Predictive Model of All-Cause Death in Patients with Heart Failure using Heart Rate Variability.

Background: Central Illustration : Predictive Model of All-Cause Death in Patients with Heart Failure using Heart Rate Variability.

Background: Short and long-duration heart rate variability (HRV) data from Holter monitoring could identify predictors of all-cause death in heart failure (HF) patients.

Objectives: To build a predictive model of all-cause death in patients with HF using HRV.

Do exist differences in kinematics and EMG of the hip and knee between male runners with and without patellofemoral pain in different running speeds?

Objective: Patellofemoral pain (PFP) presents a higher prevalence in female runners, while PFP in male is somehow neglected. Moreover, the effects of progressive greater running speed have not been reported. This study investigates the influence of progressive greater running speed on lower limb tridimensional kinematics and muscle activation (EMG) in male runners with PFP while compared with controls.

Biomechanical and Anthropometric Factors That Differentiate National- and Regional-Level Judo Players.

Purpose: The study aimed to identify the variables that differentiate judo athletes at national and regional levels. Multivariable analysis was applied to biomechanical, anthropometric, and Special Judo Fitness Test (SJFT) data.

Method: Forty-two male judo athletes from 2 competitive groups (14 national and 28 state levels) performed the following measurements and tests: (1) skinfold thickness, (2) circumference, (3) bone width, (4) longitudinal length, (5) stabilometric tests, (6) dynamometric tests, and (7) SJFT.

Fractal Brownian Motion Assessment of the Center of Pressure Excursion During Impulse Phase on Standard Vertical Jump.

This study presents and applies fractal Brownian motion assessment of the center of pressure (COP) excursion during feet ground contact on standard vertical jump impulse phase with long and short countermovement (CM) in relation with lower limb muscle stretch-shortening cycle (SSC) comparing it with no CM and SSC. Fifty-four tests were performed by a group of six healthy male students of sports and physical education degree without previous injury, specific training, or fitness ability. Three repetitions were performed by each subject of a squat jump (SJ) without CM and SSC, countermovement jump (CMJ) with long CM and SSC, as well as drop jump (DJ) with short CM and SSC after depth jump from a 40 cm step.

A telediagnosis assistance system for multiple-lead electrocardiography.

The diffusion of telemedicine opens-up a new perspective for the development of technologies furthered by Biomedical Engineering. In particular, herein we deal with those related to telediagnosis through multiple-lead electrocardiographic signals. This study focuses on the proof-of-concept of an internet-based telemedicine system as a use case that attests to the feasibility for the development, within the university environment, of techniques for remote processing of biomedical signals for adjustable detection of myocardial ischemia episodes.

Do hip strength, flexibility and running biomechanics predict dynamic valgus in female recreational runners?

Backgound: Dynamic valgus has been the focus of many studies to identify its association to an increased risk of running-related injuries. However, it is not known which physical and biomechanical variables are associated with this movement dysfunction.

Research Question: This study aimed to test the correlation between strength, flexibility and biomechanical variables and dynamic valgus in female runners.

Assessing Dynamic Atrioventricular Conduction Time to RR-interval Coupling in Athletes and Sedentary Subjects.

Background Atrioventricular conduction time ( AVCT ) is influenced by autonomic input and subject to physiological remodeling. Objective To evaluate beat-by-beat AVCT and RR-interval variability in athletes and healthy sedentary subjects. Methods Twenty adults, including 10 healthy sedentary (Controls) and 10 elite long-distance runners (Athletes), age, weight and height-adjusted, underwent maximal metabolic equivalent (MET) assessment, and 15-min supine resting ECG recording seven days later.

Association between circadian Holter ECG changes and sudden cardiac death in patients with Chagas heart disease.

Objective: Chagas disease (ChD) is a parasitic illness, largely spread over South America. ChD usually causes progressive myocardium damage, either by direct parasite action or through autoimmune response. Sudden cardiac death (SCD) is prevalent in the early disease stages, being associated with a high variety of ectopic cardiac beats.

Generalized Lower Limb Joint Angular Phase Space Analysis of Subject Specific Normal and Modified Gait.

This study presents and applies generalized angular phase space analysis to lower limb joint angles of specific subject during normal and modified gait for discrimination of gait and joint angular movements. Case study of an adult healthy male in-vivo and noninvasive kinematic assessment of skin surface adhesive markers at lower limb was performed at human movement lab during normal gait, stiff knee gait and slow running. Musculoskeletal modeling was performed using AnyGait v.

Prediction of mild anatomical leg length discrepancy based on gait kinematics and linear regression model.

Backgound: Leg length discrepancy (LLD) can be related to different pathologies, due to an inadequate distribution of mechanical loads, as well as gait kinematics asymmetries resulted from LLD.

Research Question: To validate a model to predict anatomical LLD (ALLD) based on gait kinematics.

Methods: Gait of 39 participants with different lower limb pathologies and mild discrepancy were collected.

Accuracy of the WHO's body mass index cut-off points to measure gender- and age-specific obesity in middle-aged adults living in the city of Rio de Janeiro, Brazil.

Introduction: Obesity is defined by the World Health Organization (WHO) as a disease characterized by the excessive accumulation of body fat. Obesity is considered a public health problem, leading to serious social, psychological and physical problems. However, the appropriate cut-off point of body mass index (BMI) based on body fat percentage (BF%) for classifying an individual as obese in middle-aged adults living in Rio de Janeiro remains unclear.

Consistency of surface electromyography assessment at lower limb selected muscles during vertical countermovement.

Given the difficulty of invasive methods to assess muscle action during natural human movement, surface electromyography (sEMG) has been increasingly used to capture muscle activity in relation to kinesiological analysis of specific tasks. Isolated isometric, concentric and eccentric forms of muscle action have been receiving the most attention for research purposes. Nevertheless natural muscle action frequently involves the use of a preceding eccentric muscle action as a form of potentiation of immediate muscle concentric action, in what is designated as muscle stretch-shortening cycle (SSC).

Effect of Resistance Training on Blood Pressure and Autonomic Responses in Treated Hypertensives.

Trevizani, GA, Seixas, MB, Benchimol-Barbosa, PR, Vianna, JM, da Silva, LP, and Nadal, J. Effect of resistance training on blood pressure and autonomic responses in treated hypertensives. J Strength Cond Res 32(5): 1462-1470, 2018-This study evaluated the effect of resistance training (RT) on heart rate variability (HRV) and on blood pressure (BP) responses to acute and short-term exposure in treated hypertensive (HT) subjects.

Crossover assessment of cardiolocomotor synchronization during running.

Purpose: This study aimed at testing the hypothesis that positive cardiolocomotor coordination (CLC) measure occurs by chance during a running task where the heart rate (HR) is approximated to the step frequency (StepF).

Methods: The electrocardiogram and electromyogram from the right gastrocnemius lateralis muscle were continuously recorded from ten healthy young men running at a paced rhythm of 152 step/min, to monitor HR and StepF. CLC was evaluated by phase synchrograms and the index of conditional probability (iCP).

Muscle Fatigue Assessment During Cycle Ergometer Exercise Using Principal Component Analysis of Electromyogram Power Spectra.

During muscle fatigue analysis some standard indexes are calculated from the surface electromyogram (EMG) as root mean square value (RMS), mean (F), and median power frequency (F). However, these parameters present limitations and principal component analysis (PCA) appears to be an adequate alternative. In this context, we propose two indexes based on PCA to enhance the quantitative muscle fatigue analysis during cyclical contractions.

Residual analysis of ground reaction forces simulation during gait using neural networks with different configurations.

The aim of the study was to analyze and compare the residuals obtained from ground reaction force (GRF) models developed using two different neural network configurations (one network with three outputs; and three networks with one output each), based on accelerometer data. Seventeen healthy subjects walked along a walkway, with a force plate embedded, with a three dimensional accelerometer attached to the shank. Multilayer perceptron networks (MLP) models were developed with the 3D accelerometer data as inputs to predict the GRF.

Cardiac autonomic responses after resistance exercise in treated hypertensive subjects.

The aim of this study was to assess and to compare heart rate variability (HRV) after resistance exercise (RE) in treated hypertensive and normotensive subjects. Nine hypertensive men [HT: 58.0 ± 7.

Lumbar multifidus and erector spinae electromyograms during back bridge exercise in time and frequency domains.

Background: Muscle activity is studied during trunk stabilization exercises using electromyograms (EMG) in time domain. However, the frequency domain analysis provides information that would be important to understand fatigue process.

Objective: To assess EMG of lumbar multifidus (LM) and erector spinae (ES) muscles, in time and frequency domains, during back bridge exercise.

Assessment of Autonomic Function by Phase Rectification of RRInterval Histogram Analysis in Chagas Disease.

Background: In chronic Chagas disease (ChD), impairment of cardiac autonomic function bears prognostic implications. Phase‑rectification of RR-interval series isolates the sympathetic, acceleration phase (AC) and parasympathetic, deceleration phase (DC) influences on cardiac autonomic modulation.

Objective: This study investigated heart rate variability (HRV) as a function of RR-interval to assess autonomic function in healthy and ChD subjects.

Cardiac autonomic changes in middle-aged women: identification based on principal component analysis.

The purpose of this study was to investigate the application of the principal component analysis (PCA) technique on power spectral density function (PSD) of consecutive normal RR intervals (iRR) aiming at assessing its ability to discriminate healthy women according to age groups: young group (20-25 year-old) and middle-aged group (40-60 year-old). Thirty healthy and non-smoking female volunteers were investigated (13 young [mean ± SD (median): 22·8 ± 0·9 years (23·0)] and 17 Middle-aged [51·7 ± 5·3 years (50·0)]). The iRR sequence was collected during ten minutes, breathing spontaneously, in supine position and in the morning, using a heart rate monitor.

Refining the deceleration capacity index in phase-rectified signal averaging to assess physical conditioning level.

Background: Deceleration capacity (DC) of heart rate is a measure of cardiac vagal modulation. This study introduced a DC adaptation (Modified Index) that measured the velocity of change in the phase-rectified signal averaging curve, and assessed its ability to discriminate athletes from controls.

Materials And Methods: The Modified Index was compared to Standard DC approach in a prospective case-control study.

Motor coordination during gait after anterior cruciate ligament injury: a systematic review of the literature.

To investigate the state of art about motor coordination during gait in patients with anterior cruciate ligament (ACL) injury. Searches were carried out, limited from 1980 to 2010, in various databases with keywords related to motor coordination, gait and ACL injury. From the analysis of titles and applying the inclusion/exclusion criteria 24 studies were initially selected and, after reading the abstract, eight studies remained in the final analysis.

Reducing cross terms effects in the Choi-Williams transform of mioelectric signals.

This study aims at investigating the effect of removing the negative values of Choi-Wiliams distribution (CWD) related to the electromyogram (EMG) for visualization and instantaneous median frequency (IMF) estimation. Beyond the EMG signals from triceps surae and biceps brachialis, the CWD was applied in a simulated sinusoidal signal as like in stationary and non-stationary simulated EMG signals (SES). The CWD negative values of all simulated and EMG signals were removed.

Classification of gait kinematics of anterior cruciate ligament reconstructed subjects using principal component analysis and regressions modelling.

The aim of this study was to compare the knee kinematics of anterior cruciate ligament reconstructed (ACL-R) and healthy subjects (CG) during gait and classify the status of normality. Ten healthy and six ACL-R subjects had their gait analyzed at 60 fps. 3D knee angles were calculated and inserted into three separate matrices used to perform the principal component (PC) analysis.

Role of vestibular sensor on body sway control: coherence between head acceleration and stabilogram.

This work aims at evaluating the role of the vestibular system in the postural sway control using the coherence function. A sample of 19 young, healthy male adults was monitored with a three axial accelerometer placed over the head during a stabilometric test, standing on a force platform during 3 min in four conditions: eyes closed and open, and feet apart and together. The magnitude squared coherence (MSC) function and Monte Carlo simulation was used to correlate changes in body sway with head accelerations.