Neural Adjustments during Repeated Braking and Throttle Actions on a Motorcycle Setup.

The aim of the study was to assess neuromuscular changes during an intermittent fatiguing task designed to replicate fundamental actions and ergonomics of road race motorcycling. Twenty-eight participants repeated a sequence of submaximal brake-pulling and gas throttle actions, interspaced by one maximal brake-pulling, until failure. During the submaximal brake-pulling actions performed at 30% MVC, force fluctuations, surface EMG, maximal M-wave (Mmax) and H-reflex were measured in the flexor digitorum superficialis. At the end of the task, the MVC force and associated EMG activity decreased (P<0.001) by 46% and 26%, respectively. During the task, force fluctuation and EMG activity increased gradually (106% and 61%, respectively) with respect to the pre-fatigue state (P≤0.029). The Mmax first phase did not change (P≥0.524), whereas the H-reflex amplitude, normalized to Mmax, increased (149%; P≤0.039). Noteworthy, the relative increase in H-reflex amplitude was correlated with the increase in EMG activity during the task (r=0.63; P<0.001). During the 10-min recovery, MVC force and EMG activity remained depressed (P≤0.05) whereas H-reflex amplitude and force fluctuation returned to pre-fatigue values. In conclusion, contrarily to other studies, our results bring forward that when mimicking motorcycling brake-pulling and gas throttle actions, supraspinal neural mechanisms primarily limit the duration of the performance.

Benefits of Training the Iron Cross With Herdos Devices and External Load Added to Body Weight for Young Nonachiever Gymnasts.

PURPOSE: To verify whether training the iron cross (IC) with assistive devices (herdos; HIC) and added external load (LHIC) to equate the moments of force developed on the rings could be considered an intermediate step between the nonoverloaded herdos situation (HIC) and the IC performed on the rings. METHODS: Relative levels of surface electromyography (sEMG) activity were normalized with respect to a standing IC before comparing gymnasts who can perform the IC on the rings (achievers) and gymnast who cannot (nonachievers) in the 2 herdos conditions (HIC and LHIC). Seven muscles were chosen for sEMG analysis, namely, pectoralis major (PM), latissimus dorsi, teres major, lower trapezius, serratus anterior, biceps brachii (BB), and triceps brachii. Additionally, 3 indices were calculated to measure levels of coactivation: Elbowidx, Scapulaidx, and Shoulderidx. RESULTS: The bigger magnitude of differences in sEMG activity among situations was found for the PM and BB (F ≥ 30.7; P < .001). When comparing the global and the PM, teres major, BB, and triceps brachii activity across groups, nonachievers activated their musculature to a greater extent than the achievers independently of the herdos situation (P ≤ .046). Achievers' Elbowidx was the only index that was significantly higher (P ≤ .005) in the IC in comparison to LHIC and HIC. CONCLUSION: sEMG activity of PM and BB was particularly sensitive between situations, independently of the level of achievement. We recommend training the IC by adding external load in the herdos situation to increase muscle activity to levels closer to the rings situation but avoiding the potential factor of injuries.

Exploring forearm muscle coordination and training applications of various grip positions during maximal isometric finger dead-hangs in rock climbers.

Background: Maximal isometric finger dead-hangs are used in rock climbing to strengthen finger flexors. Although various grip positions are often used when performing finger dead-hangs, little is known regarding how these grip positions can affect forearm muscle activity. Understanding how forearm muscles are recruited during dead-hangs could help foreseeing the potential for training of different grip positions. The aim of the present study was to explore the training applications of the various grip positions by comparing the activity of forearm muscles during maximal dead-hangs in rock climbers. Materials & Methods: Twenty-five climbers performed maximal dead-hangs in three climbing-specific grip positions: CRIMP, SLOPE, and SLOPER. We recorded the maximal loads used and the sEMG of the flexor digitorum profundus (FDP), the flexor digitorum superficialis (FDS), the flexor carpi radialis (FCR), and the extensor digitorum communis (EDC). Individual and global (sum of all muscles) root mean square (RMS) and neuromuscular efficiency (NME) values were computed. Repeated measures analysis were performed to assess grip differences (p < 0.05). Results: SLOPER showed the largest maximal load values among the three grip positions (p < 0.001, d ≥ 2.772). Greater global (p ≤ 0.044, d ≥ 0.268), FDS (p ≤ 0.005, d ≥ 0.277), and FCR (p < 0.001, d ≥ 1.049) activity was observed for the SLOPER compared to CRIMP and SLOPE, while EDC (p ≤ 0.005, d ≥ 0.505) showed lower activity in the SLOPER compared to the other two grip positions. SLOPER presented the highest global (p < 0.001, d ≥ 0.629), FDP (p < 0.001, d ≥ 0.777), FDS (only CRIMP vs SLOPER: p < 0.001, d = 0.140), and EDC NME (p < 0.001, d ≥ 1.194). The CRIMP showed greater FDS activity (p = 0.001, d = 0.386) and lower NME (p = 0.003, d = 0.125) compared to SLOPE. Conclusions: These results revealed that, under maximum intensity conditions, SLOPER could stimulate the FDS and FCR better than the other grip positions at the expense of using greater loads. Similarly, maximum CRIMP dead-hang could better stimulate the FDS than the SLOPE, even when using similar loads.

Exercise improves depression through positive modulation of brain-derived neurotrophic factor (BDNF). A review based on 100 manuscripts over 20 years.

The aim of this review was to explore the relevant neurobiology and the association between peripheral levels of brain-derived neurotrophic factor (BDNF) and acute and short to long-term exercise regimes, as well as its relation to depression and antidepressant treatment. A 20-year literature search was conducted. The screening process resulted in 100 manuscripts. Antidepressants as well as acute exercise, particularly high-intensity, elevates BDNF in healthy humans and clinical populations, as evidenced from aerobic and resistance-based studies. Although exercise is increasingly recognised in the management of depression, acute and short-term exercise studies have failed to establish a relationship between the severity of depression and changes in peripheral BDNF. The latter rapidly returns to baseline, possibly indicating a quick re-uptake by the brain, aiding its neuroplasticity functions. The timescale of administration needed for the antidepressants to stimulate biochemical changes is longer than similar increases with acute exercise.

Changes of agonist and synergist muscles activity during a sustained submaximal brake-pulling gesture.

We analyzed the time course of changes in muscle activity of the prime mover and synergist muscles during a sustained brake-pulling action and investigated the relationship between muscle activity and braking force fluctuation (FF). Thirty-two participants performed a continuous fatiguing protocol (CFP) at 30% of maximal voluntary contraction (MVC) until failure. Surface electromyography was used to analyze root mean square (RMS) values in the flexor digitorum superficialis (FD), flexor carpi radialis (FC), extensor digitorum communis (ED), extensor carpi radialis (EC), brachioradialis (BR), biceps brachii (BB), and triceps brachii (TB). The FF and RMS in all muscles increased progressively (P<0.01) during the CFP, with sharp increments at time limit particularly in FD and FC (P<0.001). The RMS of the FD and FC were comparable to the baseline MVC values at time limit, in comparison to the other muscles that did not reach such levels of activity (P<0.003). The three flexor/extensor ratios used to measure coactivation levels decreased significantly (P<0.001). In contrast to RMS, MVC was still depressed at the minute 10 of recovery. The results suggest that the time limit was mainly constrained by fatigue-related mechanisms of the FD and FC but not by those of other synergist and antagonist muscles.

Muscle Fatigue When Riding a Motorcycle: A Case Study.

This case study was conducted to assess muscle pattern, as measured by surface electromyography (sEMG), and its changes during a controlled superbike closed-road track training session. The sEMG signals were recorded unilaterally from biceps brachii (BB), triceps brachii (TB), anterior and posterior part of the deltoid (DA and DP respectively), flexor digitorum superficialis (FS), extensor carpi radialis (CR), extensor digitorum communis (ED) and pectoralis major (PM) during three rounds of 30 min. sEMG signals selected for analysis came from the beginning of the braking action to the way-out of the curves of interest. Considering the laps and rounds as a whole and focusing on the forearm muscles, ED was more systematically (84%) assigned to a state of fatigue than FS (44%) and CR (39%). On the opposite, the TB and DP muscles showed a predominant state of force increase (72%). Whereas the BB showed alternatively a state of fatigue or force increase depending on the side of the curve, when taking into account only the sharpest curves, it showed a predominant state of force increase. In conclusion, the fact that forearm muscles must endure a long-lasting maintenance of considerable activity levels explains why they easily got into a state of fatigue. Moreover, TB and DA are particularly relevant when cornering.

Recovery and Fatigue Behavior of Forearm Muscles during a Repetitive Power Grip Gesture in Racing Motorcycle Riders.

Despite a reduction in the maximal voluntary isometric contraction (MVCisom) observed systematically in intermittent fatigue protocols (IFP), decrements of the median frequency, assessed by surface electromyography (sEMG), has not been consistently verified. This study aimed to determine whether recovery periods of 60 s were too long to induce a reduction in the normalized median frequency (MFEMG) of the flexor digitorum superficialis and carpi radialis muscles. Twenty-one road racing motorcycle riders performed an IFP that simulated the posture and braking gesture on a motorcycle. The MVCisom was reduced by 53% (p < 0.001). A positive and significant relationship (p < 0.005) was found between MFEMG and duration of the fatiguing task when 5 s contractions at 30% MVCisom were interspersed by 5 s recovery in both muscles. In contrast, no relationship was found (p > 0.133) when 10 s contractions at 50% MVC were interspersed by 1 min recovery. Comparative analysis of variance (ANOVA) confirmed a decrement of MFEMG in the IFP at 30% MVCisom including short recovery periods with a duty cycle of 100% (5 s/5 s = 1), whereas no differences were observed in the IFP at 50% MVCisom and longer recovery periods, with a duty cycle of 16%. These findings show that recovery periods during IFP are more relevant than the intensity of MVCisom. Thus, we recommend the use of short recovery periods between 5 and 10 s after submaximal muscle contractions for specific forearm muscle training and testing purposes in motorcycle riders.

The Neuromuscular Characteristics of Gymnasts' Jumps and Landings at Particular Stages of Sports Training.

Safe and proper landings are crucial elements of gymnastics events. Long-term training leads to specific neuromuscular adaptations which are yet to be explored in terms of gymnastic landings. The aim of the study was to assess differences in landings' neuromuscular characteristics between gymnasts at three subsequent gymnastic training stages and age-matched non-athletes. Forty-six gymnasts (G) and 58 controls (C) performed countermovement jumps on a force plate with simultaneous surface electromyography (SEMG) of lower body muscles, measured during the pre-(100 ms) and post-landing phase (0-100 and 0-200 ms). Three age groups participated in the study: 8-10 (G1, C1), 12-14 (G2, C2), 18-25 (G3, C3) years. Analysis included the normalized root mean square (NRMS) SEMG signal and ground reaction forces (GRFs). Gymnasts achieved 13% higher values (p = 0.04) of relative peak GRFs in comparison with controls. It was especially seen in 8-10-year-olds: G1 presented 33% higher (p = 0.03) results than C1 and G2. In SEMG analysis, gymnasts showed overall lower NRMS values in comparison with the controls. In the pre-landing phase, the NRMS in the rectus femoris was from 1.6 up to 3.4 times higher for C1 (p = 0.02) than for C2, G2, C3, and G3. Gymnasts across subsequent training stages exhibit different patterns of neuromuscular coordination during landings. The highest GRF observed in the youngest gymnasts may be a potential risk factor of injuries. Therefore, further injury-focused investigation is recommended to monitor landing strategies among gymnasts of different stages with particular emphasis on the beginners.

Forearm muscles fatigue induced by repetitive braking on a motorcycle is best discriminated by specific kinetic parameters.

Maneuvering a motorcycle in racing conditions or for prolonged time is sufficiently demanding that on many occasions forearm muscles reach a state of functional failure when riders cannot properly brake or operate the throttle. This study intends to discriminate which ones of the several dynamometric parameters used in the literature to characterize the Force-time (F-t) curve during voluntary contractions are more sensitive to neuromuscular fatigue in simulated motorcycle-riding conditions. Thirty-three adults performed an intermittent fatiguing protocol (IFP) that simulated the brake-pulling and throttle-twisting actions, by using a hydraulic system equipped with a pressure sensor. Sixty pressure-time (P-t) curve parameters, including the rate of pressure development (RPD) and area under the curve were measured to characterize the time course of the braking maximal voluntary contraction (MVC). Two types of variables were used to analyze the P-t curve: 1) Times interval (from 0 to 30-50-100-500-1000 and 2000 ms); 2) Percentages of MVC (10-30-60-90%MVC). Overall significant (p ≤ 0.05) fatigue-related declines were observed only at time intervals longer than 100 ms and contraction intensities higher than 30%MVC. Strong and significant linear declines (p < 0.001) were observed at 500 ms and 1 s for normalized pressures, as well as for the ratio RPD60%MVC/MVC (p < 0.003) throughout the IFP. Our results suggest considering RPD at time windows of 0-500 ms and 0-1 s, and contraction intensities comprised between 30% and 60% of MVC, as more suitable criteria to study fatigue-related decrements in performance rather than the classical MVC force.

Factores Pronóstico de Neumonía Grave Comunitaria en Unidad de Terapia Intensiva Pediátrica. Bayamo. 2016-2019 / Prognostic Factors for Severe Community Pneumonia in a Pediatric Intensive Care Unit. Bayamo. 2016-2019

Introducción: la neumonía adquirida en la comunidad (NAC) es una infección aguda del parénquima pulmonar que afecta a un paciente previamente sano o inmunocompetente expuesto a un microorganismo fuera del Hospital. Objetivo: determinar los principales factores pronósticos de mortalidad de la Neumonía grave adquirida en la comunidad, en pacientes ingresados con este diagnóstico en la UTIP de Bayamo, durante 2016-2019. Métodos: se realizó un estudio observacional analítico prospectivo, de cohorte transversal, para determinar los factores pronósticos asociados a la mortalidad por Neumonía grave comunitaria en la Unidad de Cuidados Intensivos (UTIP) en el Hospital Pediátrico Docente General Luís Ángel Milanés Tamayo de Bayamo, durante los años 2016-2019. Resultados: la presencia concomitante de Síndrome de Dificultad Respiratoria Aguda, sepsis y la edad menor de un año, resultaron factores favorecedores de muerte en pacientes con neumonía grave comunitaria. Conclusiones: la exposición de los pacientes a la asociación de los factores del modelo predictivo resultante, determinó una probabilidad de fallecer del 29 por ciento(AU)

Introduction: community acquired pneumonia (CAP) is an acute infection of the lung parenchyma that affects a previously healthy or immunocompetent patient exposed to a microorganism outside the Hospital. Objective: to determine the main prognostic factors for mortality of severe community-acquired pneumonia in patients admitted with this diagnosis to the Bayamo PICU, during 2016-2019. Methods: a prospective, analytical, observational, cross-sectional cohort study was carried out to determine the prognostic factors associated with mortality from severe community pneumonia in the Intensive Care Unit (PICU) at the General Luís Ángel Milanés Tamayo Pediatric Teaching Hospital in Bayamo, during the years 2016-2019. Results: the concomitant presence of Acute Respiratory Distress Syndrome, sepsis, and age less than one year, were factors favoring death in patients with severe community pneumonia. Conclusions: the exposure of the patients to the association of the factors of the resulting predictive model, determined a probability of death of 29 percent(EU)

Factores Pronóstico de Neumonía Grave Comunitaria en Unidad de Terapia Intensiva Pediátrica. Bayamo. 2016-2019 / Prognostic Factors for Severe Community Pneumonia in a Pediatric Intensive Care Unit. Bayamo. 2016-2019 / Fatores prognósticos para Pneumonia Comunitária Grave em Unidade de Terapia Intensiva Pediátrica. Bayamo. 2016-2019

RESUMEN Introducción: la neumonía adquirida en la comunidad (NAC) es una infección aguda del parénquima pulmonar que afecta a un paciente previamente sano o inmunocompetente expuesto a un microorganismo fuera del Hospital. Objetivo: determinar los principales factores pronóstico de mortalidad de la Neumonía grave adquirida en la comunidad, en pacientes ingresados con este diagnóstico en la UTIP de Bayamo, durante 2016-2019. Métodos: se realizó un estudio observacional analítico prospectivo, de cohorte transversal, para determinar los factores pronóstico asociados a la mortalidad por Neumonía grave comunitaria en la Unidad de Cuidados Intensivos (UTIP) en el Hospital Pediátrico Docente General Luís Ángel Milanés Tamayo de Bayamo, durante los años 2016-2019. Resultados: la presencia concomitante de Síndrome de Dificultad Respiratoria Aguda, sepsis y la edad menor de un año, resultaron factores favorecedores de muerte en pacientes con neumonía grave comunitaria. Conclusiones: la exposición de los pacientes a la asociación de los factores del modelo predictivo resultante, determinó una probabilidad de fallecer del 29 %.

ABSTRACT Introduction: community acquired pneumonia (CAP) is an acute infection of the lung parenchyma that affects a previously healthy or immunocompetent patient exposed to a microorganism outside the Hospital. Objective: to determine the main prognostic factors for mortality of severe community-acquired pneumonia in patients admitted with this diagnosis to the Bayamo PICU, during 2016-2019. Methods: a prospective, analytical, observational, cross-sectional cohort study was carried out to determine the prognostic factors associated with mortality from severe community pneumonia in the Intensive Care Unit (PICU) at the General Luís Ángel Milanés Tamayo Pediatric Teaching Hospital in Bayamo, during the years 2016-2019. Results: the concomitant presence of Acute Respiratory Distress Syndrome, sepsis, and age less than one year, were factors favoring death in patients with severe community pneumonia. Conclusions: the exposure of the patients to the association of the factors of the resulting predictive model, determined a probability of death of 29%.

RESUMO Introdução: a pneumonia adquirida na comunidade (PAC) é uma infecção aguda do parênquima pulmonar que afeta um paciente previamente hígido ou imunocompetente exposto a um microrganismo fora do Hospital. Objetivo: determinar os principais fatores prognósticos de mortalidade por pneumonia grave adquirida na comunidade em pacientes admitidos com esse diagnóstico na UTIP Bayamo, durante o período de 2016-2019. Métodos: foi realizado um estudo de coorte prospectivo, analítico, observacional e transversal para determinar os fatores prognósticos associados à mortalidade por pneumonia comunitária grave na Unidade de Terapia Intensiva (UTIP) do Hospital Pediátrico General Luís Ángel Milanés Tamayo em Bayamo, durante os anos 2016-2019. Resultados: a presença concomitante de Síndrome do Desconforto Respiratório Agudo, sepse e idade inferior a um ano foram fatores que favoreceram o óbito em pacientes com pneumonia comunitária grave. Conclusões: a exposição dos pacientes à associação dos fatores do modelo preditivo resultante, determinou uma probabilidade de morte de 29%.

Salivary endocrine response following a maximal incremental cycling protocol with local vibration.

The aim of this study was to compare the effects of vibration (Vib versus noVib) during a maximal graded cycling exercise on hormonal response, precisely on cortisol (C) and testosterone (T). Twelve active males (25 ± 5yrs; 181 ± 5cm; 80.7 ± 11.1kg) randomly performed two maximal incremental cycling tests on two separate days and at the same time of the day (09:00). The protocol consisted of incremental steps of 3 min duration performed on a PowerBIKETM that induces vibration cycling. The study was a repeated measures design and participants performed the test with and without vibration. Gas exchange and heart rate (HR) were continuously assessed and blood lactate (Bla) was recorded at the end of each incremental stage. Saliva samples were collected before and immediately after the test, and analysed for (C) and (T). The results show that C and T increased in both cycling conditions; however, the C's magnitude of change was significantly higher by 83% after Vib cycling in comparison to the no Vib (p = 0.014), whereas the T's magnitude of change were not statistically different between trials (p = 0.715). Vibration induced a decrease of the T/C ratio (p = 0.046) but no significant changes were observed following noVib (p = 0.476). As a conclusion, the investigation suggests that adding mechanical vibration to cycling may potentiate a catabolic exercise-induced state, which could have potential clinical implications in rehabilitation and injury treatment. Sport experts should take this message home to carefully plan the recovery process and time during training and competitions.

Vibration Cycling Did Not Affect Energy Demands Compared to Normal Cycling During Maximal Graded Test.

The aim of this study was to compare the physiological responses between a vibration induced cycling step protocol (Vib) and normal cycling (without vibration, no-Vib). Eighteen moderate trained males (age 24.1 ± 4.3 years; weight 76.5 ± 10.5 kg; height 178.0 ± 6.4 cm) have participated in this study. They randomly performed two gradual maximal exercise tests on two separate days using a new bike that automatically induces vibration cycling and the Corival cycle ergometer. The choice of two different bikes was made because of the impossibility to recreate the same power output without altering the cycling cadence on the vibration Bike. Both protocols were matched for power output and cycling cadence incrementations. Oxygen uptake (VO2), carbon dioxide production (VCO2), ventilation (VE), heart rate (HR), blood lactate and rating of perceived exertion (RPE) during each stage were continuously recorded. No statistical differences were founded for all variables when comparing the Vib to no-Vib trials, except a higher ventilation during the vibration trial at submaximal levels. The results of this study do not confirm those of previous studies stated that Vib increased metabolic demands during cycling exercise. Added vibration stimulus to an incremental cycling protocol does not affect physiological parameters.

Changes in the Muscle Activity of Gymnasts During a Handstand on Various Apparatus.

Kochanowicz, A, Niespodzinski, B, Mieszkowski, J, Marina, M, Kochanowicz, K, and Zasada, M. Changes in the muscle activity of gymnasts during a handstand on various apparatus. J Strength Cond Res 33(6): 1609-1618, 2019-Gymnasts perform handstands on various apparatus, both in stable and unstable conditions. Such performances require specific muscle activation, which should differ depending on the condition and expertise of the gymnast. Therefore, the aim of the study was to evaluate (a) the difference in electromyography (EMG) between handstands performed on 3 apparatus (floor, rings, and parallel bars); and (b) the difference between young and well-trained adult gymnasts. Ten adult (25 ± 3.94 years) and 15 young (13.9 ± 0.7 years) gymnasts participated in the study. We investigated EMG amplitude in 13 muscles normalized by arbitrary angle maximal isometric voluntary contraction (normalized root mean square [NRMS]). In comparison with the handstand on the floor (61 ± 28%), the wrist flexor muscles of gymnasts exhibited a decreased NRMS on the parallel bars (44 ± 25%; p = 0.017), and rings (46 ± 32%; p = 0.029), whereas no changes were observed in the triceps brachii. The rest of the investigated muscles showed a higher NRMS in rings. Differences between young and adult gymnasts were seen in the triceps brachii and anterior deltoid muscles, where more experienced gymnasts showed 19.1% (p = 0.014) and 17.6% (p = 0.048) lower NRMS, respectively. The different gymnastic apparatus led to specific muscle activation. This activation predominantly depended on hand support conditions, which alternated the primary wrist strategy of the handstand balance control, and in consequence, the activation of other muscles controlling balance. Training focused on the development of motor control and strength of the anterior deltoid, pectoralis major, latissimus dorsi, biceps brachii, and trapezius descendens muscles to improve handstand performance.

Infección relacionada con los cuidados de la salud en Servicio de Clínicas Pediátricas. Bayamo. 2017 / Infection related to health care in Paediatric Clinic Service. Bayamo city. 2017

Las infecciones relacionadas con cuidados de la salud constituyen un importante problema sanitario. Con el objetivo de identificar las características clínicas y epidemiológicas de los pacientes con infección relacionada con los cuidados de la salud en niños ingresados en el Servicio de Clínicas Pediátricas del Hospital Infantil General Luis Ángel Milanés, se realizó un estudio descriptivo, retrospectivo, de corte transversal, en el periodo enero-diciembre del 2017. El universo agrupó los 5638 niños que ingresaron en el periodo de estudio y la muestra la conformaron los 45 que desarrollaron la infección. Se estudiaron variables: dependiente (infección asociada a cuidados sanitarios) e independientes (factores que incrementan la susceptibilidad a adquirir las mismas). Se emplearon los métodos de investigación teóricos, empíricos y estadísticos. Las medidas de resumen utilizadas fueron de la estadística descriptiva: frecuencias absolutas y relativas. Los cálculos se hicieron con el auxilio del programa estadístico profesional SPSS 22.0 para Windows. Como resultados más relevantes, la infección se desarrolló con mayor frecuencia en los niños menores de 1 año de edad (75,5 por ciento), en los que no recibieron lactancia materna exclusiva (55,5 por ciento) y en los que ingresaron en servicios hacinados (51,1 por ciento); la bacteriemia primaria (28,9 por ciento) y las infecciones respiratorias altas (24,4 por ciento) fueron las más frecuentes; existió predominio de los microorganismos grampositivos (58,9 por ciento). Se concluyó que la edad menor de un año, lactancia materna inadecuada y hacinamiento de los servicios de salud fueron las características más relevantes de los pacientes infectados(AU)

Infections related to health care constitute an important health problem. With the aim of identifying the clinical and epidemiological characteristics of patients with infection related to health care in children admitted to the Pediatric Clinics Service of the General Luis Ángel Milanés Children's Hospital, a descriptive, retrospective, cross-sectional study was carried out, in the period January-December 2017. The universe grouped 5638 children who entered the study period and the sample was made up of the 45 that developed the infection. Variables were studied: dependent (infection associated with health care) and independent (factors that increase the susceptibility to acquire them). Theoretical, empirical and statistical research methods were used. The summary measures used were descriptive statistics: absolute and relative frequencies. The calculations were made with the help of the professional statistical program SPSS 22.0 for Windows. As the most relevant results, infection developed more frequently in children under 1 year of age (75.5 percent), in those who did not receive exclusive breastfeeding (55.5 percent) and in those who were admitted to overcrowded services (51.1 percent); primary bacteraemia (28.9 percent) and upper respiratory infections (24.4 percent) were the most frequent; there was a predominance of gram-positive organisms (58.9 percent). It was concluded that age less than one year, inadequate breastfeeding and overcrowding of health services were the most relevant characteristics of infected patients(EU)

Age and gymnastic experience effects on sensory reweighting processes during quiet stand.

BACKGROUND: The relative contribution of sensory inputs to control balance while standing is dynamically adjusted. These sensory reweighting processes could be impacted by age and sport expertise capabilities, especially when the sport emphasizes equilibrium like artistic gymnastics. RESEARCH QUESTION: The aim of this study was to explore the sensory reweighting processes to adjust standing posture in children and adults with different gymnastic expertise (gymnasts, G, and non-gymnast, NG). METHODS: All participants were asked to stand quietly on a force plate in two visual conditions (eyes open, EO, and eyes closed, EC). Within a trial, proprioception was altered with two vibrators strapped at the Achilles tendon level. The center of pressure (COP) displacements in the anterior-posterior and medio-lateral directions were calculated and normalized by the base of support. The effect of vibration application was characterized by the COP speed, maximal posterior displacement and the time when it occurred. The effect of vibration removal was depicted by the time between the motor switched off and the achievement of balance values similar to baseline and the COP speed and movement units performed during this time. RESULTS: G children presented shorter posterior displacement during vibrations, needed less time to recover initial balance, and produced less movements units than NG children. In general, adults and EO showed better reweighting responses than children and EC, respectively. SIGNIFICANCE: These results suggest that age could have a positive effect on reweighting processes and that gymnastic experience may benefit the development of proprioceptive reweighting processes in children but not in adults.

Relationship between postural control and muscle activity during a handstand in young and adult gymnasts.

The aim of this study was to evaluate the relationship between muscle activity and inter-muscle contributions patterns and postural control during a handstand. Additionally, outcomes were compared between young and adult gymnasts (mean ±â€¯SD: 13.9 ±â€¯0.7 and 23 ±â€¯3 years respectively). Participants performed three trials of a 10 s handstand on a force platform with simultaneous EMG signal recording at the upper and lower limbs. Adult gymnasts demonstrated significantly better postural control in each studied variable. The wrist flexors demonstrated the highest relative mean (60%) and peak (200%) EMG activity of all muscle groups studied. Wrist flexor activity was also highly correlated with postural control variables in both groups. The trapezius descendens and wrist flexor muscles demonstrated the highest contribution (20-26% and 25.5-28% respectively), followed by anterior deltoid (15-18%) and triceps brachii (13-16%) in both groups. The young gymnast group demonstrated significantly greater mean relative muscle activity at the triceps brachii, biceps brachii and rectus femoris compared with the adult group (88% (p = 0.023), 150% (p = 0.003) and 75% (p = 0.039) respectively). To conclude, despite comparable inter-muscle contributions during a handstand, young and adult gymnasts demonstrated a different relationship between muscle activity and postural control variables.

Electromyographic and Kinematic Analysis of Trunk and Limb Muscles During a Holding Task in Individuals With Chronic Low Back Pain and Healthy Controls.

BACKGROUND: Chronic low back pain (CLBP) affects a large proportion of the population and has been associated with different muscle dysfunctions. However, there is no consensus regarding muscle electromyography and kinematic patterns during fatiguing tasks. OBJECTIVE: To examine whether trunk and limb muscle fatigability and activation patterns of individuals suffering CLBP differ from those of healthy participants during a holding task. DESIGN: Cross-sectional study. SETTING: Clinical research laboratory. PARTICIPANTS: Twenty-four participants with CLBP and 26 matched healthy controls. METHODS: Both groups performed a static holding task, in a semisquat position, until exhaustion. The performance variable was time to failure. Electromyography signs, such as median frequency and root mean square, were used to quantify fatigability by applying linear regression to each of the 3 successive test periods. Kinematic variables were monitored throughout the holding task. MAIN OUTCOME MEASUREMENTS: Independent t tests were used to compare time to failure. Electromyography-based measures of muscle fatigability were examined through a two-way, repeated-measures analysis of variance (mixed-model), whereas kinematic analysis was based on 2 multivariate analyses of variance. RESULTS: Although the groups differed in time to failure (healthy group: mean 201.6 seconds, SD 98.9 seconds; CLBP: mean 132.4 seconds, SD 78.9 seconds; P =.009), no statistically significant differences were found in electromyography-based measures of muscle fatigability, except for the internal oblique muscle. Kinematic variables were similar in the 2 groups. CONCLUSION: Despite similar electromyography fatigability in the 2 groups, individuals with CLBP seem to be more sensitive to certain effects of back muscle fatigue. Significant differences in electromyography measurements in the internal oblique muscle, both between groups and across periods, suggest that individuals with CLBP trigger a subtly different activation pattern to control the spine. In a holding task, compared with healthy people, this may represent a compensatory behavior aimed at adapting to certain deficits in spine control or pain. LEVEL OF EVIDENCE: II.

Differing Roles of Functional Movement Variability as Experience Increases in Gymnastics.

Current theories, like Ecological Dynamics, propose that inter-trial movement variability is functional when acquiring or refining movement coordination. Here, we examined how age-based experience levels of gymnasts constrained differences in emergent movement pattern variability during task performance. Specifically, we investigated different roles of movement pattern variability when gymnasts in different age groups performed longswings on a high bar, capturing the range of experience from beginner to advanced status. We also investigated the functionality of the relationships between levels of inter-trial variability and longswing amplitude during performance. One-hundred and thirteen male gymnasts in five age groups were observed performing longswings (with three different experience levels: beginners, intermediates and advanced performers). Performance was evaluated by analysis of key events in coordination of longswing focused on the arm-trunk and trunk-thigh segmental relations. Results revealed that 10 of 18 inter-trial variability measures changed significantly as a function of increasing task experience. Four of ten variability measures conformed to a U-shaped function with age implying exploratory strategies amongst beginners and functional adaptive variability amongst advanced performers. Inter-trial variability of arm-trunk coordination variables (6 of 10) conformed to a \-shaped curve, as values were reduced to complete the longswings. Changes in coordination variability from beginner to intermediate status were largely restrictive, with only one variability measure related to exploration. Data revealed how inter-trial movement variability in gymnastics, relative to performance outcomes, needs careful interpretation, implying different roles as task experience changes. Key pointsInter-trial variability while performing longswings on a high bar was assessed in a large sample (113 participants) divided into five age groups (form beginners to advanced gymnasts). Longswing assessment allowed us to evaluate inter-trial variability in representative performance context.Coordination variability presented two different configurations across experience levels depending on the variable of interest: either a U-shaped or a L- or \-shaped graph.Increased inter-trial variability of the functional phase events offered flexibility to adapt the longswing performance in the advanced gymnasts, while decreasing variability in arm-trunk coordination modes was critical to improve longswing and to achieve the most advanced level.In addition, the relationship between variability measures and the global performance outcome (i.e. the swing amplitude) revealed different functional roles of movement variability (exploratory or restrictive) as a function of changes in experience levels.

Reliability and validity of a custom-made instrument including a hand-held dynamometer for measuring trunk muscle strength.

BACKGROUND: Measuring isometric strength is necessary in many areas of health and sport. However, trunk muscles have some particular characteristics that make them difficult to evaluate with simple, inexpensive instruments. OBJECTIVE: To evaluate the reliability and validity of an instrument constructed with a hand-held dynamometer and a metallic structure (HHD+S) for measuring maximum isometric voluntary trunk muscle strength. METHODS: Maximum isometric voluntary trunk muscle strength (extension, flexion and lateral flexion) was measured in 20 healthy individuals using the custom-made instrument (HHD+S) and the gold standard Back-Check (BC). RESULTS: The results showed that the two instruments had high and similar intra-subject reliability. The validity of the HHD+S was demonstrated by the high Pearson coefficient correlation between the two instruments (r ⩾ 0.78). CONCLUSIONS: Given the good trial reliability and the close correlation between the two instruments, we believe that the use of a hand-held dynamometer together with the custom-made metallic structure (HHD+S) allows an evaluation of the maximum isometric voluntary trunk muscle strength to be made, that is very similar in quality, accuracy and reliability to the BC.