training on the reduction of anxiety, depression and insomnia symptoms. The mean scores of pre-and post-assessment were analyzed by comparing the experimental group of students (N = 18) with a control group (N = 16) and controlling for gender. Students who received ER training reported significant lower post-training scores on expressive suppression than controls. Significant lower post training symptoms of anxiety were observed, although scores did not differ between groups. No significant results emerged for the other investigated issues. This pilot study provided preliminary results on the ER training effectiveness, thus highlighting its potential clinical and subclinical application. It is recommended to replicate the study in a larger sample size using more sophisticated methods
Correlation between stiffness and electromechanical delay components during muscle contraction and relaxation before and after static stretching
The study was aimed at assessing possible correlations of the electromechanical delay components during muscle contraction (DelayTOT) and relaxation (R-DelayTOT), with muscle-tendon unit (MTU), muscle, and tendon stiffness before and after static stretching (SS). Plantarflexor muscles' maximum voluntary torque (Tmax) was measured in 18 male participants (age 24\ub13yrs; body mass 76.4\ub18.9kg; stature 1.78\ub10.09m; mean\ub1SD). During Tmax, surface electromyogram (EMG), mechanomyogram, and force signals were detected. DelayTOT and R-DelayTOT with their electrochemical and mechanical components were calculated. Passive torque and myotendinous junction displacement were assessed at 0\ub0, 10\ub0 and 20\ub0 of dorsiflexion to determine MTU, muscle and tendon stiffness. The same protocol was repeated after SS. DelayTOT, R-DelayTOT and their mainly mechanical components correlated with MTU, muscle and tendon stiffness, both before (R(2) from 0.562 to 0.894; p<0.001) and after SS (R(2) from 0.726 to 0.955; p<0.001). SS decreased Tmax (-14%; p<0.001) and lengthened almost all the DelayTOT and R-DelayTOT components (from +5.9% to +30.5%; p<0.05). Correlations were found only between stiffness and the mechanical components of DelayTOT and R-DelayTOT. Correlations persisted after SS but delays increased to a higher extent than stiffness, indicating a complexity of the relationship between stiffness and delays that will be discussed in the manuscript
Central and peripheral responses to static and dynamic stretch of skeletal muscle: mechano- and metaboreflex implications
Passive static stretching (SS), circulatory cuff occlusion (CCO), and the combination of both (SS + CCO) have been used to investigate the mechano- and metaboreflex, respectively. However, the effects of dynamic stretching (DS) alone or in combination with CCO (DS + CCO) on the same reflexes have never been explored. The aim of the study was to compare central and peripheral hemodynamic responses to DS, SS, DS + CCO, and SS + CCO. In 10 participants, femoral blood flow (FBF), heart rate (HR), cardiac output (CO), and mean arterial pressure (MAP) were assessed during DS and SS of the quadriceps muscle with and without CCO. Blood lactate concentration [La(-)] in the lower limb undergoing CCO was also measured. FBF increased significantly in DS and SS by 365 \ub1 98 and 377 \ub1 102 ml/min, respectively. Compared with baseline, hyperemia was negligible during DS + CCO and SS + CCO (+11 \ub1 98 and +5 \ub1 87 ml/min, respectively). DS generated a significant, sustained increase in HR and CO ( 3c40s), while SS induced a blunted and delayed cardioacceleration ( 3c20 s). After CCO, [La(-)] in the lower limb increased by 135%. Changes in HR and CO during DS + CCO and SS + CCO were similar to DS and SS alone. MAP decreased significantly by 3c5% during DS and SS, did not change in DS + CCO, and increased by 4% in SS + CCO. The present data indicate a reduced mechanoreflex response to SS compared with DS (i.e., different HR and CO changes). SS evoked a hyperemia similar to DS. The similar central hemodynamics recorded during stretching and [La(-)] accumulation suggest a marginal interaction between mechano- and metaboreflex
Respiratory muscle training positively affects vasomotor response in young healthy women.
Vasomotor response is related to the capacity of the vessel to maintain vascular tone within a narrow range. Two main control mechanisms are involved: the autonomic control of the sympathetic neural drive (global control) and the endothelial smooth cells capacity to respond to mechanical stress by releasing vasoactive factors (peripheral control). The aim of this study was to evaluate the effects of respiratory muscle training (RMT) on vasomotor response, assessed by flow-mediated dilation (FMD) and heart rate variability, in young healthy females. The hypothesis was that RMT could enhance the balance between sympathetic and parasympathetic neural drive and reduce vessel shear stress. Thus, twenty-four women were randomly assigned to either RMT or SHAM group. Maximal inspiratory mouth pressure and maximum voluntary ventilation were utilized to assess the effectiveness of the RMT program, which consisted of three sessions of isocapnic hyperventilation/ week for eight weeks, (twenty-four training sessions). Heart rate variability assessed autonomic balance, a global factor regulating the vasomotor response. Endothelial function was determined by measuring brachial artery vasodilation normalized by shear rate (%FMD/SR). After RMT, but not SHAM, maximal inspiratory mouth pressure and maximum voluntary ventilation increased significantly (+31% and +16%, respectively). Changes in heart rate variability were negligible in both groups. Only RMT exhibited a significant increase in %FMD/SR (+45%; p<0.05). These data suggest a positive effect of RMT on vasomotor response that may be due to a reduction in arterial shear stress, and not through modulation of sympatho-vagal balance
Acute effects of static stretching on skeletal muscle relaxation at different ankle joint angles
Purpose: By combining electromyographic (EMG), mechanomyographic (MMG) and force analysis, the electromechanical delay during muscle relaxation (R-DelayTOT) was partitioned into electrochemical and mechanical components. The study aimed to evaluate the effects of changes in joint angle on R-DelayTOT components during relaxation after electrically evoked contractions before and after static stretching (SS) administration. Methods: Nineteen male participants (age 24 \ub1 3 years; body mass 76.4 \ub1 8.9 kg; stature 1.78 \ub1 0.09 m; mean \ub1 SD) were evaluated. Passive torque (Tpass) of the plantarflexor muscles was measured at 0\ub0, 10\ub0, and 20\ub0 of dorsiflexion to determine joint stiffness. The maximum electrically evoked torque (pT) was also recorded at each angle. During pT, force, EMG and MMG signals were detected for offline calculations of R-DelayTOT and its electrochemical and mechanical components. The same procedures were repeated after SS. Results: With increase in dorsiflexion angle, joint stiffness increased while R-DelayTOT and its mainly mechanical components decreased (from 128 to 20 %, P < 0.05). After SS, joint stiffness decreased (from 16 to 20 %, P < 0.05), while R-DelayTOT and its mainly mechanical components lengthened (from 8 to 28.5 %, P < 0.05). Moreover, post-SS R-DelayTOT and its components decreased with the increase in joint angle (from 1213 to 31 %, P < 0.05). Conclusion: The reduction in R-DelayTOT with increase in joint angle could be ascribed to the increase in joint stiffness, and not to alterations of the electrochemical processes during relaxation. SS lengthened R-DelayTOT and its components with a concomitant decrease in joint stiffness. Nevertheless, the reduction of the R-DelayTOT mainly mechanical components seen with dorsiflexion was similar to that before SS. \ua9 2016, Springer-Verlag Italia