Evaluating Intraocular Pressure Alterations during Large Muscle Group Isometric Exercises with Varying Head and Body Positions.

Performing physical exercise affects intraocular pressure, and its elevation and fluctuations are the main risk factors for glaucoma development or progression. The aim of this study was to examine the acute alterations in intraocular pressure (IOP) during four unweighted isometric exercises and to determine whether the different head and body positions taken during exercise additionally affect IOP. Twelve healthy volunteers between the ages of 25 and 33 performed four isometric exercises: wall sit in neutral head and body position, elbow plank in prone head and body position, reverse plank in supine head and body position for 1 min, and right-side plank in lateral head and body position for 30 s. Intraocular pressure was measured by applanation portable tonometry, before performing the exercise, immediately after exercise completion, and after five minutes of rest. A significant acute increase in intraocular pressure was found as a response to the performance of the elbow plank (p < 0.01), the reverse plank (p < 0.001), and the right-side plank (p < 0.001). The wall sit exercise did not reveal a statistically significant IOP elevation (p = 0.232). Different head and body positions had no significant additional influence on IOP (F (3,33) = 0.611; p = 0.613), even though the alteration in IOP was found to be greater in exercises with a lower head and body position. Our data revealed that IOP elevation seems to be affected by the performance of the elbow plank, the reverse plank, and the right-side plank; and not by the wall sit exercise. More different isometric exercises should be examined to find ones that are safe to perform for glaucoma patients.

The Clinical Effects of Pharmacotherapy Combined with Blood Flow Restriction and Isometric Exercise Training in Rehabilitating Patients with Heart Failure with Reduced Ejection Fraction.

Heart failure with reduced ejection fraction (HFrEF) is associated with reduced cardiac function and impaired quality of life. Blood flow restriction (BFR) training is emerging as a potential adjunctive therapy. This study aimed at evaluating the efficacy of combination of BFR and isometric exercises on cardiac function, functional status, and quality of life in HFrEF patients. Totally 44 patients with HFrEF were equally divided into a control group and a combined treatment group. Both groups received standard pharmacotherapy and upper limb exercise, with the combined group also undergoing BFR and isometric exercise training. We assessed demographic and clinical characteristics, New York Heart Association (NYHA) functional classification, cardiac function parameters, serum Brain Natriuretic Peptide levels, physical capacity via the 6-minute walking test, and quality of life using the Heart Failure Questionnaire (Minnesota Living with Heart Failure Questionnaire). Post-treatment, the combined group significantly improved in NYHA classification (p = 0.012), with more patients shifting to a better class. Cardiac function improved in both groups, with the combined group showing a greater increase in mean left ventricular ejection fractions (p < 0.001), and reductions in left ventricular end-diastolic and end-systolic diameters (p < 0.05). The addition of BFR training to standard pharmacotherapy with upper limb exercise in HFrEF patients led to significant enhancements in cardiac function, functional status, and quality of life. These findings support the integration of BFR training into conventional HFrEF treatment regimens to maximize patient recovery outcomes.

Handgrip exercise does not alter CO2 -mediated cerebrovascular flow-mediated dilation.

Handgrip exercise (HG), a small muscle exercise, improves cognitive function and is expected to provide a useful exercise mode to maintain cerebral health. However, the effect of HG on cerebral blood flow regulation is not fully understood. The present study aimed to examine the effect of acute HG on cerebral endothelial function as one of the essential cerebral blood flow regulatory functions. Thirteen healthy young participants performed interval HG, consisting of 4 sets of 2 min HG at 25% of maximum voluntary contraction with 3 min recovery between each set. Cognitive performance was evaluated before and at 5 and 60 min after interval HG using the Go/No-Go task (reaction time and accuracy). The diameter and blood velocity of the internal carotid artery (ICA) were measured using a duplex Doppler ultrasound system. To assess cerebral endothelial function, hypercapnia (30 s of hypercapnia stimulation, end-tidal partial pressure of CO2 : +9 mmHg)-induced cerebrovascular flow-mediated dilatation (cFMD) was induced, calculated as relative peak dilatation from baseline diameter. The shear rate (SR) was calculated using the diameter and blood velocity of the ICA. As a result, cognitive performance improved only at 5 min after interval HG (reaction time, P = 0.008; accuracy, P = 0.186), whereas ICA SR during interval HG and cFMD after interval HG were unchanged (P = 0.313 and P = 0.440, respectively). These results suggest that enhancement in cerebral endothelial function is not an essential mechanism responsible for acute HG-induced cognitive improvement. NEW FINDINGS: What is the central question of this study? Does handgrip exercise, a small muscle exercise, improve cerebral endothelial function? What is the main finding and its importance? Acute interval isometric handgrip exercise (2 min of exercise at 25% maximum voluntary contraction, followed by 3 min of recovery, repeated for a total of 4 sets) did not improve cerebral endothelial function. Since the cerebrovascular shear rate did not change during exercise, it is possible that acute handgrip exercise is not sufficient stimulation to improve cerebral endothelial function.

Surface Electromyography-Driven Parameters for Representing Muscle Mass and Strength.

The need for developing a simple and effective assessment tool for muscle mass has been increasing in a rapidly aging society. This study aimed to evaluate the feasibility of the surface electromyography (sEMG) parameters for estimating muscle mass. Overall, 212 healthy volunteers participated in this study. Maximal voluntary contraction (MVC) strength and root mean square (RMS) values of motor unit potentials from surface electrodes on each muscle (biceps brachii, triceps brachii, biceps femoris, rectus femoris) during isometric exercises of elbow flexion (EF), elbow extension (EE), knee flexion (KF), knee extension (KE) were acquired. New variables (MeanRMS, MaxRMS, and RatioRMS) were calculated from RMS values according to each exercise. Bioimpedance analysis (BIA) was performed to determine the segmental lean mass (SLM), segmental fat mass (SFM), and appendicular skeletal muscle mass (ASM). Muscle thicknesses were measured using ultrasonography (US). sEMG parameters showed positive correlations with MVC strength, SLM, ASM, and muscle thickness measured by US, but showed negative correlations with SFM. An equation was developed for ASM: ASM = -26.04 + 20.345 × Height + 0.178 × weight - 2.065 × (1, if female; 0, if male) + 0.327 × RatioRMS(KF) + 0.965 × MeanRMS(EE) (SEE = 1.167, adjusted R2 = 0.934). sEMG parameters in controlled conditions may represent overall muscle strength and muscle mass in healthy individuals.

Cardiovascular responses to static handgrip exercise and postexercise ischemia in heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) is characterized by reduced ability to sustain physical activity that may be due partly to disease-related changes in autonomic function that contribute to dysregulated cardiovascular control during muscular contraction. Thus, we used a combination of static handgrip exercise (HG) and postexercise ischemia (PEI) to examine the pressor response to exercise and isolate the skeletal muscle metaboreflex, respectively. Mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), and total peripheral resistance (TPR) were assessed during 2-min of static HG at 30 and 40% of maximum voluntary contraction (MVC) and subsequent PEI in 16 patients with HFpEF and 17 healthy, similarly aged controls. Changes in MAP were lower in patients with HFpEF compared with controls during both 30%MVC (Δ11 ± 7 vs. Δ15 ± 8 mmHg) and 40%MVC (Δ19 ± 14 vs. Δ30 ± 8 mmHg), and a similar pattern of response was evident during PEI (30%MVC: Δ8 ± 5 vs. Δ12 ± 8 mmHg; 40%MVC: Δ13 ± 10 vs. Δ18 ± 9 mmHg) (group effect: P = 0.078 and P = 0.017 at 30% and 40% MVC, respectively). Changes in HR, CO, and TPR did not differ between groups during HG or PEI (P > 0.05). Taken together, these data suggest a reduced pressor response to static muscle contractions in patients with HFpEF compared with similarly aged controls that may be mediated partly by a blunted muscle metaboreflex. These findings support a disease-related dysregulation in neural cardiovascular control that may reduce an ability to sustain physical activity in HFpEF.NEW & NOTEWORTHY The current investigation has identified a diminution in the exercise-induced rise in arterial blood pressure (BP) that persisted during postexercise ischemia (PEI) in an intensity-dependent manner in patients with heart failure with preserved ejection fraction (HFpEF) compared with older, healthy controls. These findings suggest that the pressor response to exercise is reduced in patients with HFpEF, and this deficit may be mediated, in part, by a blunted muscle metaboreflex, highlighting the consequences of impaired neural cardiovascular control during exercise in this patient group.

The effect of isometric exercise training on arterial stiffness: A randomized crossover controlled study.

Isometric exercise training (IET) is an effective intervention for the management of resting blood pressure (BP). However, the effects of IET on arterial stiffness remain largely unknown. Eighteen unmedicated physically inactive participants were recruited. Participants were randomly allocated in a cross-over design to 4 weeks of home-based wall squat IET and control period, separated by a 3-week washout period. Continuous beat-to-beat hemodynamics, including early and late systolic (sBP 1 and sBP 2, respectively) and diastolic blood pressure (dBP) were recorded for a period of 5 min and waveforms were extracted and analyzed to acquire the augmentation index (AIx) as a measure of arterial stiffness. sBP 1 (-7.7 ± 12.8 mmHg, p = 0.024), sBP 2 (-5.9 ± 9.9 mmHg, p = 0.042) and dBP (-4.4 ± 7.2 mmHg, p = 0.037) all significantly decreased following IET compared to the control period. Importantly, there was a significant reduction in AIx following IET (-6.6 ± 14.5%, p = 0.02) compared to the control period. There were also adjacent significant reductions in total peripheral resistance (-140.7 ± 65.8 dynes·cm-5, p = 0.042) and pulse pressure (-3.8 ± 4.2, p = 0.003) compared to the control period. This study demonstrates an improvement in arterial stiffness following a short-term IET intervention. These findings have important clinical implications regarding cardiovascular risk. Mechanistically, these results suggest that reductions in resting BP following IET are induced via favorable vascular adaptations, although the intricate details of such adaptations are not yet clear.

Ventilatory response to peripheral chemoreflex and muscle metaboreflex during static handgrip in healthy humans: evidence of hyperadditive integration.

NEW FINDINGS: What is the central question of this study? What is the effect of peripheral chemoreflex and muscle metaboreflex integration on ventilation regulation, and what is the effect of integration on breathing-related sensations and emotions? What is the main finding and its importance? Peripheral chemoreflex and muscle metaboreflex coactivation during isocapnic static handgrip exercise appeared to elicit a hyperadditive effect with regard to ventilation and an additive effect with regard to breathing-related sensations and emotions. These findings reveal the nature of the integration between two neural mechanisms that operate during small-muscle static exercise performed under hypoxia. ABSTRACT: Exercise augments the hypoxia-induced ventilatory response in an exercise intensity-dependent manner. A mutual influence of hypoxia-induced peripheral chemoreflex activation and exercise-induced muscle metaboreflex activation might mediate the augmentation phenomenon. However, the nature of these reflexes' integration (i.e., hyperadditive, additive or hypoadditive) remains unclear, and the coactivation effect on breathing-related sensations and emotions has not been explored. Accordingly, we investigated the effect of peripheral chemoreflex and muscle metaboreflex coactivation on ventilatory variables and breathing-related sensations and emotions during exercise. Fourteen healthy adults performed 2-min isocapnic static handgrip, first with the non-dominant hand and immediately after with the dominant hand. During the dominant hand exercise, we (a) did not manipulate either reflex (control); (b) activated the peripheral chemoreflex by hypoxia; (c) activated the muscle metaboreflex in the non-dominant arm by post-exercise circulatory occlusion (PECO); or (d) coactivated both reflexes by simultaneous hypoxia and PECO use. Ventilation response to coactivation of reflexes (mean ± SD, 13 ± 6 l/min) was greater than the sum of responses to separated activations of reflexes (mean ± SD, 8 ± 8 l/min, P = 0.005). Breathing-related sensory and emotional responses were similar between coactivation of reflexes and the sum of separate activations of reflexes. Thus, the peripheral chemoreflex and muscle metaboreflex integration during exercise appeared to be hyperadditive with regard to ventilation and additive with regard to breathing-related sensations and emotions in healthy adults.

Isometric Resistance Training to Manage Hypertension: Systematic Review and Meta-analysis.

PURPOSE OF REVIEW: Hypertension is the primary risk factor for cardiovascular disease and adequate blood pressure control is often elusive. The objective of this work was to conduct a meta-analysis of trial data of isometric resistance training (IRT) studies in people with hypertension, to establish if IRT produced an anti-hypertensive effect. A database search (PubMed, CINAHL, Cochrane Central Register of Controlled Trials, and MEDLINE) identified randomised controlled and crossover trials of IRT versus a sedentary or sham control group in adults with hypertension. RECENT FINDINGS: We included 12 studies (14 intervention groups) in the meta-analyses, with an aggregate of 415 participants. IRT reduced systolic blood pressure (SBP), mean difference (MD) - 7.47 mmHg (95%CI - 10.10, - 4.84), P < 0.01; diastolic blood pressure (DBP) MD - 3.17 mmHg (95%CI - 5.29, - 1.04), P < 0.01; and mean arterial blood pressure (MAP) MD - 7.19 mmHg (95%CI - 9.06, - 5.32), P < 0.0001. Office pulse pressure and resting heart rate was not significantly reduced, neither were 24-h or day-time ambulatory blood pressures (SBP, DBP). Night-time blood pressures, however, were significantly reduced with SBP MD - 4.28 mmHg (95%CI - 7.88, - 0.67), P = 0.02, and DBP MD - 2.22 mmHg (95%CI - 3.55, - 0.88), P < 0.01. IRT does lower SBP, DBP and MAP office and night-time ambulatory SBP and DBP, but not 24-h mean ambulatory blood pressures in people with hypertension.

Rapid adjustments to autonomic control of cardiac rhythm at the onset of isometric exercise in healthy young adults.

Sympathetic nervous system (SNS) and parasympathetic nervous system (PNS) influences on cardiac rhythm at the onset of exercise, a time of rapid autonomic adjustments, are clinically important areas of investigation. Continuous wavelet transform (CWT) involves time-frequency-based heart rate variability (HRV) analysis allowing investigation of autonomic influences on cardiac rhythm during short durations of exercise. Therefore, the purpose of this study was to characterize SNS and PNS influences on cardiac rhythm at the onset of isometric exercise in healthy young adults. CWT analysis was retrospectively applied to R-R interval data (electrocardiogram) previously collected from 14 healthy young adults (26 ± 2 years) who performed 30-s, one-legged, isometric, calf exercise at 70% maximal voluntary contraction (MVC; 70% MVC trial) or rested (0% MVC trial). Absolute and normalized low-frequency (aLF, nLF; 0.04-0.15 Hz) and high-frequency (aHF, nHF; 0.15-0.4 Hz) bands and LF/HF were used to analyze one 30-s baseline period and six 5-s time windows during the 30-s exercise (70% MVC) or rest (0% MVC). Statistical analysis involved two-way analysis of variance with post-hoc analysis. aHF, aLF, LF/HF, nHF, and nLF displayed a trial-time interaction (all p ≤ 0.027). In the 70% compared to the 0% MVC trial, aHF and nHF were lower after 5-30 s (all p ≤ 0.040), aLF was lower after 20-30 s (all p ≤ 0.011) and LF/HF and nLF were higher after 5-20 s (all p ≤ 0.045). These results indicate the reduction of the PNS influence on cardiac rhythm begins sooner than the augmentation of the SNS influence at the onset of isometric exercise in healthy young adults.

The autonomic and nociceptive response to acute exercise is impaired in people with knee osteoarthritis.

Objectives: An acute bout of exercise typically leads to short term exercise induced hypoalgesia (EIH), but this response is more variable in many chronic pain populations, including knee osteoarthritis (OA) and fibromyalgia (FM). There is evidence of autonomic nervous system (ANS) dysfunction in some chronic pain populations that may contribute to impaired EIH, but this has not been investigated in people with knee OA. The aim of this study was to assess the acute effects of isometric exercise on the nociceptive and autonomic nervous systems in people with knee OA and FM, compared to pain-free controls. Methods: A cross-sectional study was undertaken with 14 people with knee OA, 13 people with FM, and 15 pain free controls. Across two experimental sessions, baseline recordings and the response of the nociceptive and autonomic nervous systems to a 5-min submaximal isometric contraction of the quadriceps muscle was assessed. The nociceptive system was assessed using pressure pain thresholds at the knee and forearm. The ANS was assessed using high frequency heart rate variability, cardiac pre-ejection period, and electrodermal activity. Outcome measures were obtained before and during (ANS) or immediately after (nociceptive) the acute bout of exercise. Results: Submaximal isometric exercise led to EIH in the control group. EIH was absent in both chronic pain groups. Both chronic pain groups showed lower vagal activity at rest. Furthermore, people with knee OA demonstrated reduced vagal withdrawal in response to acute isometric exercise compared to controls. Sympathetic reactivity was similar across groups. Discussion: The findings of reduced tonic vagal activity and reduced autonomic modulation in response to isometric exercise raise the potential of a blunted ability to adapt to acute exercise stress and modulate nociception in people with knee OA. The impairment of EIH in knee OA may, in part, be due to ANS dysfunction.

Impact of preoperative exercise in not initially candidates to native arteriovenous fistulas.

BACKGROUND: Native autologous arteriovenous fistula (AVFn) is the preferred vascular access for hemodialysis due to its long term patency and low complication rate. A challenging limitation is the anatomical inability to perform AVFn and failure of maturation. Preoperative isometric exercise (PIE) can increase vascular calibers and improve the rate of distal AVF. However, it is unknown whether PIE might enhance the performance of AVFn in patients who are not initially candidates. METHODS: A retrospective observational study was conducted over a population of 45 patients evaluated in vascular access clinic, 23 were not initially candidates for radiocephalic (NRC-AVF) and 22 were not candidates for autologous fistula at all (NA-AVF). They were assigned to perform PIE with handgrip device and revaluated. RESULTS: After 4-8 weeks of PIE, a AVFn was performed in 16 patients from NA-AVF group and a radiocephalic AVFn was performed in 21 patients from NRC-AVF group. Both groups experienced a significant and similar increase in venous caliber 0.91 ± 0.43 mm in NA-AVF versus 0.76 ± 0.47 mm in NRC-AVF (p = 0.336) and arterial caliber 0.18 ± 0.24 mm versus 0.18 ± 0.21 mm (p = 0.928), respectively. Nevertheless, primary failure rate was significantly higher in NA-AVF (n = 8, 50%) than in NRC-AVF group (n = 3, 14.3%) (p = 0.030). After 6 months, the fistula usability for dialysis was only 50% in NA-AVF, while 86.7% were dialyzed by fistula in NRC-AVF group (p = 0.038). CONCLUSIONS: PIE allowed the allocation of an AVFn in patients not initially candidates, but entailed a high rate of maturation failure. Patients not candidates to radiocephalic AVF benefited from PIE and preserved a long term usability of AVF for dialysis.

Effects of different exercises on respiratory parameters: A randomized controlled trial.

This study was designed to compare the effects of core stabilisation (CS) and auxiliary respiratory muscle strengthening exercises on oxygen consumption and respiratory parameters. A total of 51 participants were divided into three groups with block randomization method according to age and gender: CS Group (n = 17), Auxiliary Respiratory Muscles Exercise (ARM) Group (n = 17) and Control (C) Group (n = 17). Maximum oxygen uptake (VO2 max), first second of forced expiration (FEV1)/Forced vital capacity (FVC) and maximal voluntary ventilation (MVV) values were evaluated before and after the study. CS and ARM strengthening exercises were applied 3 days a week for 6 weeks. The increase in the FEV1/VC values was higher in the CS and ARM groups than in the C group (p < 0.05), whereas no statistically significant difference was observed between the ARM and CS groups (p < 0.05). There was no statistically significant difference between the groups in terms of VO2 max values before and after the study (p > 0.05). The increase in the MVV values was higher in the CS and ARM groups than in the C group (p < 0.05), whereas no statistically significant difference was observed between the ARM and CS groups (p > 0.05). CS and ARM exercises had positive effects on FEV1/FVC and MVV.

Myocardial performance index as a measure of global left ventricular function improves following isometric exercise training in hypertensive patients.

As the leading cause of cardiovascular disease and mortality, hypertension remains a global health problem. Isometric exercise training (IET) has been established as efficacious in reducing resting blood pressure (BP); however, no research to date has investigated its effects on the myocardial performance index (MPI). Twenty-four unmedicated hypertensive patients were randomized to 4 weeks of IET and a control period in a crossover design. Tissue Doppler imaging was used to acquire cardiac time intervals pre- and post-IET and during the control periods. IET significantly improved all measures of cardiac time intervals, including isovolumic relaxation time (83.1 ± 10.3 vs. 76.1 ± 11.2 ms, p = 0.006), isovolumic contraction time (84.8 ± 10.3 vs. 72.8 ± 6.4 ms, p < 0.001), ejection time (304.6 ± 30.2 vs. 321.4 ± 20.8 ms, p = 0.015) and the MPI (0.56 ± 0.09 vs. 0.47 ± 0.05, p < 0.001). This is the first study to demonstrate that IET significantly improves cardiac time intervals. These findings may have important clinical implications, highlighting the potential utility of IET in the management of cardiac health in hypertensive patients.

Impact of Isometric Exercise in Adolescents With End Stage Kidney Disease and Unsuitable Vessels For An Autologous Arteriovenous Fistula.

INTRODUCTION: Despite the lack of calcification, to perform a native Arteriovenous Fistula (AVF) in young patients may pose a challenge due to small vessel diameter. We report a case series with no options of AVF in which vessel caliber improvement after isometric exercise allowed for radiocephalic fistula creation in all of them. METHODS: Since 2017 to 2019, four patients were referred to our unit to create an AVF. Following a first assessment with physical examination and doppler ultrasound, none of them were eligible for AVF performance due to small vessel caliber. Once they were considered unsuitable for it, they started an isometric exercise program. RESULTS: Age ranged from 13 to 19 years. There were three males and one female. Two were in predialysis and two in hemodialysis program. Initial diameters of the forearm cephalic vein and the radial artery respectively were: case A < 1.5/2.3 mm, case B 1.5/1.6 mm, case C < 1.5/1.6 mm and case D 2.1/1.3 mm. Median duration of exercise program was 13 weeks (range 5-23). Post-exercise vessel diameters were: case A 2.7/2.3 mm, case B 2.5/2 mm, case C 2.8/1.8 mm and case D 2.7/2 mm. Radiocephalic AVF were performed in the four cases. After a median follow up of 19 months (range 9-30 months), 75% of patients required further interventions but all of them had a functional AVF. CONCLUSIONS: In these four cases isometric preoperative exercise allowed the creation of AVF. Without the improvement in vessel diameter observed afterwards, all of them would have been rejected for AVF performance. Despite the high rate of adjunctive interventions needed, given the safety of the program and the potential risks of Central Venous Catheters, we consider it a valuable option.

Superisometric aquatic training in the physical preparation of soccer players / Treinamento aquático superisométrico no preparo físico de futebolistas / Entrenamiento acuático superisométrico en la preparación física de futbolistas

ABSTRACT Introduction: With the growing importance of physical training over sport training for competition, more research has been conducted. One of the least explored techniques is superisometric aquatic training. Objective: Study the application of super-isometric aquatic training to the physical training of soccer athletes. Methods: A literature review was performed to elaborate an experimental protocol. The experimental method was conducted on 24 university volunteers randomly divided into control and experimental groups. Classical training was conducted for two weeks between the groups, superisometric aquatic training was added only in the experimental group. Through the mathematical-statistical method, a comparative analysis of the research results was elaborated, and the effects of the intervention were discussed. Results: The movement time of the athletes in the experimental training group was reduced by 1.89s. The performance of running, tapping, standing jump, and weightlifting tests is not significantly different from those of the traditional strength training group. Conclusion: The application of superisometric aquatic training in the physical preparation of soccer players increased the overall strength of athletes,and also beneficially influenced specific activities of the sport. It is recommended to analyze the characteristics of the athlete and integrate superisometric training to general strength traispecificcally to the need of each athlete. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: Com a crescente importância do treinamento físico sobre o treinamento esportivo para competição, um número cada vez maior de pesquisas vem sendo realizado. Uma das técnicas pouco exploradas é o treinamento aquático superisométrico. Objetivo: Estudar a aplicação do treinamento aquático superisométrico ao treinamento físico de preparo dos atletas de futebol. Métodos: Uma análise da literatura foi efetuada para elaborar um protocolo experimental. O método experimental foi conduzido sobre 24 universitários voluntários divididos aleatoriamente em grupo controle e experimental. O treinamento clássico foi conduzido por duas semanas entre os grupos, o treinamento aquático superisométrico foi adicionado apenas no grupo experimental. Através do método estatístico matemático uma análise comparativa dos resultados da pesquisa foi elaborada e os efeitos da intervenção foram discutidos. Resultados: O tempo de movimento dos atletas no grupo de treinamento experimental foi reduzido em 1,89s. O desempenho de corrida, toque, salto em pé e os resultados dos testes de levantamento de peso não foram significativamente diferentes daqueles do grupo de treinamento de força tradicional. Conclusão: A aplicação do treinamento aquático superisométrico no preparo físico de futebolistas aumentou a força geral dos atletas, também influenciou beneficamente em atividades específicas do esporte. Recomenda-se analisar as características do esportista e integrar o treinamento superisométrico ao treinamento de força geral especificamente à necessidade de cada esportista. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: Con la creciente importancia de la preparación física en el entrenamiento deportivo para la competición, se ha realizado un número cada vez mayor de investigaciones. Una de las técnicas poco exploradas es el entrenamiento acuático superisométrico. Objetivo: Estudiar la aplicación del entrenamiento acuático superisométrico a la preparación física de los deportistas de fútbol. Métodos: Se realizó una revisión de la literatura para elaborar un protocolo experimental. El método experimental se llevó a cabo con 24 voluntarios universitarios divididos aleatoriamente en grupos de control y experimentales. El entrenamiento clásico se realizó durante quince días entre los grupos, el entrenamiento acuático superisométrico se añadió sólo en el grupo experimental. Mediante el método estadístico matemático se elaboró un análisis comparativo de los resultados de la investigación y se discutieron los efectos de la intervención. Resultados: El tiempo de movimiento de los atletas del grupo de entrenamiento experimental se redujo en 1,89s. El rendimiento de la carrera, el golpeo, el salto de pie y los resultados de las pruebas de levantamiento de pesas no fueron significativamente diferentes de los del grupo de entrenamiento de fuerza tradicional. Conclusión: La aplicación del entrenamiento acuático superisométrico en la preparación física de los jugadores de fútbol aumentó la fuerza general de los atletas, también influyó beneficiosamente en las actividades específicas del deporte. Se recomienda analizar las características del deportista e integrar el entrenamiento superisométrico al entrenamiento de fuerza general de forma específica a la necesidad de cada deportista. Nivel de evidencia II; Estudios terapéuticos -investigación de los resultados del tratamiento.

Comparison of time-dependent resistance isometric exercise and active range of motion exercise in alleviating the sensitization of postoperative axial pain after cervical laminoplasty.

BACKGROUND: Postoperative axial pain (PAP) is a significant complication after cervical laminoplasty. OBJECTIVE: To investigate pain sensitization in PAP patients and effects of time-dependent resistance isometric exercise compared to active range-of-motion exercise on PAP. STUDY DESIGN: Retrospective cohort analysis. METHODS: 211 patients undergoing postoperative 12-week exercises were evaluated for pressure pain threshold (PPT), temporal summation (TS) and both cross-sectional area and fatty infiltration of paraspinal muscles preoperatively and 3 months postoperatively. There patients underwent Numeric rating pain scale (NRS) and neck disability index (NDI) 3 and 6 months postoperatively. RESULTS: At postoperative 3-month assessments, fewer patients undergoing isometric exercise showed PAP compared to range-of-motion exercise group (14/98 vs. 34/113; P = 0.006), and pain-related assessments in the former were lower than the latter (NRS at rest: 0.3 ± 0.8 vs. 0.7 ± 1.4, P = 0.014; NRS with movements: 0.4 ± 1.0 vs. 1.0 ± 1.7, P = 0.015; NDI: 2.4 ± 6.3 vs. 6.7 ± 10.9, P = 0.002). Postoperative cross-sectional area was smaller in isometric exercise group (603.5 ± 190.2) than in range-of-motion exercise group (678.7 ± 215.5) (P = 0.033), and the former showed higher local-area PPT and lower TS than the latter (PPT: 3.9 ± 1.8 vs. 3.1 ± 1.6, P = 0.002; TS: 1.8 ± 0.9 vs. 2.2 ± 1.0, P = 0.003). PAP patients showed lower local-area PPT and greater TS than those without PAP in both isometric (PPT: 2.8 ± 0.7 vs. 4.0 ± 1.9, P = 0.019; TS: 2.4 ± 0.6 vs. 1.7 ± 0.9, P = 0.011) and range-of-motion (PPT: 2.2 ± 0.9 vs. 3.6 ± 1.7, P < 0.001; TS: 2.8 ± 0.8 vs. 1.9 ± 0.9, P < 0.001) exercise groups. CONCLUSIONS: Both peripheral and central sensitization are involved in PAP. Time-dependent isometric exercise has more positive effects on PAP than range-of-motion exercise because of its advantages in improving pain sensitization.

Acute effect of auxotonic and isometric contraction evaluated by infrared thermography in handball players.

The Infrared Thermography (IRT) is being used in the field of sport as a means of quantifying the effects of workload. The aims of this study were (i) to determine the variations in skin temperature (Tsk) of the lower limbs after an effort of auxotonic and isometric squat contractions using infrared thermography and (ii) to study jumping performance variations in handball players after those two different contraction types. A total of 15 national level handball players voluntarily participated in the study (age: 23.20 ± 5.23 years). Two types of protocols - isometric and auxotonic - were performed on different days, having previously calculated the maximal isometric squat strength and auxotonic 1RM. During the data collection, participants performed a specific standardized warm-up and then randomly performed 4x10 repetitions of auxotonic squat to 90° of knee flexion at 70% of 1RM and 4x10 s of isometric squat effort at 90° of knee flexion, at 70% of maximal isometric squat strength (both with a passive recovery of 90 s seated). Rate of perceived exertion (RPE) and countermovement jumping performance (CMJ) were measured before and immediately after efforts. Additionally, infrared thermography data from twelve regions of interest of the lower limbs were registered before, immediately after and 15 min after finishing the effort. The main results indicated no significant differences for RPE (p = 0.486), CMJ vertical height (VH; p = 0.344) and Tsk (p > 0.05) in any of the regions of interest after protocols. Significant differences (p < 0.05) were found for the time of data collection on Tsk with similar pre- and post-15 min values. In conclusion, Tsk decreased after both isometric and auxotonic effort at 70% of the maximal performance and recovered baseline values within 15 min of completion. Both efforts produced similar effects on skin temperature and did not affect jumping performance after exercise.

Isometric handgrip exercise impacts only on very short-term blood pressure variability, but not on short-term blood pressure variability in hypertensive individuals: A randomized controlled trial.

Background: The effect of a single isometric handgrip exercise (IHG) on blood pressure (BP) variability (BPV) has not been addressed. This randomized controlled trial evaluated the effect of IHG vs. sham on BPV and BP. Methods: Hypertensive patients using up to two BP-lowering medications were randomly assigned to IHG (4 × 2 min; 30% of maximal voluntary contraction, MVC, with 1 min rest between sets, unilateral) or sham (protocol; 0.3% of MVC). Systolic and diastolic BP were assessed beat-to-beat in the laboratory before, during, and post-intervention and also using 24-h ambulatory BP monitoring (ABPM). BPV was expressed as average real variability (ARV) and standard deviation (SD). Results: Laboratory BPV, ARV and SD variability, had marked increase during the intervention, but not in the sham group, decreasing in the post-intervention recovery period. The overall change in ARV from pre- to 15 min post-intervention were 0.27 ± 0.07 (IHG) vs. 0.05 ± 0.15 (sham group), with a statistically significant p-value for interaction. Similarly, mean systolic BP increased during the intervention (IHG 165.4 ± 4.5 vs. sham 152.4 ± 3.5 mmHg; p = 0.02) as did diastolic BP (104.0 ± 2.5 vs. 90.5 ± 1.7 mmHg, respectively; p < 0.001) and decreased afterward. However, neither the short-term BPV nor BP assessed by ABPM reached statistically significant differences between groups. Conclusion: A single session of IHG reduces very short-term variability but does not affect short-term variability. IHG promotes PEH in the laboratory, but does not sustain 24-h systolic and diastolic PEH beyond the recovery period.