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Scientific Reports Dec 2023The lumbopelvic muscle mechanical properties (MMPs) are clinically relevant, but their dependence on sex remains unknown. Therefore, this study aimed to identify if...
The lumbopelvic muscle mechanical properties (MMPs) are clinically relevant, but their dependence on sex remains unknown. Therefore, this study aimed to identify if lumbopelvic MMPs depend on the sex in a young adult population. Thirty-five healthy nulliparous women and 35 healthy men were analyzed (age range: 18-50). Lumbopelvic MMPs, that is, tone, stiffness, elasticity, relaxation and creep, assessed with MyotonPRO®, and pelvic floor (PF) health questionnaires were compared between-sexes. Intra-group correlations between sociodemographic and clinical data, and MMPs were also determined. The MMPs of PF were different between healthy non-climacteric adults of both sexes, with women showing higher values of tone and stiffness and lower values of elasticity and viscoelastic properties than men (in all cases, p < 0.03). At lumbar level, tone and stiffness were higher for men at both sides (in all cases, p < 0.04), and relaxation was lower at left side (p = 0.02). The MMPs showed few correlations with sociodemographic data within women. However, within males, there were positive correlations for PF stiffness and viscoelastic parameters with age, BMI and function (0.334 < r < 0.591) and, at lumbar level, negative correlations for tone and stiffness ( - 0.385 < r < -0.590) and positive correlations for viscoelastic properties (0.564 < r < 0.719), with BMI. This indicated that between-sexes differences of lumbopelvic MMPs depend on the specific location of assessment in healthy non-obese young individuals. Women show higher tone and stiffness and lower elasticity and viscoelasticity than men, at PF level.
Topics: Male; Young Adult; Humans; Female; Adolescent; Adult; Middle Aged; Cross-Sectional Studies; Musculoskeletal Physiological Phenomena; Lumbosacral Region; Muscle Tonus; Muscles
PubMed: 38062151
DOI: 10.1038/s41598-023-48984-8 -
Proceedings of the National Academy of... Jun 2012Skeletal muscle is widely perceived as nearly incompressible despite the fact that blood and lymphatic vessels within the endomysial and perimysial spaces undergo...
Skeletal muscle is widely perceived as nearly incompressible despite the fact that blood and lymphatic vessels within the endomysial and perimysial spaces undergo significant changes in diameter and length during stretch and contraction. These fluid shifts between fascicle and interstitial compartments have proved extremely difficult to measure. In this paper, we propose a theoretical framework based on a space-filling hexagonal fascicle array to provide predictions of the displacement of blood and lymph into and out of the muscle's endomysium and perimysium during stretch and contraction. We also use this model to quantify the distribution of blood and initial lymphatic (IL) vessels within a fascicle and its perimysial space using data for the rat spinotrapezius muscle. On average, there are 11 muscle fibers, 0.4 arteriole/venule pairs, and 0.2 IL vessels per fascicle. The model predicts that the blood volume in the endomysial space increases 24% and decreases 22% for a 20% contraction and stretch, respectively. However, these significant changes in blood volume in the endomysium produce a change of only ∼2% in fascicle cross-sectional area. In contrast, the entire muscle deviates from isovolumetry by 7% and 6% for a 20% contraction and stretch, respectively, largely attributable to the significantly larger blood volume changes that occur in the perimysial space. This suggests that arcade blood vessels in the perimysial space provide the primary pumping action required for the filling and emptying of ILs during muscular contraction and stretch.
Topics: Animals; Biomechanical Phenomena; Lymph; Models, Biological; Muscle Contraction; Muscle Tonus; Muscle, Skeletal; Rats; Regional Blood Flow
PubMed: 22615376
DOI: 10.1073/pnas.1206398109 -
PeerJ 2024The mechanical properties of muscles, such as changes in muscle tone and stiffness, are related to sports performance and injuries. Rowers are at increased risk of...
BACKGROUND
The mechanical properties of muscles, such as changes in muscle tone and stiffness, are related to sports performance and injuries. Rowers are at increased risk of muscle fatigue and injury during high-repetition and heavy-load cyclic muscle actions. In view of this, the aim of the present study was to investigate the acute effect on muscle tone and stiffness, as well as bilateral muscle asymmetry, in high school rowers after a 2000-meter rowing ergometer test.
METHODS
Twelve young male rowers (age = 17.1 ± 0.9 years, body weight = 73.5 ± 9.7 kg) were included in the study. The data of muscle tone (frequency) and stiffness of the posterior deltoids (PD), latissimus dorsi (LD), and rectus femoris (RF) (dominant and non-dominant side) before and after a 2000-m rowing ergometer test were collected using a handheld MyotonPRO device.
RESULTS
After the rowing ergometer test, the muscle tone of dominant side PD, LD, and RF were significantly increased ( < 0.05). On the other hand, the muscle stiffness of the non-dominant side LD and RF, as well as the dominant side PD, LD, and RF were significantly increased after the rowing ergometer test ( < 0.05). The muscle tone and stiffness results showed that the dominant side PD, LD, and RF were all significantly higher than the non-dominant side after the rowing ergometer test ( < 0.05), where bilateral PD and RF exhibits moderate asymmetry (5% < symmetry index < 10%).
CONCLUSIONS
After a high-intensity and high-load 2000-m rowing ergometer test, PD, LD, and RF showed increases in muscle tone and stiffness, as well as changes in the symmetry of bilateral muscle mechanical properties.
Topics: Male; Humans; Adolescent; Musculoskeletal Physiological Phenomena; Muscle Tonus; Muscle Fatigue; Quadriceps Muscle; Water Sports
PubMed: 38188161
DOI: 10.7717/peerj.16737 -
Amino Acids Aug 2013We examined the isolated and combined effects of beta-alanine (BA) and sodium bicarbonate (SB) on high-intensity intermittent upper-body performance in judo and... (Randomized Controlled Trial)
Randomized Controlled Trial
We examined the isolated and combined effects of beta-alanine (BA) and sodium bicarbonate (SB) on high-intensity intermittent upper-body performance in judo and jiu-jitsu competitors. 37 athletes were assigned to one of four groups: (1) placebo (PL)+PL; (2) BA+PL; (3) PL+SB or (4) BA+SB. BA or dextrose (placebo) (6.4 g day⁻¹) was ingested for 4 weeks and 500 mg kg⁻¹ BM of SB or calcium carbonate (placebo) was ingested for 7 days during the 4th week. Before and after 4 weeks of supplementation, the athletes completed four 30-s upper-body Wingate tests, separated by 3 min. Blood lactate was determined at rest, immediately after and 5 min after the 4th exercise bout, with perceived exertion reported immediately after the 4th bout. BA and SB alone increased the total work done in +7 and 8 %, respectively. The co-ingestion resulted in an additive effect (+14 %, p < 0.05 vs. BA and SB alone). BA alone significantly improved mean power in the 2nd and 3rd bouts and tended to improve the 4th bout. SB alone significantly improved mean power in the 4th bout and tended to improve in the 2nd and 3rd bouts. BA+SB enhanced mean power in all four bouts. PL+PL did not elicit any alteration on mean and peak power. Post-exercise blood lactate increased with all treatments except with PL+PL. Only BA+SB resulted in lower ratings of perceived exertion (p = 0.05). Chronic BA and SB supplementation alone equally enhanced high-intensity intermittent upper-body performance in well-trained athletes. Combined BA and SB promoted a clear additive ergogenic effect.
Topics: Acidosis; Adult; Athletes; Athletic Performance; Calcium Carbonate; Dietary Supplements; Double-Blind Method; Exercise Test; Humans; Lactic Acid; Male; Martial Arts; Motor Skills; Muscle Fatigue; Muscle Tonus; Physical Exertion; Sodium Bicarbonate; Upper Extremity; Young Adult; beta-Alanine
PubMed: 23595205
DOI: 10.1007/s00726-013-1495-z -
British Journal of Clinical Pharmacology Jul 19961. The ability to manipulate pharmacologically pulmonary vascular tone independent of effects on systemic blood vessels is a desirable objective. Elucidation of the... (Review)
Review
1. The ability to manipulate pharmacologically pulmonary vascular tone independent of effects on systemic blood vessels is a desirable objective. Elucidation of the biochemical mechanisms underlying hypoxia-induced pulmonary vasoconstriction (HPV) may permit preferential targeting of the pulmonary circulation. 2. Here we review our studies of the role of locally synthesized candidate vasoactive factors in HPV. In addition, we present data demonstrating an attenuated pressor response to hypoxia in the pulmonary circulation of Fischer 344 rats compared with the Wistar-Kyoto (WKY) rat strain. 3. We propose that a systematic genome-wide search using the HPV phenotype and a panel of highly informative microsatellite markers will elucidate the genetic loci underlying the difference in susceptibility to HPV in these two rat strains and provide a valuable and novel insight into the factors that determine the HPV response.
Topics: Animals; Muscle Tonus; Muscle, Smooth, Vascular; Pulmonary Circulation; Rats; Rats, Inbred F344; Rats, Inbred WKY; Vasoconstriction; Vasodilator Agents
PubMed: 8807153
DOI: 10.1046/j.1365-2125.1996.37117.x -
Clinical Interventions in Aging 2017This study aimed to determine whether excessive neck muscle tone affects hyoid bone kinetics during swallowing using videofluorography (VF) in an unnatural posture in...
PURPOSE
This study aimed to determine whether excessive neck muscle tone affects hyoid bone kinetics during swallowing using videofluorography (VF) in an unnatural posture in adults.
SUBJECTS AND METHODS
Subjects were 28 adults (12 men, 16 women; mean age, 39.75±9.50 years) who were suspected to have some symptom of swallowing disorders but did not have swallowing dysfunctional from the result of videofluorography. We first established the participant's posture a reclining wheelchair that was adjusted to a 30-degree angle with the headrest (without excessive neck muscle tone) or without headrest (with excessive neck muscle tone), used an electromyogram above the mylohyoid muscle to represent the suprahyoid muscles and above the sternohyoid muscle to represent the infrahyoid muscles to confirm neck muscle tone, and then conducted VF of swallowing measurements. Videofluorographic images were obtained when 5 mL of 50% (w/v) barium sulfate was being swallowed, and hyoid bone coordinate (the resting position and the elevated position), extent of horizontal and vertical hyoid bone elevation, as well as duration and velocity of hyoid bone elevation were evaluated (x-axis and y-axis coordinates for the resting position of hyoid bone are referred to as Xr and Yr, respectively; those for the elevated hyoid bone position induced during swallowing are referred to as Xs and Ys, respectively).
RESULTS
In the resting position of the hyoid bone, the Yr coordinates in those with excessive neck muscle tone were significantly lower than in those without excessive neck muscle tone. Vertical hyoid bone elevation and hyoid bone elevation velocity were significantly higher with excessive neck muscle tone than without excessive neck muscle tone, whereas horizontal elevation showed no significant differences.
CONCLUSION
Our findings suggest that the generation of neck muscle tone due to inappropriate posture may encourage hyoid depression and increase the extent of hyoid bone elevation, thereby increasing the risk of aspiration.
Topics: Adult; Deglutition; Electromyography; Female; Humans; Hyoid Bone; Kinetics; Male; Middle Aged; Muscle Tonus; Neck Muscles; Posture
PubMed: 29184396
DOI: 10.2147/CIA.S143175 -
BMC Oral Health May 2024The etiology of sleep bruxism in obstructive sleep apnea (OSA) patients is not yet fully clarified. This prospective clinical study aimed to investigate the connection...
BACKGROUND
The etiology of sleep bruxism in obstructive sleep apnea (OSA) patients is not yet fully clarified. This prospective clinical study aimed to investigate the connection between probable sleep bruxism, electromyographic muscle tone, and respiratory sleep patterns recorded during polysomnography.
METHODS
106 patients with OSA (74 males, 31 females, mean age: 56.1 ± 11.4 years) were divided into two groups (sleep bruxism: SB; no sleep bruxism: NSB). Probable SB were based on the AASM criteria: self-report of clenching/grinding, orofacial symptoms upon awakening, abnormal tooth wear and hypertrophy of the masseter muscle. Both groups underwent clinical examination for painful muscle symptoms aligned with Temporomandibular Disorders Diagnostic Criteria (DC/TMD), such as myalgia, myofascial pain, and headache attributed to temporomandibular disorder. Additionally, non-complaint positive muscle palpation and orofacial-related limitations (Jaw Functional Limited Scale-20: JFLS-20) were assessed. A one-night polysomnography with electromyographic masseter muscle tone (EMG) measurement was performed. Descriptive data, inter-group comparisons and multivariate logistic regression were calculated.
RESULTS
OSA patients had a 37.1% prevalence of SB. EMG muscle tone (N1-N3, REM; P = 0.001) and the number of hypopneas (P = 0.042) were significantly higher in the sleep bruxism group. While measures like apnea-hypopnea-index (AHI), respiratory-disturbance-index (RDI), apnea index (AI), hypopnea-index (HI), number of arousals, and heart rate (1/min) were elevated in sleep bruxers, the differences were not statistically significant. There was no difference in sleep efficiency (SE; P = 0.403). Non-complaint masseter muscle palpation (61.5%; P = 0.015) and myalgia (41%; P = 0.010) were significant higher in SB patients. Multivariate logistic regression showed a significant contribution of EMG muscle tone and JFLS-20 to bruxism risk.
CONCLUSION
Increased EMG muscle tone and orofacial limitations can predict sleep bruxism in OSA patients. Besides, SB patients suffer more from sleep disorder breathing. Thus, sleep bruxism seems to be not only an oral health related problem in obstructive apnea. Consequently, interdisciplinary interventions are crucial for effectively treating these patients.
TRIAL REGISTRATION
The study was approved by the Ethics Committee of Philipps-University Marburg (reg. no. 13/22-2022) and registered at the "German Clinical Trial Register, DRKS" (DRKS0002959).
Topics: Humans; Male; Female; Sleep Apnea, Obstructive; Sleep Bruxism; Middle Aged; Electromyography; Prospective Studies; Polysomnography; Masseter Muscle; Oral Health; Adult; Muscle Tonus
PubMed: 38745301
DOI: 10.1186/s12903-024-04351-1 -
Medicina (Kaunas, Lithuania) Sep 2019Functional electrical stimulation (FES) has shown good results in improving static and dynamic sitting balance in persons with spinal cord injuries. There is limited...
The Effect of Functional Electrical Stimulation and Therapeutic Exercises on Trunk Muscle Tone and Dynamic Sitting Balance in Persons with Chronic Spinal Cord Injury: A Crossover Trial.
Functional electrical stimulation (FES) has shown good results in improving static and dynamic sitting balance in persons with spinal cord injuries. There is limited information about how regular surface FES combined with therapeutic exercise (TE) affect dynamic sitting balance and muscle tone. The objective of this study was to evaluate the effectiveness of a six-week physical therapy program consisting of FES and TE on muscle tone and sitting balance in persons with spinal cord injury (SCI). It was also important to explore the relationship between muscle tone and dynamic sitting balance. The third objective was to assess the change of characteristics over a six month period, when no intervention was carried out. Five men with SCI were alternately allocated to two study groups: SCI_FES+TE and SCI_TE. Eight healthy control group participants were recruited to collect reference data. SCI participants' intervention lasted for six weeks in their homes. SCI_FES+TE conducted exercises with FES applied on erector spinae (ES) and rectus abdominis (RA) muscles. SCI_TE conducted exercises only. Muscle oscillation frequency (MOF; characterizing muscle tone) and limits of stability (LOS; characterizing sitting balance) were measured. A crossover study design was used. The time between the initial intervention and the crossover was seven months (ClinicalTrials registration ID NCT03517787). MOF in SCI_FES+TE increased by 6.0% for ES and 6.1% for RA muscles. LOS of flexion increased 30.1% in SCI_FES+TE. Increase in lateral directions was similar for both study groups. Moderate to high negative correlation was found between MOF and LOS. After seven months, MOF of ES decreased 0.8%, MOF or RA decreased 1.4%, LOS of flexion decreased 31.9%, and LOS of lateral flexion to the left decreased 46.4%. The six-week therapy program combining FES and TE increased trunk muscle tone and dynamic sitting balance in flexion more than TE alone. Higher antagonist muscle tone negatively affects dynamic sitting balance and center of pressure (COP) trajectory distance in various directions. After seven months, a slight decline in trunk muscles tone values and an extensive decrease in sitting balance values were noticed.
Topics: Adult; Case-Control Studies; Combined Modality Therapy; Cross-Over Studies; Electric Stimulation Therapy; Exercise Therapy; Humans; Male; Muscle Tonus; Postural Balance; Reference Values; Sitting Position; Spinal Cord Injuries
PubMed: 31546613
DOI: 10.3390/medicina55100619 -
The Journal of Neuroscience : the... Feb 2011Extraocular muscle tension associated with spontaneous eye movements has a pulse-slide-step profile similar to that of motoneuron firing rate. Existing models only...
Extraocular muscle tension associated with spontaneous eye movements has a pulse-slide-step profile similar to that of motoneuron firing rate. Existing models only relate motoneuron firing to eye position, velocity and acceleration. We measured and quantitatively compared lateral rectus muscle force and eye position with the firing of abducens motoneurons in the cat to determine fundamental encoding correlations. During fixations (step), muscle force increased exponentially with eccentric eye position, consistent with a model of estimate ensemble motor innervation based on neuronal sensitivities and recruitment order. Moreover, firing rate in all motoneurons tested was better related to eye position than to muscle tension during fixations. In contrast, during the postsaccadic slide phase, the time constant of firing rate decay was closely related to that of muscle force decay, suggesting that all motoneurons encode muscle tension as well. Discharge characteristics of abducens motoneurons formed overlapping clusters of phasic and tonic motoneurons, thus, tonic units recruited earlier and had a larger slide signal. We conclude that the slide signal is a discharge characteristic of the motoneuron that controls muscle tension during the postsaccadic phase and that motoneurons are specialized for both tension and position-related properties. The organization of signal content in the pool of abducens motoneurons from the very phasic to the very tonic units is possibly a result of the differential trophic background received from distinct types of muscle fibers.
Topics: Abducens Nerve; Action Potentials; Animals; Biomechanical Phenomena; Biophysics; Cats; Cluster Analysis; Electric Stimulation; Electromyography; Eye Movements; Female; Motor Neurons; Muscle Tonus; Oculomotor Muscles; Recruitment, Neurophysiological
PubMed: 21307263
DOI: 10.1523/JNEUROSCI.5416-10.2011 -
Schmerz (Berlin, Germany) Aug 2022Almost everyone is familiar with "tense muscles", but what is muscle tension physiologically behind? Are tense muscles more active; do they have problems relaxing? Are... (Review)
Review
Almost everyone is familiar with "tense muscles", but what is muscle tension physiologically behind? Are tense muscles more active; do they have problems relaxing? Are they harder or stiffer than asymptomatic muscles? In this work, current evidence regarding the activity and stiffness of tense neck muscles is presented. Further, measurement methods and their limitations are explained. These limitations reveal the shortcomings of the current knowledge and the need for further research. Finally, a recently funded research project on the measurement of tense muscles is presented.
Topics: Elasticity Imaging Techniques; Humans; Muscle Tonus; Muscle, Skeletal; Neck Muscles
PubMed: 35301591
DOI: 10.1007/s00482-022-00636-y