Muscle Fatigue Research Articles

EMG Dataset for Gesture Recognition with Arm Translation

Myoelectric control has emerged as a promising approach for a wide range of applications, including controlling limb prosthetics, teleoperating robots and enabling immersive interactions in the Metaverse. However, the accuracy and robustness of myoelectric control systems are often affected by various factors, including muscle fatigue, perspiration, drifts in electrode positions and changes in arm position. The latter has received less attention despite its significant impact on signal quality and decoding accuracy. To address this gap, we present a novel dataset of surface electromyographic (EMG) signals captured from multiple arm positions. This dataset, comprising EMG and hand kinematics data from 8 participants performing 6 different hand gestures, provides a comprehensive resource for investigating position-invariant myoelectric control decoding algorithms. We envision this dataset to serve as a valuable resource for both training and benchmark arm position-invariant myoelectric control algorithms. Additionally, to expand the publicly available data capturing the variability of EMG signals across diverse arm positions, we propose a novel data acquisition protocol that can be utilized for future data collection.

Effect of Closed Kinetic Chain Exercise Via Telerehabilitation on Muscle Strength, Balance, Fatigue and Hemoglobin Levels in Beta Thalassemia Major Children: A Randomized Controlled Trial

Effect of Closed Kinetic Chain Exercise Via Telerehabilitation on Muscle Strength, Balance, Fatigue and Hemoglobin Levels in Beta Thalassemia Major Children: A Randomized Controlled Trial

The impact of fatigue on the jumping mechanics and injury risk of basketball players

Fatigue can significantly alter an athlete’s biomechanics and performance, which can increase their risk of injury. Important basketball moves like jump shots (JS) and countermovement jumps (CMJ) primarily use the muscles in the lower back and lower limbs. Basketball players’ jumping mechanics, performance, and risk of injury during CMJ, JS, and ankle sprains were all examined. A total of 415 male collegiate basketball players participated in the league, this season representing varying levels of jumping mechanics. Surface electromyography, a force plate, and a 3D motion analysis system were used to gather data. Field-goal percentage, the center of mass’s (CM) lowest point, joint angles during takeoff and landing, and Electromyography data from the lower leg muscles, erector spinae limbal, and rectus femoris were among the parameters that were recorded. Lower back muscle tiredness was created, and performance was evaluated after the fatigue. Data was analyzed using SPSS, with paired-sample t-tests, logistic, and Multiple Regression tests employed to examine the impact of fatigue on performance and injury risk. These tests assessed how fatigue affects shooting accuracy and joint angles, and increases the chance of injuries in basketball players. Following a period of tiredness, athletes’ field-goal percentages significantly decreased, whereas their CM lowest point increased on jump shots. In both CMJ and JS, fatigue leads to reduced knee flexion angles and increased ankle plantar flexion during landing, changing the contribution ratio of both legs. Due to impaired mechanics, these biomechanical changes suggest an increased probability of ankle sprains and an elevated risk of damage, especially during landing. The risk of lower back, knee, and ankle injuries increased due to major athletic impairments and altered landing mechanics caused by lower back muscular fatigue. To reduce basketball players’ risk of injury, these data highlight how crucial it is to address fatigue in training and recovery plans.

Effects of static stretching and walking during inter-set intervals of resistance training on muscle fatigue of the quadriceps

IntroductionInter-set rest intervals are essential to reduce muscle fatigue and increase the total amount of volume of resistance training. Static stretching and walking may increase muscle blood flow and promote recovery during inter-set rest intervals. Therefore, the purpose of this study was to investigate the effects of 20 seconds of static stretching and walking during inter-set rest intervals of leg extension exercises on the number of repetitions to exhaustion, total amount of volume, and flexibility of the quadriceps (joint range of motion and muscle hardness) in untrained healthy males.MethodsFourteen healthy, untrained men performed three different interventions (passive rest, static stretching, and walking) during inter-set rest intervals of a leg extension exercise with a 70% load of maximum muscle strength, in random order. The range of motion and muscle hardness of the quadriceps were measured before and immediately after all interventions using a goniometer and a portable muscle hardness meter. The number of repetitions to exhaustion and total amount of volume load (load × repetitions) of the leg extension exercise were assessed. Repeated two-way ANOVA and a Friedman test were used to analyze the variables.ResultsRange of motion and muscle hardness were increased after all interventions (both p < 0.05). There was no significant difference in the number of repetitions to exhaustion (p = 0.651) or total amount of volume load (p = 0.206) between interventions.DiscussionThese results indicated that static stretching and walking during inter-set rest intervals did not influence the change in flexibility and muscle fatigue of the leg extension exercise.

Intracellular Membrane Contact Sites in Skeletal Muscle Cells

Intracellular organelles are common to eukaryotic cells and provide physical support for the assembly of specialized compartments. In skeletal muscle fibers, the largest intracellular organelle is the sarcoplasmic reticulum, a specialized form of the endoplasmic reticulum primarily devoted to Ca2+ storage and release for muscle contraction. Occupying about 10% of the total cell volume, the sarcoplasmic reticulum forms multiple membrane contact sites, some of which are unique to skeletal muscle. These contact sites primarily involve the plasma membrane; among these, specialized membrane contact sites between the transverse tubules and the terminal cisternae of the sarcoplasmic reticulum form triads. Triads are skeletal muscle-specific contact sites where Ca2+ channels and regulatory proteins assemble to form the so-called calcium release complex. Additionally, the sarcoplasmic reticulum contacts mitochondria to enable a more precise regulation of Ca2+ homeostasis and energy metabolism. The sarcoplasmic reticulum and the plasma membrane also undergo dynamic remodeling to allow Ca2+ entry from the extracellular space and replenish the stores. This process involves the formation of dynamic membrane contact sites called Ca2+ Entry Units. This review explores the key processes in biogenesis and assembly of intracellular membrane contact sites as well as the membrane remodeling that occurs in response to muscle fatigue.

Kinesio Taping does not Enhance Jump Performance and Muscle Activity in Female Athletes.

This study aimed to investigate the effect of Kinesio Taping (KT) application on the single-leg counter-movement jump (CMJ) and surface electromyographic (sEMG) activity in trained female athletes, in both resting and fatigued states. In this single-blind, randomized, sham-controlled trial, twenty-four healthy trained female athletes were randomly assigned to either the KT (n=12) or the sham tape group (n=12). KT was applied using an inhibition technique on rectus femoris, vastus medialis, biceps femoris, and lateral gastrocnemius muscles of the dominant leg. A single-leg CMJ test and sEMG activity were recorded at baseline (no tape), as well as at 1 hour, 24 hours, and 48 hours after taping. To induce acute neuromuscular fatigue, a 30-second repetitive CMJ test was used to evaluate KT in fatigued states. In the resting states, both groups exhibited improvements in jump height, power, mean velocity, and sEMG activity (%EMGmax) over time, with no significant between-group differences. The single-leg CMJ performance was similarly decreased after the muscle fatigue protocol in both groups, showing no between-group differences. Our findings suggest that KT treatment does not appear to influence jumping performance, sEMG activity, or muscle fatigue in female athletes.

Impact of muscle fatigue on anticipatory postural adjustments during gait initiation

IntroductionProlonged or strenuous exercise leads to a temporary decrease in muscle function and performance, which interferes with activity of both prime movers and postural muscles. This effect of fatigue has been reported both for single segment movements and for locomotion. However, little is known regarding the effects of fatigue on anticipatory postural adjustments (APAs) during gait initiation, a task in which the control of focal movement should be strictly coupled to a feedforward control of posture.MethodsWe studied APAs during gait initiation in 16 healthy well-trained adult males, searching for muscle activities that precede the backward shift of the Center of Pressure (CoP). Participants stood on a force plate for about 10 s and then started walking at their natural speed. APAs were evaluated before and after a 1 min exhausting sequence of countermovement jumps. An optoelectronic system captured the heel-off events while a force plate measured the CoP position and vertical ground reaction force. Wireless probes recorded the electromyogram of trunk and leg muscles from both sides.ResultsIt was observed that muscle fatigue delayed excitatory and inhibitory APAs, of about 40 and 80 ms, respectively, and a parallel delay was induced on prime movers; moreover, velocity and amplitude of backward CoP shift were reduced. Regarding APAs sign and occurrence, most of the participants showed bilateral inhibition in dorsal muscles and excitation in the ventral ones, displaying a forward “diving” strategy that was almost unaffected by fatigue. However, after fatigue, three of the “diving” participants switched to a “turning” strategy, i.e., they displayed a reciprocal activation/inhibition pattern in the dorsal muscles, compatible with a trunk rotation.DiscussionThe “turning” strategy has been previously described in untrained individuals and in a toes-amputee mountain climber, who showed a “diving” approach to gait initiation when wearing his prosthetic shoes and switched to the “turning” approach when barefoot. Altogether, these results support the idea that one and the same person may develop a repertoire of postural strategies among which the central nervous system will choose, according to the personal fitness and the constraints in which the action is performed.

Observational study: effect of varying transport durations and feed withdrawal on the physiological status and health of dairy calves

Long-distance transport and associated fasting of unweaned calves have the potential to compromise the animals’ welfare. This observational study aimed to determine how transport and fasting durations impacted the physiology and health of 115 transported calves in three transport groups; IRE (n = 20, mean age 29.8d; short road transport (~ 29 h incl. resting time) and short feed deprivation (~ 11 h)), INT (n = 65, mean age 24.9d; long road/ferry transport (~ 79 h incl. resting times) and long feed deprivation (~ 28 h and 25 h)), and NLD (n = 30, mean age 17.7d; short road transport (~ 28 h incl. resting time) and long feed deprivation (> 18 h)). All calves travelled through an assembly centre. Each calf was blood sampled (arrival at destination farm, 1-week and 3-weeks post-arrival), health scored (arrival, 1, 3, 7, 8, 20d post-arrival) and weighed (farm/mart of origin [IRE and INT only], arrival, and 3-weeks post-arrival). (Generalised) linear mixed models were used to analyse differences in blood variables, weight, and health scores on arrival and during recovery (all other timepoints). Despite differing transport durations, both INT and NLD calves exhibited glucose, beta-hydroxy-butyrate, non-esterified-fatty-acids and sodium levels outside reference limits upon arrival, which were different from values observed in IRE calves (p < 0.05). Lactate and potassium were above reference range for INT calves on arrival, and higher than in IRE and NLD groups (p < 0.05). One- and three-weeks post arrival, most variables returned to within reference ranges, and differences between groups were minimal and not clearly associated with either transport duration or fasting during transport. Health scores did not differ between transport groups at arrival, and differences were minimal during the three-week recovery period. INT calves lost more weight during the journey than IRE calves (p < 0.01), while INT and NLD calves gained similar weight in the 3-weeks post-arrival, but less than IRE calves (both p < 0.01). Overall, changes in the physiological status of calves post transport appeared to relate more to the duration of feed deprivation than to the duration of transport, except for potassium and lactate (muscle fatigue), which were impacted more for INT calves. Most variables showed clear signs of recovery to within reference levels for all groups within three weeks. Minimizing the duration of feed deprivation during transport should be a key consideration for the dairy industry to reduce the impact of transport on calf welfare.

Hamstring Strain in Sprinting Athletes: Biomechanics, Risk Factors, and Injury Prevention Strategies

Hamstringrelated injuries, primarily hamstring strain, frequently affect both recreational and professional athletes, especially in sports that involve running, jumping, kicking, and sudden directional changes. This study presents a comprehensive analysis of HSIs, covering anatomical and biomechanical factors, kinematics, diagnostic methods, and strategies for prevention and treatment. Although the exact mechanism of HSIs during sprinting remains uncertain, no specific phase of the running cycle has been identified as presenting the highest risk. Stretch-induced HSIs, often triggered by excessive hip flexion and knee hyperextension, place significant stress on the proximal tendon and musculotendinous junction, particularly affecting the semimembranosus muscle. Risk factors for HSIs are categorized as non-modifiable (age, previous injuries, playing position) and modifiable (muscle weakness, fatigue, imbalances, limited flexibility, and poor neuromuscular control). Physiotherapy approaches that emphasize eccentric strength trainingprogressing through flexibility, stabilization, and specific strength phasesreduce injury rates, especially when integrated with concentric training in sprinting related sports

Effects of photobiomodulation therapy on acute recovery after exhausting cycling exercise

The application of photobiomodulation therapy (PBMT) to delay skeletal muscle fatigue and shield against muscle damage represents a novel frontier in the field of exercise physiology. Further research is warranted to understand the physiological impact of PBMT on post-exercise recovery and muscle functionality. The objective of this research is to assess the impact of PBMT on the quadriceps following strenuous cycling, focusing on blood lactate (BL) levels, heart rate (HR), perceived exertion (RPE), and performance in the Wingate (WG) test. The study involved 12 male participants who were randomly allocated to either an active PBMT group or a control group, with treatments administered to the rectus femoris muscles bilaterally post-exhaustive cycling. The cycling exercise workload was 50 Watts (W); it increased by 50 W every 30 s at 60 rpm until the onset of exhaustion; and 30 s of active recovery was allowed between intervals. The BL, HR, and RPE were measured at several time points: pre-exercise, post-exercise, and at 10 min and 20 min post-exercise, as well as post-WG test. BL was significantly reduced in the PBMT group compared to the placebo group at the 10-min (p &lt; 0.05) and 20-min (p &lt; 0.01) marks post-exercise, and also post-WG test (p &lt; 0.01). Additionally, HR was significantly lower in the PBMT group immediately following the WG test (p &lt; 0.01). Both the mean (p &lt; 0.05) and peak power outputs (p &lt; 0.05) were found to be superior in the PBMT group. The application of PBMT to the quadriceps post-exhaustive exercise resulted in reduced BL and HR, along with improved WG test results, suggesting that PBMT may facilitate faster recovery following physical exertion.

Effect of induced extrinsic and intrinsic hand and forearm muscular fatigue on the control of finger force during piano playing.

This study aimed to investigate the effect of hand muscle fatigue on finger control and force efficiency during piano performance, which is crucial for skilled piano playing among professional pianists engaged in prolonged periods of high-intensity practice or concert preparation. Thirty-one professional pianists were recruited as participants. This study was divided into three sequential experimental parts: pre-fatigue test, fatigue protocol, and post-fatigue test. Each participant was assigned eight piano skills and instructed to perform two fatigue tasks: finger extension and finger grasping exercises. The study recorded and analyzed the finger force of professional pianists using a sensor-embedded kinetic assessment piano system; wrist movements were assessed using a three-dimensional motion capture system. Paired t-tests were used to determine the differences between the pre- and post-tests. The findings showed that the average peak striking force of most fingers in Chords 1, 2, 4, 5, 6, and 7 decreased significantly after the fatigue task, indicating a reduction in the finger-striking force following fatigue across the various chord fingerings. The analysis of wrist movements demonstrated strategic adjustments made by pianists after experiencing fatigue, particularly in the ulnar/radial deviation movements. This study highlights the influence of muscle fatigue on finger control and wrist movements of pianists across different fingerings. We recommend that pianists focus on strengthening the extrinsic and intrinsic muscles of the hand and the muscle groups responsible for controlling ulnar/radial movements to mitigate the effects of muscular fatigue on hand performance.

Effectiveness of Using a Digital Wearable Plantar Pressure Device to Detect Muscle Fatigue: Within-Subject, Repeated Measures Experimental Design.

Muscle fatigue, characterized by reduced force generation during repetitive contractions, impacts older adults doing daily activities and athletes during sports activities. While various sensors detect muscle fatigue via muscle activity, biochemical markers, and kinematic parameters, a real-time wearable solution with high usability remains limited. Plantar pressure monitoring detects muscle fatigue through foot loading changes, seamlessly integrating into footwear to improve the usability and compliance for home-based monitoring. This study aimed to investigate the effects of muscle fatigue on plantar pressure measurements using a self-developed wearable plantar pressure system. Twelve healthy participants completed a 5-minute calf muscle fatigue protocol. The plantar pressures and surface electromyography (sEMG) activity of the gastrocnemius muscles were recorded before and after exercise. The plantar pressures at 6 regions and the median frequency (MDF) of sEMG were analyzed to quantify fatigue. The self-developed foot pressure system showed a significant decrease in plantar pressure peak values at the heel of the left (P=.003) and right feet (P=.001) and at the lateral toe of the left (P=.001) and right feet (P=.026). A significant increase was observed at the metatarsal head of both the left foot (P=.001) and the right foot (P=.017). The MDF of sEMG signals significantly decreased in the left (P=.001) and right gastrocnemius (P<.001). Plantar pressure changes and sEMG signals effectively detect gastrocnemius muscle fatigue using the proposed wearable system, supporting the development of a wearable solution for detecting muscle fatigue suitable for home-use.

CLINICAL JUSTIFICATION OF THE EFFICIENCY OF USING IMPROVED METHODS OF DETERMINING AND FIXING OCCLUSAL RELATIONSHIPS IN PATIENTS WITH PARTIAL EDENTULOUS

Determining the optimal occlusal relationships according to the anatomical and functional features of the maxillofacial system (MFS) and subsequent adaptation till physiological functions are restored is an actual task during prosthetic treatment of patient with partial edentulous with help of fixed and removable partial denture (FPD, RPD). Purpose: to establish the effectiveness of the proposed methods of determining and fixing of the occlusal relationships based on the study of clinical indicators in patients who simultaneously use FPD and RPD for prosthetic therapy. Material and Methods. Our study included 120 patients aged 55-70 years with partial edentulous without endocrine and systemic disorders, acute forms of periodontal tissues diseases and good level of individual oral hygiene who came to the Department of Stomatology of Postgraduate Education of Ivano-Frankivsk National Medical University for prosthetic treatment. Prosthetic treatment was carried out with FPD, RPD using the proposed methods of forming occlusal relationships (group 1) and generally accepted methods (group 2). Each study group was divided into two subgroups: a – patients without occlusal disorders, and b – patients with occlusal disorders and vertical occlusion dimension (VOD) loss. The examination of each person included the collection of anamnesis and complaints, general dental examination, the determination of the Russell periodontal index (PI), the assessment of occlusal relationships and the condition of the temporomandibular joint (TMJ) according to "Hamburg protocol". Results and conclusions. The analysis of patient’s complaints and anamnesis, the data of the objective dental examination, and assessment of the periodontal tissue condition established the effectiveness of the proposed methods of determining and fixing occlusal relationships in patients with partial edentulous simultaneously treated with FPD and RPD. In addition, 23.3% more people of the 2a subgroup felt tension and fatigue of the masticatory muscles a week after treatment than in 1a subgroup, and 36.7% more - in the 2b subgroup than in 1b after a year of FPD and RPD use (p&lt; 0,05). There were significantly more patients with signs of eccentric supraocclusion in the 2a subgroup a year after prosthetic treatment than in 1a (30±0.09% (9) and 3.3±0.03% (1)), and with signs of centric supraocclusion in the 2b subgroup - 36.7±0.09% (11), against 10±0.06% (6) in 1b (p &lt;0.05). Also, there was observed a positive effect of proposed method of determining and fixing of the occlusal relationships during prosthetic treatment on TMJ a year after prosthetic treatment with FPD and RPD. There were 16.7% and 13.3% fewer people in 1a and 1b subgroups with one positive symptom of the “Hamburg protocol” and 6.7% and 40% fewer persons with two positive symptoms, compared to the data received before treatment. There was an increase by 13.3% of number of patients with one positive symptom according to “Hamburg protocol” in the 2a subgroup and by 10% of persons with two symptoms. It was determined a decrease of patients with two positive symptoms according to “Hamburg protocol” in 2b subgroup by 10% after one year. An improvement of periodontal tissues condition of abutment teeth was evaluated by PI assessment after a year of observation of patients. It was established that the average value of PI in subgroup 1b was significantly lower by 57.6% than in subgroup 2b, and it was lower in subgroup 1a by 39.3% than in patients of subgroup 2a (р&lt;0,05).

Stimulation-Induced Muscle Deformation Measured With A-Mode Ultrasound Correlates With Muscle Fatigue

Stimulation-Induced Muscle Deformation Measured With A-Mode Ultrasound Correlates With Muscle Fatigue

Thoracic load carriage impairs the acute physiological response to hypoxia in healthy males.

To assess the impact of thoracic load carriage on the physiological response to exercise in hypoxia. Healthy males (n = 12) completed 3 trials consisting of 45 min walking in the following conditions: (1) unloaded normoxia (UN; FIO2:20.93%); (2) unloaded hypoxia (UH; FIO2:~13.0%); and (3) loaded hypoxia (LH; 29.5 kg; FIO2:~13.0%). Intensity was matched for absolute VO2 (2.0 ± 0.2 L·min-1) across conditions and relative VO2 (64.0 ± 2.6 %VO2max) across hypoxic conditions. With LH versus UH, there were increases in breathing frequency (5-11 breaths·min-1; p < 0.05) and decreases in tidal volume (10%-18%; p < 0.05) throughout exercise due to reductions in end inspiratory lung volumes (p < 0.05). Consequently, deadspace (11%-23%; p < 0.05) and minute ventilation (7%-11%; p < 0.05) were increased starting at 20 and 30 min, respectively. In addition, LH increased perceived exertion/dyspnea and induced inspiratory (~12%; p < 0.05 vs. UN) and expiratory (~10%; p < 0.05 vs. pre-exercise) respiratory muscle fatigue. Expiratory flow limitation was present in 50% of subjects during LH. Cardiac output and muscle oxygenation were maintained during LH despite reduced stroke volume (6%-8%; p < 0.05). Finally, cerebral oxygenated/total hemoglobin were elevated in the LH condition versus UH starting at 15 min (p < 0.05). Thoracic load carriage increases physiological strain and interferes with the compensatory response to hypoxic exposure.

Maximal inspiratory pressure and exercise-induced inspiratory muscle fatigue in chronic nonspecific low back pain

Patients with chronic nonspecific low back pain (CNSLBP) show reduced inspiratory muscle function. However, studies comparing maximal inspiratory pressure (MIP) and exercise-induced inspiratory muscle fatigue (IMF) between CNSLBPand healthy controls (HC) are lacking. To compare MIP and exercise-induced IMF between CNSLBPand HC. Cross-sectional study. MIP was recorded in 25 persons with CNSLBP and 15 HC before and immediately, 15 and 30 minutes after a maximal cardiopulmonary exercise test. Inspiratory muscle weakness was defined as a predicted MIP value lower than 80%, and exercise-induced IMF as a ≥10% reduction in MIP following the exercise test. Baseline MIP was similar between CNSLBP (109±32 cmH2O) and HC (116±32 cmH2O) (p= 0.525). Inspiratory muscle weakness was present in 36% of the CNSLBP group and in 20% of the HC group, with no significant difference between groups (p= 0.777). None of the groups showed significant exercise-induced IMF immediately (CNSLBP: -2.1%, HC: 3.7%), 15 minutes (CNSLBP: -5.4%, HC: -5.2%), and 30 minutes (CNSLBP: -4.7%, HC: -6.6%) after the maximal exercise test (p> 0.05), with no between group differences with regard to magnitude and proportion (CNSLBP: 24%, HC: 33%) (p> 0.05). This study shows that there is no difference in MIP and the proportion of inspiratory muscle weakness between persons with CNSLBP and HC. Additionally, within both groups, there was no exercise-induced IMF immediately, 15 and 30 minutes after a maximal exercise test. Furthermore, there was no difference in the magnitude and proportion of exercise-induced IMF between both groups.

Sleep Bruxism in Children: A Narrative Review.

Sleep bruxism, characterized by involuntary grinding or clenching of the teeth and/or by bracing or thrusting of the mandible during sleep, is common in children. Sleep bruxism occurs while the patient is asleep. As such, diagnosis can be difficult as the affected child is usually unaware of the tooth grinding sounds. This article aims to familiarize physicians with the diagnosis and management of sleep bruxism in children. A search was conducted in May 2023 in PubMed Clinical Queries using the key terms "Bruxism" OR "Teeth grinding" AND "sleep". The search strategy included all observational studies, clinical trials, and reviews published within the past 10 years. Only papers published in the English literature were included in this review. According to the International classification of sleep disorders, the minimum criteria for the diagnosis of sleep bruxism are (1) the presence of frequent or regular (at least three nights per week for at least three months) tooth grinding sounds during sleep and (2) at least one or more of the following (a) abnormal tooth wear; (b) transient morning jaw muscle fatigue or pain; (c) temporary headache; or (d) jaw locking on awaking. According to the International Consensus on the assessment of bruxism, "possible" sleep bruxism can be diagnosed based on self-report or report from family members of tooth-grinding sounds during sleep; "probable" sleep bruxism based on self-report or report from family members of tooth-grinding sounds during sleep plus clinical findings suggestive of bruxism (e.g., abnormal tooth wear, hypertrophy and/or tenderness of masseter muscles, or tongue/lip indentation); and "definite" sleep bruxism based on the history and clinical findings and confirmation by polysomnography, preferably combined with video and audio recording. Although polysomnography is the gold standard for the diagnosis of sleep bruxism, because of the high cost, lengthy time involvement, and the need for high levels of technical competence, polysomnography is not available for use in most clinical settings. On the other hand, since sleep bruxism occurs while the patient is asleep, diagnosis can be difficult as the affected child is usually unaware of the tooth grinding sounds. In clinical practice, the diagnosis of sleep bruxism is often based on the history (e.g., reports of grinding noises during sleep) and clinical findings (e.g., tooth wear, hypertrophy and/or tenderness of masseter muscles). In childhood, sleep-bruxism is typically self-limited and does not require specific treatment. Causative or triggering factors should be eliminated if possible. The importance of sleep hygiene cannot be over-emphasized. Bedtime should be relaxed and enjoyable. Mental stimulation and physical activity should be limited before going to bed. For adults with frequent and severe sleep bruxism who do not respond to the above measures, oral devices can be considered to protect teeth from further damage during bruxism episodes. As the orofacial structures are still developing in the pediatric age group, the benefits and risks of using oral devices should be taken into consideration. Pharmacotherapy is not a favorable option and is rarely used in children. Current evidence on the effective interventions for the management of sleep bruxism in children is inconclusive. There is insufficient evidence to make recommendations for specific treatment at this time.

Impact of Ergonomics on Undergraduate Physiotherapy Students in Bangladesh

Background: Poor ergonomics is a global concern, contributing to musculoskeletal complaints mostly muscle imbalance, strain, and fatigue among university students due to abnormal posture. Purpose: The purpose of the study was to identify the impact of ergonomics on undergraduate physiotherapy students in Bangladesh. Methodology: The cross-sectional study was carried out from November 2021 to July of 2022. The convenience sampling technique was used to collect data from 210 undergrad physiotherapy students studying at different physiotherapy colleges or institute in Bangladesh. The modified ergonomics related self-questionnaire was used to explore the idea, knowledge and awareness about the correct posture, and the Numeric Pain Rating Scale (NPRS) was used to collect data about the severity of musculoskeletal pain. Data was collected through face-to-face interviews, and the Statistical Package for Social Sciences (SPSS) version 26.0 was used for analysis. Results: The mean age ± SD of the students was 23.13 ± 2.484. Out of 210 respondents, the majority of the respondents (54.8%) were males, and most of them from crowed area (50.5%). The most of the student’s was Muslim (89.0%) while maximum were single (80.5%). The most of the students have to attend on the class in sitting posture up to 6-8 hours (69.5%) daily. The students have lack of postural awareness and forward bending is their preferred posture. The maximum participants (57.90%) had lower back pain, while 25.8% of had been prevented from doing their normal work due to pain. The results of the study showed a strong association between the study hours daily and correct sitting posture of the students (χ2 = 11.008, df = 5, and p = 0.004). Conclusion: The study found that professional physiotherapy students have low ergonomics awareness and the benefits of its proper use. The preventive training and physiotherapy programs could effectively reduce musculoskeletal complaints among the undergraduate students.

Evaluation of an assistive exosuit for alleviating neck and shoulder muscle fatigue during prolonged flexed neck posture

Evaluation of an assistive exosuit for alleviating neck and shoulder muscle fatigue during prolonged flexed neck posture

What are the potential mechanisms of fatigue-induced skeletal muscle hypertrophy with low-load resistance exercise training?

High-load resistance exercise (>60% of 1-repetition maximum) is a well-known stimulus to enhance skeletal muscle hypertrophy with chronic training. However, studies have intriguingly shown that low-load resistance exercise training (RET) (≤60% of 1-repetition maximum) can lead to similar increases in skeletal muscle hypertrophy as compared to high-load RET. This has raised questions about the underlying mechanisms for eliciting the hypertrophic response with low-load RET. A key characteristic of low-load RET is performing resistance exercise to, or close to, task failure, thereby inducing muscle fatigue. The primary aim of this evidence-based narrative review is to explore whether muscle fatigue may act as an indirect or direct mechanism contributing to skeletal muscle hypertrophy during low-load RET. It has been proposed that muscle fatigue could indirectly stimulate muscle hypertrophy through increased muscle fibre recruitment, mechanical tension, ultrastructural muscle damage, the secretion of anabolic hormones, and/or alterations in the expression of specific proteins involved in muscle mass regulation (e.g., myostatin). Alternatively, it has been proposed that fatigue could directly stimulate muscle hypertrophy through the accumulation of metabolic by-products (e.g., lactate), and/or inflammation and oxidative stress. This review summarizes the existing literature eluding to the role of muscle fatigue as a stimulus for low-load RET-induced muscle hypertrophy and provides suggested avenues for future research to elucidate how muscle fatigue could mediate skeletal muscle hypertrophy.