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Archives of Gerontology and Geriatrics 2016Age and gender effects on muscle tone and mechanical properties have not been studied using hand-held myometric technology. Monitoring changes in muscle properties with... (Comparative Study)
Comparative Study
Measurement of ageing effects on muscle tone and mechanical properties of rectus femoris and biceps brachii in healthy males and females using a novel hand-held myometric device.
BACKGROUND
Age and gender effects on muscle tone and mechanical properties have not been studied using hand-held myometric technology. Monitoring changes in muscle properties with ageing in community settings may provide a valuable assessment tool for detecting those at risk of premature decline and sarcopenia.
OBJECTIVE
This study aimed to provide objective data on the effects of ageing and gender on muscle tone and mechanical properties of quadriceps (rectus femoris) and biceps brachii muscles.
METHODS
In a comparative study of 123 healthy males and females (aged 18-90 years; n=61 aged 18-35; n=62 aged 65-90) muscle tone, elasticity and stiffness were measured using the MyotonPRO device.
RESULTS
Stiffness was greater and elasticity lower in older adults for BB and RF (p<0.001). Tone was significantly greater in older adults for BB but not for RF when data for males and females were combined (p=0.28). There were no gender differences for BB in either age group. In RF, males had greater stiffness (young males 292 vs females 233 N/m; older males 328 vs females 311 N/m) and tone (young 16.4 vs 13.6 Hz; older 16.7 vs 14.9 Hz). Elasticity in RF was lower in young males than females but did not differ between the older groups (both males and females log decrement 1.6).
CONCLUSIONS
Stiffness and tone increased with ageing and elasticity decreased. These findings have implications for detecting frailty using a novel biomarker. Age and gender differences are important to consider when assessing effects of pathological conditions on muscle properties in older people.
Topics: Adult; Age Factors; Aged; Aged, 80 and over; Aging; Elasticity; Female; Geriatric Assessment; Humans; Male; Middle Aged; Muscle Tonus; Muscle, Skeletal; Quadriceps Muscle; Reproducibility of Results; Sex Factors; Stress, Mechanical; Young Adult
PubMed: 26476868
DOI: 10.1016/j.archger.2015.09.011 -
Journal of Applied Physiology... Aug 2003Previous studies have suggested that activation of ATP-sensitive P2X receptors in skeletal muscle play a role in mediating the exercise pressor reflex (Li J and Sinoway...
Previous studies have suggested that activation of ATP-sensitive P2X receptors in skeletal muscle play a role in mediating the exercise pressor reflex (Li J and Sinoway LI. Am J Physiol Heart Circ Physiol 283: H2636-H2643, 2002). To determine the role ATP plays in this reflex, it is necessary to examine whether muscle interstitial ATP (ATPi) concentrations rise with muscle contraction. Accordingly, in this study, muscle contraction was evoked by electrical stimulation of the L7 and S1 ventral roots of the spinal cord in 12 decerebrate cats. Muscle ATPi was collected from microdialysis probes inserted in the muscle. ATP concentrations were determined by the HPLC method. Electrical stimulation of the ventral roots at 3 and 5 Hz increased mean arterial pressure by 13 +/- 2 and 16 +/- 3 mmHg (P < 0.05), respectively, and it increased ATP concentration in contracting muscle by 150% (P < 0.05) and 200% (P < 0.05), respectively. ATP measured in the opposite control limb did not rise with ventral root stimulation. Section of the L7 and S1 dorsal roots did not affect the ATPi seen with 5-Hz ventral root stimulation. Finally, ventral roots stimulation sufficient to drive motor nerve fibers did not increase ATP in previously paralyzed cats. Thus ATPi is not largely released from sympathetic or motor nerves and does not require an intact afferent reflex pathway. We conclude that ATPi is due to the release of ATP from contracting skeletal muscle cells.
Topics: Adenosine Triphosphate; Animals; Cats; Denervation; Electric Stimulation; Lumbosacral Region; Male; Microdialysis; Muscle Contraction; Muscle Tonus; Muscle, Skeletal; Osmolar Concentration; Paralysis; Spinal Nerve Roots
PubMed: 12716867
DOI: 10.1152/japplphysiol.00185.2003 -
Journal of Visualized Experiments : JoVE Jan 2016Multiple approaches have been used to record and evaluate gastrointestinal motility including: recording changes in muscle tension, intraluminal pressure, and membrane...
Multiple approaches have been used to record and evaluate gastrointestinal motility including: recording changes in muscle tension, intraluminal pressure, and membrane potential. All of these approaches depend on measurement of activity at one or multiple locations along the gut simultaneously which are then interpreted to provide a sense of overall motility patterns. Recently, the development of video recording and spatiotemporal mapping (STmap) techniques have made it possible to observe and analyze complex patterns in ex vivo whole segments of colon and intestine. Once recorded and digitized, video records can be converted to STmaps in which the luminal diameter is converted to grayscale or color [called diameter maps (Dmaps)]. STmaps can provide data on motility direction (i.e., stationary, peristaltic, antiperistaltic), velocity, duration, frequency and strength of contractile motility patterns. Advantages of this approach include: analysis of interaction or simultaneous development of different motility patterns in different regions of the same segment, visualization of motility pattern changes over time, and analysis of how activity in one region influences activity in another region. Video recordings can be replayed with different timescales and analysis parameters so that separate STmaps and motility patterns can be analyzed in more detail. This protocol specifically details the effects of intraluminal fluid distension and intraluminal stimuli that affect motility generation. The use of luminal receptor agonists and antagonists provides mechanistic information on how specific patterns are initiated and how one pattern can be converted into another pattern. The technique is limited by the ability to only measure motility that causes changes in luminal diameter, without providing data on intraluminal pressure changes or muscle tension, and by the generation of artifacts based upon experimental setup; although, analysis methods can account for these issues. When compared to previous techniques the video recording and STmap approach provides a more comprehensive understanding of gastrointestinal motility.
Topics: Animals; Colon; Guinea Pigs; Muscle Contraction; Muscle Tonus; Peristalsis; Pressure; Video Recording
PubMed: 26863156
DOI: 10.3791/53263 -
The British Journal of Ophthalmology Dec 2002
Review
Topics: Animals; Hemianopsia; Humans; Infant, Newborn; Movement; Muscle Tonus; Phototropism; Posture; Reflex; Torticollis; Vision Disorders
PubMed: 12446357
DOI: 10.1136/bjo.86.12.1327 -
Journal of Neurophysiology May 2002Orexins/hypocretins are synthesized in neurons of the perifornical, dorsomedial, lateral, and posterior hypothalamus. A loss of hypocretin neurons has been found in...
Orexins/hypocretins are synthesized in neurons of the perifornical, dorsomedial, lateral, and posterior hypothalamus. A loss of hypocretin neurons has been found in human narcolepsy, which is characterized by sudden loss of muscle tone, called cataplexy, and sleepiness. The normal functional role of these neurons, however, is unclear. The medioventral medullary region, including gigantocellular reticular nucleus, alpha (GiA) and ventral (GiV) parts, participates in the induction of locomotion and muscle tone facilitation in decerebrate animals and receives moderate orexinergic innervation. In the present study, we have examined the role of orexin-A (OX-A) in muscle tone control using microinjections (50 microM, 0.3 microl) into the GiA and GiV sites in decerebrate rats. OX-A microinjections into GiA sites, previously identified by electrical stimulation as facilitating hindlimb muscle tone bilaterally, produced a bilateral increase of muscle tone in the same muscles. Bilateral lidocaine microinjections (4%, 0.3 microl) into the dorsolateral mesopontine reticular formation decreased muscle rigidity and blocked muscle tone facilitation produced by OX-A microinjections into the GiA sites. The activity of cells related to muscle rigidity, located in the pedunculopontine tegmental nucleus and adjacent reticular formation, was correlated positively with the extent of hindlimb muscle tone facilitation after medullary OX-A microinjections. OX-A microinjections into GiV sites were less effective in muscle tone facilitation, although these sites produced a muscle tone increase during electrical stimulation. In contrast, OX-A microinjections into the gigantocellular nucleus (Gi) sites and dorsal paragigantocellular nucleus (DPGi) sites, previously identified by electrical stimulation as inhibitory points, produced bilateral hindlimb muscle atonia. We propose that the medioventral medullary region is one of the brain stem target for OX-A modulation of muscle tone. Facilitation of muscle tone after OX-A microinjections into this region is linked to activation of intrinsic reticular cells, causing excitation of midbrain and pontine neurons participating in muscle tone facilitation through an ascending pathway. Moreover, our results suggest that OX-A may also regulate the activity of medullary neurons participating in muscle tone suppression. Loss of OX function may, therefore, disturb both muscle tone facilitatory and inhibitory processes at the medullary level.
Topics: Anesthetics, Local; Animals; Carrier Proteins; Electric Stimulation; Electromyography; Intracellular Signaling Peptides and Proteins; Lidocaine; Medulla Oblongata; Mesencephalon; Microinjections; Muscle Tonus; Muscle, Skeletal; Neuropeptides; Orexins; Pons; Rats; Rats, Wistar; Reticular Formation; Sympathomimetics
PubMed: 11976385
DOI: 10.1152/jn.2002.87.5.2480 -
Respiratory Research 2001Obstructive sleep apnoea is a common and serious breathing problem that is caused by effects of sleep on pharyngeal muscle tone in individuals with narrow upper airways.... (Review)
Review
Obstructive sleep apnoea is a common and serious breathing problem that is caused by effects of sleep on pharyngeal muscle tone in individuals with narrow upper airways. There has been increasing focus on delineating the brain mechanisms that modulate pharyngeal muscle activity in the awake and asleep states in order to understand the pathogenesis of obstructive apnoeas and to develop novel neurochemical treatments. Although initial clinical studies have met with only limited success, it is proposed that more rational and realistic approaches may be devised for neurochemical modulation of pharyngeal muscle tone as the relevant neurotransmitters and receptors that are involved in sleep-dependent modulation are identified following basic experiments.
Topics: Animals; Humans; Muscle Tonus; Pharyngeal Muscles; Respiratory Muscles; Respiratory System; Sleep; Sleep Apnea, Obstructive; Wakefulness
PubMed: 11686898
DOI: 10.1186/rr71 -
Experimental Physiology May 1991Resting muscle tone of the leg was measured in terms of thigh muscle stiffness and knee resonant frequency in muscles of spinal cord injured subjects who had been...
Resting muscle tone of the leg was measured in terms of thigh muscle stiffness and knee resonant frequency in muscles of spinal cord injured subjects who had been involved in an electrical neuromuscular stimulation training programme of the thigh muscles over at least 2 months. The thigh circumference of these patients was 6.6% larger than before training commenced (P less than 0.001) and showed increased muscle stiffness and resonant frequency compared to a similar group of paralysed subjects who had not used any neuromuscular stimulation. Resonant frequency and stiffness after the long-term training were similar to those of non-injured controls and therefore the stimulation programme seemed to reverse the effects of paralysis on muscle tone. Short periods of rest (30 min) caused increased muscle stiffness in non-injured controls and paralysed muscles trained by neuromuscular stimulation. Additional 15 min periods of neuromuscular stimulation further increased muscle stiffness in the trained muscles but also in the muscles of paralysed subjects who had no long-term neuromuscular training. In contrast, 15 min sessions of passive movement of the knee decreased muscle stiffness in long-term trained paralysed muscles and untrained paralysed muscles. Knee resonant frequency was also significantly decreased in the trained paralysed muscles. Results show that muscle tone varies depending on the amount of previous movement or rest and that although neuromuscular stimulation of paralysed muscles increases muscle stiffness and knee resonant frequency, it is in fact restoring such properties of the muscle to a state approaching that of non-injured controls.
Topics: Adult; Electric Stimulation Therapy; Exercise; Humans; Knee Joint; Muscle Relaxation; Muscle Rigidity; Muscle Spasticity; Muscle Tonus; Neuromuscular Junction; Paralysis; Paraplegia; Spinal Cord Injuries
PubMed: 1878193
DOI: 10.1113/expphysiol.1991.sp003503 -
Medical Science Monitor : International... Jul 2020BACKGROUND Contracture is related to modulation of passive stiffness in muscle and tendon after spinal cord injury (SCI). Current clinical assessments of stiffness in...
BACKGROUND Contracture is related to modulation of passive stiffness in muscle and tendon after spinal cord injury (SCI). Current clinical assessments of stiffness in muscles and tendons are subjective in patients with spinal cord injury. We proposed a quantitative method to evaluate stiffness of the gastrocnemius and Achilles tendon (AT) with a portable device, the MyotonPRO. The purpose of this study was to investigate the intraoperator and interoperator reliability of the MyotonPRO when used in patients after spinal cord injury. MATERIAL AND METHODS Fourteen patients with SCI participated in this study. Gastrocnemius stiffness and AT stiffness were measured with the MyotonPRO. RESULTS In participants with SCI, the intraclass correlation coefficient (ICC) values for intraoperator and interoperator reliability of stiffness measurements in the gastrocnemius and AT were excellent (all ICC >0.87), with relatively low values for standard error measurement (SEM) and minimal detectable change (MDC). CONCLUSIONS Our findings suggest that use of the MyotonPRO is feasible for evaluating stiffness of the gastrocnemius and AT in the lower limbs of patients with spinal cord injury.
Topics: Achilles Tendon; Adolescent; Adult; Aged; Ankle Joint; Biomechanical Phenomena; Female; Humans; Male; Middle Aged; Muscle Strength; Muscle Tonus; Muscle, Skeletal; Range of Motion, Articular; Reproducibility of Results; Spinal Cord Injuries
PubMed: 32719308
DOI: 10.12659/MSM.924811 -
Brain Research Mar 1992The dorsolateral pontine inhibitory area (PIA) and medial medullary reticular formation (MMRF) have been found to mediate the muscle atonia of REM sleep. Our previous...
The dorsolateral pontine inhibitory area (PIA) and medial medullary reticular formation (MMRF) have been found to mediate the muscle atonia of REM sleep. Our previous studies have shown that acetylcholine (ACh) microinjection in the PIA and in the nucleus paramedianus of the medial medulla produces muscle atonia. Glutamate microinjection in both PIA and nucleus magnocellularis (NMC) of the medial medulla also produces muscle atonia. Since immunohistochemical studies have identified corticotropin-releasing factor (CRF) as a potential dorsolateral pontine and NMC transmitter, the present study was undertaken to determine whether this transmitter could produce suppression of muscle tone. Experiments were performed on unanesthetized, decerebrated cats. CRF was microinjected into points in the PIA and NMC at which electrical stimulation produced bilateral inhibition of muscle tone. We found that CRF produced a dose-dependent muscle tone suppression. At 10 nM concentration, the latency and duration of muscle inhibition produced by CRF injection were comparable with those of L-glutamate, at 18.8 s and 4.1 min, respectively. This CRF-induced muscle inhibition was blocked by the CRF antagonist, alpha-helical [Glu27]corticotropin-releasing factor 9-41 (CRF 9-41). Microinjection of CRF and non-NMDA agonists, kainate and quisqualate, into the same sites in PIA and NMC produced muscle atonia. Pontine sites at which CRF injection induces atonia are identical to those at which acetylcholine microinjection produces atonia. These results indicate that CRF may interact with glutamate and acetylcholine in the generation of muscle atonia.
Topics: Animals; Cats; Corticotropin-Releasing Hormone; Electric Stimulation; Female; Male; Medulla Oblongata; Microinjections; Muscle Tonus; Pons; Sleep, REM
PubMed: 1504782
DOI: 10.1016/0006-8993(92)90423-7 -
Clinical Biomechanics (Bristol, Avon) Jan 2016Individuals with cerebral palsy tend to have altered muscle architecture and composition, but little is known about the muscle material properties, specifically...
BACKGROUND
Individuals with cerebral palsy tend to have altered muscle architecture and composition, but little is known about the muscle material properties, specifically stiffness. Shear wave ultrasound elastography allows shear wave speed, which is related to stiffness, to be measured in vivo in individual muscles. Our aim was to evaluate the material properties, specifically stiffness, as measured by shear wave speed of the medial gastrocnemius and tibialis anterior muscles in children with hemiplegic cerebral palsy across a range of ankle torques and positions, and fascicle strains.
METHOD
Shear wave speed was measured bilaterally in the medial gastrocnemius and tibialis anterior over a range of ankle positions and torques using shear wave ultrasound elastography in eight individuals with hemiplegic cerebral palsy. B-mode ultrasound was used to measure muscle thickness and fascicle strain.
RESULTS
Shear waves traveled faster in the medial gastrocnemius and tibialis anterior of the more-affected limb by 14% (P=0.024) and 20% (P=0.03), respectively, when the ankle was at 90°. Shear wave speed in the medial gastrocnemius increased as the ankle moved from plantarflexion to dorsiflexion (less affected: r(2)=0.82, P<0.001; more-affected: r(2)=0.69, P<0.001) and as ankle torque increased (less affected: r(2)=0.56, P<0.001; more-affected: r(2)=0.45, P<0.001). In addition, shear wave speed was strongly correlated with fascicle strain (less affected: r(2)=0.63, P<0.001; more-affected: r(2)=0.53, P<0.001).
INTERPRETATION
The higher shear wave speed in the more-affected limb of individuals with cerebral palsy indicates greater muscle stiffness, and demonstrates the clinical potential of shear wave elastography as a non-invasive tool for investigating mechanisms of altered muscle properties and informing diagnosis and treatment.
Topics: Analysis of Variance; Ankle Joint; Cerebral Palsy; Child; Elasticity Imaging Techniques; Female; Humans; Male; Muscle Tonus; Muscle, Skeletal; Musculoskeletal Physiological Phenomena
PubMed: 26490641
DOI: 10.1016/j.clinbiomech.2015.10.006