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PloS One 2024Muscle fatigue is one of the leading causes that contributes tremendously to injuries among volunteer firefighters in the workplace. The purpose of this study was to...
Muscle fatigue is one of the leading causes that contributes tremendously to injuries among volunteer firefighters in the workplace. The purpose of this study was to investigate the impact of positive-pressure breathing apparatus on muscle fatigue in the shoulder, back, and legs of volunteer firefighters. A total of 60 volunteer firefighters were recruited to perform a running task on a motorized treadmill in a controlled laboratory environment. Surface electromyography and rating of perceived exertion scores were collected from all participants every 60 seconds during the running task. Results show that the median frequency values for all measured muscle groups were significantly lower, and the rating of perceived exertion score was significantly higher after running with the positive-pressure breathing apparatus. Meanwhile, there were no significant differences in the median frequency values for the upper trapezius, erector spinae, and biceps femoris between the initial and final periods of running task without load. However, the median frequency values with load for gastrocnemius, rectus femoris, and tibialis anterior exhibited a greater downward trend compared to those without load. Additionally, using a breathing apparatus can cause asymmetric muscle fatigue in bilateral upper trapezius, erector spinae, gastrocnemius, and tibialis anterior muscles. The decreased performance due to muscle fatigue increases the risk of accidents, thereby posing a threat to the safety of volunteer firefighters. This study offers valuable insights into the effects of positive-pressure breathing apparatus on muscle fatigue among volunteer firefighters. These results may serve as a reference for developing improved fatigue management strategies and optimizing the design features of breathing apparatus.
Topics: Humans; Muscle Fatigue; Firefighters; Adult; Male; Electromyography; Muscle, Skeletal; Volunteers; Female; Running
PubMed: 38913654
DOI: 10.1371/journal.pone.0305599 -
Frontiers in Nutrition 2024Physical exertion during exercise often leads to increased oxidative stress and inflammatory responses, significantly affecting physical performance. Current strategies...
BACKGROUND
Physical exertion during exercise often leads to increased oxidative stress and inflammatory responses, significantly affecting physical performance. Current strategies to mitigate these effects are limited by their effectiveness and potential side effects. Molecular hydrogen (H₂) has gained attention for its antioxidant and anti-inflammatory properties. Studies have suggested that H supplementation contributes to antioxidant potential and anti-fatigue during exercise, but the variance in the observations and study protocols is presented across those studies.
OBJECTIVE
This systematic review and meta-analysis aimed to comprehensively characterize the effects of H₂ supplementation on physical performance (i.e., endurance, muscular strength, and explosive power), providing knowledge that can inform strategies using H for enhancing physical performance.
METHODS
We conducted a literature search of six databases (PubMed, Web of Science, Medline, Sport-Discus, Embase, and PsycINFO) according to the PRISMA guidelines. The data were extracted from the included studies and converted into the standardized mean difference (SMD). After that, we performed random-effects meta-analyses and used the statistic to evaluate heterogeneity. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to assess the quality of the evidence obtained from this meta-analysis.
RESULTS
In total, 27 publications consisting of 597 participants were included. The search finally included aerobic endurance, anaerobic endurance, muscular strength, lower limb explosive power, rating of perceived exertion (RPE), blood lactate (BLA), and average heart rate (HR) in the effect size (ES) synthesis. The ES of H on aerobic endurance, including V̇O (SMD = 0.09, = 0.394; = 0%) and aerobic endurance exercise (SMD = 0.04, = 0.687; = 0%), were not significant and trivial; the ES of H on 30 s maximal anaerobic endurance (SMD = 0.19, = 0.239; = 0%) was not significant and trivial; the ES of H on muscular strength (SMD = 0.19, = 0.265; = 0%) was not significant and trivial; but the ES of H on lower limb explosive power (SMD = 0.30, = 0.018; = 0%) was significant and small. In addition, H reduces RPE (SMD = -0.37, = 0.009; = 58.0%) and BLA (SMD = -0.37, = 0.001; = 22.0%) during exercise, but not HR (SMD = -0.27, = 0.094; = 0%).
CONCLUSION
These findings suggest that H supplementation is favorable in healthy adults to improve lower limb explosive power, alleviate fatigue, and boost BLA clearance, but may not be effectively improving aerobic and anaerobic endurance and muscular strength. Future studies with more rigorous designs are thus needed to examine and confirm the effects of H on these important functionalities in humans.
SYSTEMATIC REVIEW REGISTRATION
http://www.crd.york.ac.uk/PROSPERO.
PubMed: 38903627
DOI: 10.3389/fnut.2024.1387657 -
Frontiers in Sports and Active Living 2024Professional athletes navigate a multitude of unique challenges associated to sport-specific factors (e.g., training, travel and competition) and non-sport factors...
BACKGROUND
Professional athletes navigate a multitude of unique challenges associated to sport-specific factors (e.g., training, travel and competition) and non-sport factors (e.g., performance pressure, stress and anxiety) that can interfere with healthy sleep behaviors. Sleep plays a key role in proper biopsychosocial development as well as short- and long-term biological, physical, psychological, and cognitive health. As poor sleep quality is known to impair proper brain function, this study aimed to investigate the effect of sleep quality on a professional athlete's ability to train, recover, and perform, as well as their overall emotional and physical well-being.
METHODS
A cohort study was performed in 40 professional male cricket athletes from the Dutch national cricket team (mean age 26.5 ± 5.1 years). The athletes were monitored across a 22 weeks in-season training period. Sleep quality and overall emotional and physical well-being were assessed using daily sleep diaries and questionnaires which scored the readiness to train, stress levels, fatigue, muscle soreness and flu symptoms respectively. Quality of sleep and subsequent association with the consecutive elements of the well-being questionnaire were assessed through statistical using the student -test and clinical differences with the methodology of Osoba and colleagues: <5% "no change", 5%-10% "little change"; 10%-20% "moderate change"; and >20% "very much change".
RESULTS
The results demonstrated that the professional athletes assessed their sleep quality as average with a mean score of 3.4 out of 5. Lower perceived quality of sleep (<75th percentile) was correlated with a decreased readiness to train (mean score 3.2 [IQR: 3.0-4.0] vs. 3.5 [IQR: 3.0-5.0]; < 0.001) and increased extent of muscle soreness (2.7 [IQR: 2.0-3.0] vs. 2.3 [IQR: 2-3]; < 0.001), stress level (mean score 2.3 [IQR: 2.0-3.0] vs. 1.9 [IQR: 1.0-2.0]; < 0.001) and perceived fatigue (mean score 2.9 [IQR: 2.0-3.0] vs. 2.3 [IQR: 2.0-3.0]; < 0.001). Likewise, in patients with lower perceived quality of sleep, the proportion of players presenting with flu symptoms increased over 4-fold (4.1% vs. 17%; < 0.001).
CONCLUSIONS
This study highlights that good sleep quality positively influences the overall emotional and physical well-being of professional athletes. Our results emphasize the importance of targeted sleep interventions to improve sleep quality and subsequently optimize psychological and physiological wellness.
PubMed: 38903388
DOI: 10.3389/fspor.2024.1389565 -
BMC Sports Science, Medicine &... Jun 2024Respiratory muscle training plays a significant role in reducing blood lactate concentration (bLa) and attenuating negative physiological stress reactions. Therefore, we...
Respiratory muscle training plays a significant role in reducing blood lactate concentration (bLa) and attenuating negative physiological stress reactions. Therefore, we investigated if voluntary isocapnic hyperpnoea (VIH) performed after a maximum anaerobic effort influences bLa and perceived fatigue level in well-trained speedskaters. 39 elite short-track speedskaters participated in a trial with two parallel groups: experimental and control. All the participants performed the Wingate Anaerobic Test (WAnT). The experimental group performed a VIH-based recovery protocol 20 min after exercise, the control group used passive recovery only. Blood samples were taken 3 and 30 min after the WAnT to measure bLa. Fatigue was self-appraised on a 0-10 perceived rating-of-fatigue (ROF) scale 3 and 30 min after the WAnT. Noteworthy, but not statistically significant changes between the experimental and control groups were observed for changes in bLa (p = 0.101). However, statistically significant changes between the groups were found for ROF (p = 0.003, η = 0.211, ω = 0.106). Moreover, statistically significant interactions between post-exercise bLa clearance and VOmax (p = 0.028) and inspiratory muscle strength (p = 0.040) were observed. Our findings provided preliminary insight that VIH may be an efficient recovery protocol after anaerobic exercise performed by elite athletes. The association between VOmax and post-exercise bLa clearance indicates the vital role of aerobic fitness in repeated-efforts ability in short-track speedskaters. The study was registered at ClinicalTrials.gov as NCT05994092 on 15th August 2023.
PubMed: 38902811
DOI: 10.1186/s13102-024-00927-0 -
BMC Neurology Jun 2024We analyzed the changes in various motor function scores over a four-year period in patients with non-ambulatory spinal muscular atrophy (SMA) during Nusinersen...
We analyzed the changes in various motor function scores over a four-year period in patients with non-ambulatory spinal muscular atrophy (SMA) during Nusinersen treatment. Patients underwent Hammersmith Infant Neurological Examination (HINE) or Hammersmith Functional Motor Scale Expanded (HFMSE) before treatment, and approximately every 4 months thereafter. Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) or Children's Hospital of Philadelphia - Adult Test of Neuromuscular Disorders (CHOP ATEND), Revised Upper Limb Module (RULM), and Motor Function Measure (MFM) were performed based on baseline functional status. Narrative interviews were conducted to explore post-treatment physical improvement regarding activities of daily living (ADLs) and fatigue after ADLs. Based on HFMSE results, 9 patients achieved minimum clinically important differences. Average rates of change (slopes) with corresponding 95% confidence intervals for all assessment tools were in a positive direction. CHOP-INTEND showed the most prominent improvement in children and adolescents followed by HFMSE. Improvements in CHOP-ATEND were most noticeable in adults. Improvements were accompanied by changes in ADLs as observed in the narrative interviews. It is necessary to consider various functional aspects to determine the effectiveness of Nusinersen therapy. The objective assessment of the therapeutic effect of Nusinersen in non-ambulatory SMA requires consideration of functional aspects and the related ADLs.
Topics: Humans; Male; Female; Oligonucleotides; Muscular Atrophy, Spinal; Child; Child, Preschool; Adolescent; Republic of Korea; Adult; Infant; Treatment Outcome; Activities of Daily Living; Young Adult
PubMed: 38902631
DOI: 10.1186/s12883-024-03725-w -
TheScientificWorldJournal 2024Ethnomedicinally, more than 2000 plants were found to be used in Nepal. Among them, the red colored rhizome of and the bark of have been used widely to treat muscle...
Ethnomedicinally, more than 2000 plants were found to be used in Nepal. Among them, the red colored rhizome of and the bark of have been used widely to treat muscle fatigue, bone pain, fever, postpartum hemorrhage, and thirst by healers in Kaski and Tanahun districts, Nepal. However, scientific evidence towards their traditional uses is lacking till December, 2023. Therefore, we report the phytochemicals, total phenolic content (TPC), total flavonoid content (TFC), total carbohydrate content (TCC), antioxidant and antibacterial activities of and extracts. Phytochemical analysis indicated that and extracts were potential sources of chemicals such as phenols, flavonoids, tannins, terpenoids, saponins, and carbohydrates. The TPC, TFC, and TCC of extracts were determined by using an ultraviolet visible spectrophotometer. Among the extracts tested, extracts showed the highest phenolic and carbohydrate contents of 208.33 ± 12.96 mg of gallic acid equivalent/g and 564.16 ± 2.92 mg of D-glucose equivalent/g of dry extract, respectively. Similarly, revealed the highest flavonoid content of 30.35 ± 0.1 mg quercetin equivalent/g of dry extract. The extract of and exhibited potent antioxidant activity by scavenging 2,2-diphenyl-1-picrylhydrazyl radicals with an IC of 25.9 g/ml and 31.07 g/ml, respectively. The antibacterial activity of the and extract against , and was determined using an agar-well diffusion protocol that revealed the potential antibacterial activity of against . The present study will help validate the traditional uses of rhizomes and barks as a healing medicine and inspire the researcher towards further research, development, and formulation.
Topics: Antioxidants; Anti-Bacterial Agents; Plant Extracts; Phytochemicals; Plant Bark; Rhizome; Nepal; Flavonoids; Microbial Sensitivity Tests; Phenols
PubMed: 38898935
DOI: 10.1155/2024/1119165 -
Journal of Cellular and Molecular... Jun 2024Cancer-related fatigue (CRF) significantly impacts the quality of life of cancer patients. This study investigates the therapeutic potential of Shenqi Fuzheng injection...
Cancer-related fatigue (CRF) significantly impacts the quality of life of cancer patients. This study investigates the therapeutic potential of Shenqi Fuzheng injection (SFI) in managing CRF, focusing on its mechanistic action in skeletal muscle. We utilized a CRF mouse model to examine the effects of SFI on physical endurance, monitoring activity levels, swimming times and rest periods. Proteomic analysis of the gastrocnemius muscle was performed using isobaric tags and liquid chromatography-tandem mass spectrometry to map the muscle proteome changes post-SFI treatment. Mitochondrial function in skeletal muscle was assessed via ATP bioluminescence assay. Furthermore, the regulatory role of the hypoxia inducible factor 1 subunit alpha (HIF-1α) signalling pathway in mediating SFI's effects was explored through western blotting. In CRF-induced C2C12 myoblasts, we evaluated cell viability (CCK-8 assay), apoptosis (flow cytometry) and mitophagy (electron microscopy). The study also employed pulldown, luciferase and chromatin immunoprecipitation assays to elucidate the molecular mechanisms underlying SFI's action, particularly focusing on the transcriptional regulation of PINK1 through HIF-1α binding at the PINK1 promoter region. Our findings reveal that SFI enhances physical mobility, reduces fatigue symptoms and exerts protective effects on skeletal muscles by mitigating mitochondrial damage and augmenting antioxidative responses. SFI promotes cell viability and induces mitophagy while decreasing apoptosis, primarily through the modulation of HIF-1α, PINK1 and p62 proteins. These results underscore SFI's efficacy in enhancing mitochondrial autophagy, thereby offering a promising approach for ameliorating CRF. The study not only provides insight into SFI's potential therapeutic mechanisms but also establishes a foundation for further exploration of SFI interventions in CRF management.
Topics: Animals; Mitophagy; Drugs, Chinese Herbal; Muscle, Skeletal; Hypoxia-Inducible Factor 1, alpha Subunit; Mice; Ubiquitination; Neoplasms; Fatigue; Male; Apoptosis; Humans; Proteomics; Disease Models, Animal; Cell Line
PubMed: 38898772
DOI: 10.1111/jcmm.18455 -
Orthopaedic Journal of Sports Medicine Jun 2024Ulnar collateral ligament (UCL) injuries in youth pitchers continue to be concerning despite the institution of pitch count limits. Flexor-pronator mass fatigue can lead...
BACKGROUND
Ulnar collateral ligament (UCL) injuries in youth pitchers continue to be concerning despite the institution of pitch count limits. Flexor-pronator mass fatigue can lead to diminished dynamic stability, resulting in greater stress on the UCL.
PURPOSE/HYPOTHESIS
To evaluate fatigue of the flexor-pronator mass by assessing changes in medial elbow laxity; noninvasively characterizing alterations in muscle glycogen; and identifying changes in subjective fatigue, strength, range of motion (ROM), pitching velocity, and accuracy with increasing pitches thrown by youth pitchers to their recommended 75-pitch count limit. It was hypothesized that, with increased pitches, medial elbow laxity would increase and that the glycogen content of the flexor-pronator mass would decrease.
STUDY DESIGN
Descriptive laboratory study.
METHODS
Healthy male pitchers aged 10 years (n = 22) threw 3 sets of 25 pitches with 12 minutes between sets (3 timepoints). Bilateral ulnohumeral joint gapping was measured by applying a standardized valgus force and utilizing ultrasound imaging. Relative changes in muscle glycogen in the bilateral flexor carpi radialis (FCR), and the flexor digitorum superficialis/flexor carpi ulnaris (FDS/FCU) muscles were measured with ultrasound software and recorded as fuel percentiles. Additional measures obtained included subjective fatigue, strength, ROM, velocity, and accuracy.
RESULTS
There were no differences in medial elbow joint-line gapping between the throwing and nonthrowing arms or between timepoints. The throwing arm demonstrated a significant decline in fuel percentile of the FCR from baseline to after 75 pitches ( = .05). There were no differences across timepoints for FDS/FCU fuel percentile values. Fatigue measurements for both arms were significantly higher at all timepoints compared with baseline (≤ .03). Grip strength of the dominant arm after 75 pitches was decreased significantly compared with after 25 pitches ( = .02).
CONCLUSION
Although an increase in medial elbow joint gapping was not demonstrated within the recommended 75 pitch count limit in 10-year-olds, a relative decrease in glycogen stores of the flexor-pronator mass did occur, as well as a decrease in grip strength, with increasing subjective fatigue.
CLINICAL RELEVANCE
This study provides a foundation for further objective testing of physiologic changes that occur with pitching to better guide pitch count limits and improve the safety of young athletes.
PubMed: 38895136
DOI: 10.1177/23259671241256294 -
Sensors (Basel, Switzerland) May 2024This study introduces a novel wearable Inertial Measurement Unit (IMU)-based system for an objective and comprehensive assessment of Work-Related Musculoskeletal...
This study introduces a novel wearable Inertial Measurement Unit (IMU)-based system for an objective and comprehensive assessment of Work-Related Musculoskeletal Disorders (WMSDs), thus enhancing workplace safety. The system integrates wearable technology with a user-friendly interface, providing magnetometer-free orientation estimation, joint angle measurements, and WMSDs risk evaluation. Tested in a cable manufacturing facility, the system was evaluated with ten female employees. The evaluation involved work cycle identification, inter-subject comparisons, and benchmarking against standard WMSD risk assessments like RULA, REBA, Strain Index, and Rodgers Muscle Fatigue Analysis. The evaluation demonstrated uniform joint patterns across participants (ICC=0.72±0.23) and revealed a higher occurrence of postures warranting further investigation, which is not easily detected by traditional methods such as RULA. The experimental results showed that the proposed system's risk assessments closely aligned with the established methods and enabled detailed and targeted risk assessments, pinpointing specific bodily areas for immediate ergonomic interventions. This approach not only enhances the detection of ergonomic risks but also supports the development of personalized intervention strategies, addressing common workplace issues such as tendinitis, low back pain, and carpal tunnel syndrome. The outcomes highlight the system's sensitivity and specificity in identifying ergonomic hazards. Future efforts should focus on broader validation and exploring the relative influence of various WMSDs risk factors to refine risk assessment and intervention strategies for improved applicability in occupational health.
Topics: Humans; Musculoskeletal Diseases; Female; Risk Assessment; Wearable Electronic Devices; Adult; Occupational Diseases; Ergonomics; Posture; Workplace
PubMed: 38894211
DOI: 10.3390/s24113419 -
Journal of Clinical Medicine May 2024The most common post-acute consequences of SARS-CoV-2 include lung dysfunction, the impairment of cognitive functions and mental health, as well as the impairment of...
The most common post-acute consequences of SARS-CoV-2 include lung dysfunction, the impairment of cognitive functions and mental health, as well as the impairment of the musculoskeletal system in the form of fatigue and muscle weakness. Post-COVID-19 patients often experience impaired balance and reduced physical capacity. It is important to implement a rehabilitation program that eliminates the side effects of COVID-19 and allows for significant improvement in the patient's functionality. The aim of our study was to assess patient functionality after a 6-week rehabilitation program on balance, foot pressure distribution, and physical capacity in post-COVID-19 patients. The clinical study group consisted of 53 people 3 months after COVID-19 infection, confirmed by a positive PCR test. Exclusion from the study included people with comorbidities that impaired balance and gait. The patients underwent a posturographic assessment-Romberg test, a baropodometric assessment-static and dynamic, and a performance assessment-a 6 min walk test determining shortness of breath on the mMRC scale, blood pressure, heart rate, and saturation. Patients participated in rehabilitation until the sixth week, after which they were assessed again. Comparisons were made using IBM SPSS Statistics 27.0 software using the Wilcoxon pairwise order test, at a significance level of < 0.05. The result of the postural control assessment showed an improvement in the ability to maintain the centre of gravity in terms of the foot support area-statistical decreases were observed in the ellipse area, from 745.28 mm to 453.52 mm ( = 0.009), as well as maximum (from 3133.5 gr/cm to 2994.2 gr/cm; = 0.065) and average load on the left foot (from 1010.1 gr/cm to 969.38 gr/cm; = 0.028). In the 6 min walk test before and after exercise, the heart rate decreased after the therapy (shortness of breath on the mMRC scale also decreased from 79.12 to 74.95). This means that patients achieved better physical fitness and efficiency. Rehabilitation significantly improved balance, as measured by a decrease in ellipse area during the Romberg test
PubMed: 38892974
DOI: 10.3390/jcm13113257