Measurement of muscle stiffness during a twitch contraction

1981 ◽

Vol 78 (3) ◽

pp. 295-311 ◽

Cited By ~ 153

Author(s):

F Parmiggiani ◽

R B Stein

Keyword(s):

Soleus Muscle ◽

Time Course ◽

Short Interval ◽

Force Production ◽

Muscle Stiffness ◽

Contraction Time ◽

Plantaris Muscle ◽

Twitch Contraction ◽

Slow Twitch ◽

Fast Twitch

The force produced by cat muscles over time with two stimuli separated by a short interval is approximately three times that produced by a twitch of cat muscles. This facilitation of force production by a second stimulus involves both increases in magnitude and duration of the contraction. Increased magnitude is relatively more important in the fast-twitch plantaris muscle, whereas increased duration is more important in the slow-twitch soleus muscle. The facilitation decays in an approximately exponential manner with the interval between stimuli, having a time constant between one and two times the twitch contraction time in different muscles. If a third stimulus is added, the greatest facilitation is seen at intervals longer than the twitch contraction time. The drug Dantrolene, which specifically reduces Ca++ release from the sarcoplasmic reticulum, eliminates the delayed peak in facilitation with three stimuli. Associated with the increases in force with one or more stimuli are increases in muscle stiffness, which can be measured with small, brief stretches and releases that do not alter the time-course of contraction. The stiffness of soleus muscle reaches a peak after the peak in force. The increasing stiffness of the muscle can considerably facilitate transmission of force generated internally, in addition to any facilitation arising from Ca++-release mechanisms.

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EFFECTS OF ADRENALINE, OUABAIN, AND SOME IONIC CONDITIONS ON TWITCH CONTRACTION OF BULLFROG VENTRICLE

The Japanese Journal of Physiology ◽

10.2170/jjphysiol.24.317 ◽

1974 ◽

Vol 24 (3) ◽

pp. 317-328 ◽

Cited By ~ 1

Author(s):

Tsuguhisa EHARA

Keyword(s):

Twitch Contraction

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Serum Creatine Kinase Increases after Acute Strength Training in College Athletes with Menstrual Irregularities

Women ◽

10.3390/women1020007 ◽

2021 ◽

Vol 1 (2) ◽

pp. 71-79

Author(s):

Akemi Sawai ◽

Risa Mitsuhashi ◽

Alexander Zaboronok ◽

Yuki Warashina ◽

Bryan J. Mathis

Keyword(s):

Creatine Kinase ◽

Strength Training ◽

College Athletes ◽

Biceps Femoris ◽

Muscle Stiffness ◽

Post Exercise ◽

Tendon Stiffness ◽

Menstrual Dysfunction ◽

Menstrual Irregularities ◽

Biceps Femoris Tendon

Chronic menstrual dysfunction and low female sex hormones adversely affect muscular performance in women but studies in college athletes are scarce. A cohort of 18 Japanese, female college athletes at the University of Tsukuba, Japan, were recruited and studied over 3 weeks under 2 conditions. One group had normal menstrual cycling (CYC, 9 athletes) while the other had irregular cycles (DYS, 9 athletes). Hormones and creatine kinase (CK) were measured from blood under both rest (RE) and exercise (EX) conditions. Biceps femoris tendon stiffness was measured by myometry. No differences in age, height, weight, menarche age, or one-repetition maximum weight existed between the groups. The DYS group had persistently low levels of estrogen and progesterone. In the CYC group, the CK level significantly increased at each point immediately post-exercise and 24 h post-exercise compared to pre-exercise in Weeks 1 and 2, and significantly increased at 24 h post-exercise compared to pre-exercise status in Week 3. The DYS group was significantly different only between pre-exercise and 24 h post-exercise over all 3 weeks. The DYS group also suffered from higher biceps femoris tendon stiffness at 24 h post-exercise. Chronic menstrual irregularities in Japanese college athletes increase muscle damage markers in the bloodstream and muscle stiffness after acute strength training.

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HINT1 neuropathy in Norway: clinical, genetic and functional profiling

Orphanet Journal of Rare Diseases ◽

10.1186/s13023-021-01746-z ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Silvia Amor-Barris ◽

Helle Høyer ◽

Lin V. Brauteset ◽

Els De Vriendt ◽

Linda Strand ◽

...

Keyword(s):

Axonal Neuropathy ◽

Functional Characterization ◽

Treatment Strategies ◽

Central Nervous System Involvement ◽

Sensory Neuropathy ◽

Muscle Stiffness ◽

Compound Heterozygous ◽

Clinical Genetic ◽

Cellular Models ◽

New Variant

Abstract Background Autosomal recessive axonal neuropathy with neuromyotonia has been linked to loss of functional HINT1. The disease is particularly prevalent in Central and South-East Europe, Turkey and Russia due to the high carrier frequency of the c.110G > C (p.Arg37Pro) founder variant. Results In a cohort of 748 Norwegian patients with suspected peripheral neuropathy, we identified two seemingly unrelated individuals, compound heterozygous for a new variant (c.284G > A, p.Arg95Gln) and the most common pathogenic founder variant (c.110G > C, p.Arg37Pro) in the HINT1 gene. Probands presented with motor greater than sensory neuropathy of various onset, accompanied by muscle stiffness and cramps in the limbs. Furthermore, they displayed non-classical symptoms, including pain in the extremities and signs of central nervous system involvement. Haplotype analysis in both patients revealed a common chromosomal background for p.Arg95Gln; moreover, the variant was identified in Swedish carriers. Functional characterization in HINT1-knockout and patient-derived cellular models, and in HNT1-knockout yeast, suggested that the new variant is deleterious for the function of HINT1 and provided mechanistic insights allowing patient stratification for future treatment strategies. Conclusion Our findings broaden the genetic epidemiology of HINT1-neuropathy and have implications for molecular diagnostics of inherited peripheral neuropathies in Scandinavia.

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The effects of 12 weeks of static stretch training on the functional, mechanical, and architectural characteristics of the triceps surae muscle–tendon complex

European Journal of Applied Physiology ◽

10.1007/s00421-021-04654-z ◽

2021 ◽

Author(s):

Stefano Longo ◽

Emiliano Cè ◽

Angela Valentina Bisconti ◽

Susanna Rampichini ◽

Christian Doria ◽

...

Keyword(s):

Muscle Activation ◽

Maximum Voluntary Contraction ◽

Muscle Stiffness ◽

Triceps Surae ◽

Maximum Force ◽

Passive Stiffness ◽

Electromechanical Delay ◽

Fascicle Length ◽

Generating Capacity ◽

Plantarflexor Muscles

Abstract Purpose We investigated the effects of 12 weeks of passive static stretching training (PST) on force-generating capacity, passive stiffness, muscle architecture of plantarflexor muscles. Methods Thirty healthy adults participated in the study. Fifteen participants (STR, 6 women, 9 men) underwent 12-week plantarflexor muscles PST [(5 × 45 s-on/15 s-off) × 2exercises] × 5times/week (duration: 2250 s/week), while 15 participants (CTRL, 6 women, 9 men) served as control (no PST). Range of motion (ROM), maximum passive resistive torque (PRTmax), triceps surae architecture [fascicle length, fascicle angle, and thickness], passive stiffness [muscle–tendon complex (MTC) and muscle stiffness], and plantarflexors maximun force-generating capacity variables (maximum voluntary contraction, maximum muscle activation, rate of torque development, electromechanical delay) were calculated Pre, at the 6th (Wk6), and the 12th week (Wk12) of the protocol in both groups. Results Compared to Pre, STR ROM increased (P < 0.05) at Wk6 (8%) and Wk12 (23%). PRTmax increased at Wk12 (30%, P < 0.05), while MTC stiffness decreased (16%, P < 0.05). Muscle stiffness decreased (P < 0.05) at Wk6 (11%) and Wk12 (16%). No changes in triceps surae architecture and plantarflexors maximum force-generating capacity variables were found in STR (P > 0.05). Percentage changes in ROM correlated with percentage changes in PRTmax (ρ = 0.62, P = 0.01) and MTC stiffness (ρ = − 0.78, P = 0.001). In CTRL, no changes (P > 0.05) occurred in any variables at any time point. Conclusion The expected long-term PST-induced changes in ROM were associated with modifications in the whole passive mechanical properties of the ankle joint, while maximum force-generating capacity characteristics were preserved. 12 weeks of PST do not seem a sufficient stimulus to induce triceps surae architectural changes.

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The effect of dry needling of myofascial trigger points on muscle stiffness and motoneuron excitability in healthy subjects

Acupuncture in Medicine ◽

10.1177/09645284211027579 ◽

2021 ◽

pp. 096452842110275

Author(s):

Carolina Jiménez-Sánchez ◽

Julio Gómez-Soriano ◽

Elisabeth Bravo-Esteban ◽

Orlando Mayoral-del Moral ◽

Pablo Herrero-Gállego ◽

...

Keyword(s):

Muscle Tone ◽

Intervention Group ◽

Trigger Points ◽

Muscle Stiffness ◽

Invasive Technique ◽

Control Group ◽

Dry Needling ◽

Myofascial Trigger Points ◽

Motoneuron Excitability

Background: Myofascial trigger points (MTrPs) are hypersensitive nodules in a taut band (TB) of skeletal muscle. Dry needling (DN) is an invasive technique recommended for the treatment of MTrPs. However, to our knowledge, no studies have investigated the influence of the DN technique on modification of muscle stiffness and neurophysiological properties of MTrPs. Objective: The objective was to examine the effect of DN on muscle stiffness and motoneuron excitability of a latent medial MTrP (nodule and TB) of the soleus muscle in non-injured subjects. Methods: A double-blinded randomised controlled trial of 46 subjects with latent medial MTrPs of the soleus was conducted, in which all received one session of DN. The intervention group (n = 23) were subjected to DN into the MTrP (the nodule), while the control group (n = 23) were subjected to DN into the TB. Assessment was carried out at baseline (pre-test), after the intervention (post-test) and 1 week after the intervention (follow-up). Biomechanical variables (muscle resistive force at 10°/s and 180°/s, muscle extensibility and strength), as measured with an isokinetic dynamometer, and neurophysiological variables (H-reflex), were recorded. Results: There were no statistically significant differences in biomechanical or neurophysiological assessments between groups. Considering the intra-group analysis, subjects in the intervention group exhibited increased maximal isometric voluntary force to ankle plantarflexion (MIVFp) at both post-intervention and follow-up assessment (p < 0.0125; 0.2 < d < 0.5), while no changes were found in the control group. Conclusion: One session of DN targeting latent MTrPs did not change muscle stiffness, muscle extensibility or motoneuron excitability. Further research on subjects with muscle tone disorders should be considered to better address the impact of DN on muscle tone. Trial registration number: NCT02575586 (ClinicalTrials.gov).

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Moderate-duration static stretch reduces active and passive plantar flexor moment but not Achilles tendon stiffness or active muscle length

Journal of Applied Physiology ◽

10.1152/japplphysiol.91476.2008 ◽

2009 ◽

Vol 106 (4) ◽

pp. 1249-1256 ◽

Cited By ~ 91

Author(s):

Anthony D. Kay ◽

Anthony J. Blazevich

Keyword(s):

Mechanical Properties ◽

Achilles Tendon ◽

Muscle Stiffness ◽

Triceps Surae ◽

Medial Gastrocnemius ◽

Static Stretch ◽

Tendon Stiffness ◽

Neuromuscular Activity ◽

Time Motion ◽

The Impact

The effects of static stretch on muscle and tendon mechanical properties and muscle activation were studied in fifteen healthy human volunteers. Peak active and passive moment data were recorded during plantar flexion trials on an isokinetic dynamometer. Electromyography (EMG) monitoring of the triceps surae muscles, real-time motion analysis of the lower leg, and ultrasound imaging of the Achilles-medial gastrocnemius muscle-tendon junction were simultaneously conducted. Subjects performed three 60-s static stretches before being retested 2 min and 30 min poststretch. There were three main findings in the present study. First, peak concentric moment was significantly reduced after stretch; 60% of the deficit recovered 30 min poststretch. This was accompanied by, and correlated with ( r = 0.81 ; P < 0.01) reductions in peak triceps surae EMG amplitude, which was fully recovered at 30 min poststretch. Second, Achilles tendon length was significantly shorter during the concentric contraction after stretch and at 30 min poststretch; however, no change in tendon stiffness was detected. Third, passive joint moment was significantly reduced after stretch, and this was accompanied by significant reductions in medial gastrocnemius passive muscle stiffness; both measures fully recovered by 30 min poststretch. These data indicate that the stretching protocol used in this study induced losses in concentric moment that were accompanied by, and related to, reductions in neuromuscular activity, but they were not associated with alterations in tendon stiffness or shorter muscle operating length. Reductions in passive moment were associated with reductions in muscle stiffness, whereas tendon mechanics were unaffected by the stretch. Importantly, the impact on mechanical properties and neuromuscular activity was minimal at 30 min poststretch.

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