Abstract Objective To analyze the relation between contralesional and ipsilesional limbs in subjects with stroke during step-to-step transition of walking. Design Observational, transversal, ...analytical study with a convenience sample. Setting Physical medicine and rehabilitation clinic. Participants Subjects (n=16) with poststroke hemiparesis with the ability to walk independently and healthy controls (n=22). Interventions Not applicable. Main Outcome Measures Bilateral lower limbs electromyographic activity of the soleus (SOL), gastrocnemius medialis, tibialis anterior, biceps femoris, rectus femoris, and vastus medialis (VM) muscles and the ground reaction force were analyzed during double-support and terminal stance phases of gait. Results The propulsive impulse of the contralesional trailing limb was negatively correlated with the braking impulse of the leading limb during double support ( r =−.639, P =.01). A moderate functional relation was observed between thigh muscles ( r =−.529, P =.035), and a strong and moderate dysfunctional relation was found between the plantar flexors of the ipsilesional limb and the vastus medialis of the contralesional limb, respectively (SOL-VM, r =−.80, P <.001; gastrocnemius medialis-VM, r =−.655, P =.002). Also, a functional moderate negative correlation was found between the SOL and rectus femoris muscles of the ipsilesional limb during terminal stance and between the SOL ( r =−.506, P =.046) and VM ( r =−.518, P =.04) muscles of the contralesional limb during loading response, respectively. The trailing limb relative impulse contribution of the contralesional limb was lower than the ipsilesional limb of subjects with stroke ( P =.02) and lower than the relative impulse contribution of the healthy limb ( P =.008) during double support. Conclusions The findings obtained suggest that the lower performance of the contralesional limb in forward propulsion during gait is related not only to contralateral supraspinal damage but also to a dysfunctional influence of the ipsilesional limb.
Low back pain is one of the main causes of motor disabilities and psychological stress, with the painful process encompassing sensory and affective components. Noxious stimuli originate on the ...periphery; however, the stimuli are recombined in the brain and therefore processed differently due to the emotional environment. To better understand this process, our objective was to develop a mathematical representation of the International Association for the Study of Pain (IASP) model of pain, covering the multidimensional representation of this phenomenon. Data from the Oswestry disability index; the short form of the depression, anxiety, and stress scale; and pain catastrophizing daily questionnaires were collected through online completion, available from 8 June 2022, to 8 April 2023 (1021 cases). Using the information collected, an artificial neural network structure was trained (based on anomaly detection methods) to identify the patterns that emerge from the relationship between the variables. The developed model proved to be robust and able to show the patterns and the relationship between the variables, and it allowed for differentiating the groups with altered patterns in the context of low back pain. The distinct groups all behave according to the main finding that psychological and pain events are directly associated. We conclude that our proposal is effective as it is able to test and confirm the definition of the IASP for the study of pain. Here we show that the fiscal and mental dimensions of pain are directly associated, meaning that mental illness can be an enhancer of pain episodes and functionality.
The aim of the study is to characterize physical activity (PA) levels and PA readiness as well as stratify cardiovascular risk among the population of polytechnics community members in the north ...region of Portugal, including students, academic teachers, and non-teacher staff. An online questionnaire about general sample characterization, PA level, and readiness was applied. Of the 717 respondents, 237 were academic teachers, 143 were non-teacher staff, and 337 were students. Most of the participants had a level of moderate PA, including students, academic teachers, and non-teacher staff (82%). The sedentary behavior was higher in the academic teachers and non-teacher staff groups. A total of 56% of the participants had low cardiovascular risk; the group of students were the population with higher risk. Approximately half of the participants need to consult a qualified professional before increasing their PA. Overall, the participants presented moderate levels of PA, although there is still a considerable number of sedentary people that must be considered.
Abstract The study assessed the effect of velocity of arm movement on anticipatory postural adjustments (APAs) generation in the contralateral and ipsilateral muscles of individuals with stroke in ...seating. Ten healthy and eight post-stroke subjects were studied in sitting. The task consisted in reaching an object placed at scapular plane and mid-sternum height at self-selected and fast velocities. Electromyography was recorded from anterior deltoid (AD), upper (UT) and lower trapezius (LT) and latissimus dorsi (LD). While kinematic analysis was used to assess peak velocity and trunk displacement. Differences were found between the timing of APAs on ipsi and contralateral LD and LT in both movement speeds and in ipsilateral UT during movement of the non-affected arm at a self-selected velocity. A delay on the contralateral LD to reach movement with the non-affected arm at fast velocity was also observed. The trunk displacement was greater in post-stroke subjects. Individuals with stroke demonstrated a delay of APAs in the muscles on both sides of the body compared to healthy subjects. The delay was observed during performance of the reaching task with the fast and self-selected velocity.
Biomechanical gait parameters—ground reaction forces (GRFs) and plantar pressures—during load carriage of young adults were compared at a low gait cadence and a high gait cadence. Differences between ...load carriage and normal walking during both gait cadences were also assessed. A force plate and an in-shoe plantar pressure system were used to assess 60 adults while they were walking either normally (unloaded condition) or wearing a backpack (loaded condition) at low (70 steps per minute) and high gait cadences (120 steps per minute). GRF and plantar pressure peaks were scaled to body weight (or body weight plus backpack weight). With medium to high effect sizes we found greater anterior-posterior and vertical GRFs and greater plantar pressure peaks in the rearfoot, forefoot and hallux when the participants walked carrying a backpack at high gait cadences compared to walking at low gait cadences. Differences between loaded and unloaded conditions in both gait cadences were also observed.
•High ground reaction forces and plantar pressures are observed during load carriage at high gait cadences.•Special attention should be paid in the medial forefoot and medial rearfoot regions during load carriage at high gait cadences.•The pattern of force distribution is different between load carriage and normal walking during low and high gait cadences.•During load carriage changes on gait pattern appears to occur to protect the musculoskeletal system from high vertical forces.
Microcurrent therapy can increase lipolytic activity. However, it is unknown if the increased availability of lipids can influence the selection of energy substrates during a single session of ...aerobic exercise. We aimed to analyze the effect of microcurrent application to the abdominal region in the consumption of lipids and carbohydrates, and respiratory exchange ratio (RER) during a single session of moderate aerobic exercise in young adults. A pilot study was conducted in which participants were allocated to intervention (IG) or placebo (PG) groups. In both groups, 40 min of microcurrent application with two frequencies (25 and 10 Hz) followed by 50 min of moderate-intensity aerobic exercise (45−55% of heart rate reserve) on a cycloergometer were performed. The microcurrent application was performed without intensity in the PG. A portable gas analyzer (K4b2) was used during exercise in both groups. Thirty-eight participants (20.6 ± 1.8 years; 18 in IG and 20 in PG) were enrolled. There were no significant differences in the consumption of substrates or RER between the groups during exercise (p > 0.05). Microcurrent application seems to be insufficient to influence the consumption of energy substrates and RER during a single session of aerobic exercise in young adults.
This study aims to analyse the coactivation of antagonist muscles of the thigh and ankle during the sit-to-stand task in post-stroke subjects, specifically during forward and antigravity sub-phases. ...A group of 18 healthy subjects and another with 18 subjects with a history of stroke participated voluntarily in this study. Bilateral surface electromyography (EMGs) of the soleus, gastrocnemius medialis, tibialis anterior, rectus femoris and biceps femoris muscles were collected synchronously with ground reaction forces (GRF) during the sit-to-stand task. The magnitude of electromyographic (EMG) activity was analysed during forward translation and antigravity sub-phases which were determined through GRF signals. The coactivation was calculated to quantify the degree of antagonist coactivation according to the role of the muscles during the task. Statistically significant values were found between antagonist coactivation on both sub-phases of the sit-to-stand task when comparing healthy and post-stroke subjects (healthy with ipsilesional (IPSI); healthy with contralesional (CONTRA); and healthy with IPSI and with CONTRA limbs) in all muscle pairs analysed (p < 0.01), except on thigh muscles (p > 0.05), in the antigravity sub-phase. When comparing IPSI with CONTRA sides in post-stroke subjects, no statistically significant differences were found. Increased values of antagonist coactivation were observed in post-stroke subjects compared to healthy subjects (both IPSI and CONTRA limb) in the two sub-phases analysed. The forward sub-phase CONTRA limb showed higher antagonist coactivation compared to IPSI, while in the antigravity sub-phase, IPSI antagonist coactivation was higher than in the CONTRA. In conclusion, post-stroke subjects presented an antagonist coactivation more dysfunctional at the ankle joint muscles compared to the thigh segment. So, it seems that the distal segment could express more accurately the central nervous system dysfunction in post-stroke subjects, despite the need for further studies to achieve a better spatiotemporal understanding of the variability on coactivation levels.
Automation of assembly work was originally developed to increase operation efficiency and to reduce workload. However, a considerable number of unanticipated ergonomic problems have been observed ...such as the interaction between humans and automated systems. The aims of this study were to quantify joint angle positions (shoulder, elbow and wrist) of workers in two assembly lines with different mechanization levels and analyse the performance of an inertial motion capture system. Seven experienced female assemblers participated in this study. The measurements were performed in the workplace with a full-body inertial measurement system (Xsens MVN BIOMECH system). Maximum cross-correlation between angle-time courses was calculated to quantify the waveform similarities. In manual line, there are larger variations of joint angles than in the semi-automatic one. The analysis of cross correlation coefficients revealed that electromagnetic interferences are potential limitations to the use of these systems under field conditions.
This study aims to compare 2 methods of assessing the postural phase of gait initiation, in regard to intrasession reliability, in healthy and poststroke subjects. As a secondary aim, this study aims ...to analyze anticipatory postural adjustments during gait initiation based on the center of pressure (CoP) displacements in poststroke participants. The CoP signal was acquired during gait initiation in 15 poststroke subjects and 23 healthy controls. Postural phase was identified through a baseline-based method and a maximal displacement-based method. In both healthy and poststroke participants, higher intraclass correlation coefficient and lower coefficient of variation values were obtained with the baseline-based method when compared with the maximal displacement-based method. Poststroke participants presented decreased CoP displacement backward and toward the first swing limb compared with controls when the baseline-based method was used. With the maximal displacement based method, there were differences between groups only regarding backward CoP displacement. Postural phase duration in medial-lateral direction was also increased in poststroke participants when using the maximal displacement based method. The findings obtained indicate that the baseline-based method is more reliable detecting the onset of gait initiation in both groups, while the maximal displacement-based method presents greater sensitivity for poststroke participants.
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