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This study aimed to evaluate changes in muscle contractile properties during a training microcycle in semi-professional female football players and explore their relationship with training load variables. Nineteen players (age: 23.9 ± 3.9 years; body mass: 60.6 ± 6.9 kg; height: 164.5 ± 6.7 cm) underwent myotonometric assessments of the biceps femoris (BF) and rectus femoris (RF) before and after the following training sessions: MD1 (i.e., 1 day after the match), MD3, MD4, and MD5. Training loads were quantified for each session, revealing significant variations, with MD4 exhibiting the highest values for high-speed running distance, number of sprints, and accelerations. Notably, MD3 showed the highest perceived exertion (RPE), while MD5 recorded the lowest total distance run. Myotonometric assessments indicated significant differences in stiffness of the RF in MD3 and BF in MD5, as well as RF tone in MD5. The findings underscore a notable relationship between training load and myotometric variables, particularly in muscle stiffness and tone. These results emphasize the need for further research to clarify how training loads affect muscle properties in female athletes. [ABSTRACT FROM AUTHOR]

Background: Biomechanical muscle properties, such as stiffness, can be valuable indicators of tissue health and show promise as a diagnostic and treatment measure for chronic low back pain (CLBP). The development of accessible assessment technologies, such as the MyotonPRO portable device, allows for the convenient quantification of muscle tone and stiffness changes. The aim of this study is to assess the reliability of lumbar erector spinae muscle stiffness with the MyotonPRO in healthy adults and to compare stiffness changes between prone and sitting position. Methods: Thirty asymptomatic participants (N = 15 women and N = 15 men) aged between 18 and 65 years were recruited to participate in this study. Two examiners tested muscle stiffness at the palpable muscle belly, one finger away from the spinous process at the level of the L4 vertebra, first from the left and then from the right side, both in prone position and after in sitting position. For inter-rater reliability, all participants were tested by two examiners on the same day, and intra-rater reliability was calculated using the same examiner's assessment results with an exact 24-h interval. Intraclass correlation coefficients (ICC), standard error measures (SEM) and minimum detectable change (MDC) with a 95% confidence interval were calculated to assess intra-rater and inter-rater reliability. Results: Statistical analysis revealed good intra-rater reliability with an ICC of 0.88 (95% CI [0.76–0.94]) for the stiffness of the left erector spinae and excellent intra-rater reliability with an ICC of 0.91 (95% CI [0.82–0.95]) for the right erector spinae, both in the prone position. Intra-rater reliability in the sitting position was excellent to very good with an ICC of 0.91 (95% CI [0.82–0.96]) for the left side and an ICC of 0.89 (95% CI [0.78–0.95]) for the right side. The results for the left-sided prone position showed good inter-rater reliability with an ICC of 0.87 (95% CI [0.73–0.94]). The prone position on the right side also showed good inter-rater reliability with an ICC of 0.84 (95% CI [0.68–0.92]). The inter-rater reliability for the left and right side in the sitting position was excellent with an ICC of 0.96 (95% CI [0.92–0.98]) for the left side and an ICC of 0.95 (95% CI [0.90–0.97]) for the right side. Conclusion: This study demonstrated high reliability in measuring lumbar erector spinae muscle stiffness with the MyotonPRO in healthy adults and the ability of the device to detect even small changes in erector spinae muscle stiffness, testing both the right and left sides and measuring in both prone and sitting positions. The use of the sitting position to assess lumbar tissue tension in individuals may serve as a valuable substitute for the prone position, particularly for patients who experience discomfort in the prone position, and could have additional practical significance in clinical settings. [ABSTRACT FROM AUTHOR]

Context: The research on the change in properties of the lower leg muscles by different intensity sinusoidal vertical whole-body vibration ( SV - WBV ) exposures has not yet been investigated. Objective: The purpose of this study was to determine effect of a 20-minute different intensity SV-WBV application to the ankle plantar flexor and dorsiflexor muscles properties and hamstring flexibility. Design: Prospective preintervention -postintervention design. Setting: Physiotherapy department. Participants: A total of 50 recreationally active collegeaged individuals with no history of a lower leg injury volunteered. Interventions: The SV-WBV was applied throughout the session with an amplitude of 2 to 4 mm and a frequency of 25 Hz in moderate-intensity vibration group and 40 Hz in a vigorousintensity vibration group . Main Outcome Measures : The gastrocnemius and tibialis anterior muscle tone was assessed with MyotonPRO, and the strength evaluation was made on the same lower leg muscles using hand-held dynamometer. The sit and reach test was used for the lower leg flexibility evaluation. Results: The gastrocnemius muscle tone decreased on the right side (d = 0.643, P = .01) and increased on the left (d= 0.593, P = .04) when vigorous-intensity vibration was applied. Bilateral gastrocnemius muscle strength did not change in both groups (P >.05). Without differences between groups, bilateral tibialis anterior muscle strength increased in both groups (P < .01). B ilateral gastrocnemius and tibialis anterior muscle tone did not change in the moderate-intensity vibration group (P> .05). Flexibility increased in both groups (P < . 01 ); however, there was no statistically significant difference between the groups ( d = 0 . 169, P = . 55 ). Conclusions: According to study results, if SV-WBV is to be used in hamstring flexibility or ankle dorsiflexor muscle strengthening, both vibration exposures should be preferred. Different vibration programs could be proposed to increase ankle plantar Rexor muscle strength in the acute results. Vigorous-intensity vibration exposure is effective in altering ankle plantar flexor muscle tone, but it is important to be aware of the differences between the lower legs. [ABSTRACT FROM AUTHOR]

BACKGROUND: As a local vibration therapy, deep muscle stimulation therapy can relieve pain and loose fascia adhesion through a specific frequency of mechanical wave by hitting pain points, but less is reported on the changes of muscle tone and stiffness of erector spinaes after its effect on chronic nonspecific low back pain. OBJECTIVE: To observe the effect of deep muscle stimulation on muscle tone and stiffness of erector spinaes as well as clinical efficacy in patients with chronic non-specific low back pain by a digital muscle detector. METHODS: A total of 60 patients with chronic non-specific low back pain admitted to the First Affiliated Hospital of Guangdong Pharmaceutical University from September 2019 to June 2021 were enrolled and randomly divided into two groups (n=30 per group): a control group and an experimental group. Patients in the control group received the routine physical therapies, including core muscle group practice, stereodynamic interference electrotherapy and health education, and patients in the experimental group received deep muscle stimulation therapy based on the routine physical therapies, five times per week, for 4 consecutive weeks. Pain degree, waist function, changes of muscle tone and stiffness of the erector spinae muscle, and clinical efficacy were statistically analyzed before treatment, after the first treatment, after the completion of all treatments, and 4 weeks after treatment. RESULTS AND CONCLUSION: After the first treatment, the oscillation frequency (F value), visual analog scale scores and stiffness values of the two groups were significantly lowered (P < 0.05), except for the oscillation frequency of the control group (P > 0.05). After the completion of all treatments, the visual analog scale scores, oscillation frequency, dynamic stiffness, and Quebec Baclain Disability Scale scores of the two groups were significantly lower than before treatment (P < 0.05), while the experimental group was better than the control group (P < 0.05). Four weeks after treatment, the Quebec baclain disability scale scores of two groups were improved compared with those after the completion of all treatments (P < 0.05), and the Quebec baclain disability scale score in the control group was significantly improved compared with that in the experimental group (P < 0.05). The number of effective and total effective cases in the experimental group were both better than those in the control group (P < 0.05) after the completion of all treatments. The overall efficiency of the experimental group (97%) was higher than that of the control group (80%; P < 0.05). Four weeks after treatment, the number of effective and total effective cases in the experimental group were also better than those in the control group (P < 0.01). The overall efficiency of the control group (63%) was significantly decreased (P < 0.05). Although the overall efficiency of the experimental group (93%) decreased (P < 0.05), the clinical efficacy was mainly maintained. To conclude, deep muscle stimulation with routine physical therapies can effectively relieve pain, reduce muscle tone and stiffness of erector spinaes, and improve and keep the clinical efficacy in patients with chronic non-specific low back pain. [ABSTRACT FROM AUTHOR]

Microgravity induces spinal elongation and Low Back Pain (LBP) but the pathophysiology is unknown. Changes in paraspinal muscle viscoelastic properties may play a role. Dry Immersion (DI) is a ground-based microgravity analogue that induces changes in m. erector spinae superficial myofascial tissue tone within 2 h. This study sought to determine whether bilateral m. erector spinae tone, creep, and stiffness persist beyond 2 h; and if such changes correlate with DI-induced spinal elongation and/or LBP. Ten healthy males lay in the DI bath at the Institute of Biomedical Problems (Moscow, Russia) for 6 h. Bilateral lumbar (L1, L4) and thoracic (T11, T9) trunk myofascial tone, stiffness and creep (MyotonPRO), and subjective LBP (0- 10 NRS) were recorded before DI, after 1h, 6 h of DI, and 30min post. The non-standing spinal length was evaluated on the bath lifting platform using a bespoke stadiometer before and following DI. DI significantly modulated m. erector spinae viscoelastic properties at L4, L1, T11, and T9 with no effect of laterality. Bilateral tissue tone was significantly reduced after 1 and 6 h DI at L4, L1, T11, and T9 to a similar extent. Stiffness was also reduced by DI at 1 h but partially recovered at 6 h for L4, L1, and T11. Creep was increased by DI at 1 h, with partial recovery at 6 h, although only T11 was significant. All properties returned to baseline 30 min following DI. Significant spinal elongation (1.17 ± 0.20 cm) with mild (at 1 h) to moderate (at 6 h) LBP was induced, mainly in the upper lumbar and lower thoracic regions. Spinal length increases positively correlated (Rho = 0.847, p = 0.024) with middle thoracic (T9) tone reduction, but with no other stiffness or creep changes. Spinal length positively correlated (Rho = 0.557, p = 0.039) with Max LBP; LBP failed to correlate with any m. erector spinae measured parameters. The DI-induced bilateral m. erector spinae tone, creep, and stiffness changes persist beyond 2 h. Evidence of spinal elongation and LBP allows suggesting that the trunk myofascial tissue changes could play a role in LBP pathogenesis observed in real and simulated microgravity. Further study is warranted with longer duration DI, assessment of IVD geometry, and vertebral column stability. [ABSTRACT FROM AUTHOR]

Microgravity induces spinal elongation and Low Back Pain (LBP) but the pathophysiology is unknown. Changes in paraspinal muscle viscoelastic properties may play a role. Dry Immersion (DI) is a ground-based microgravity analogue that induces changes in m. erector spinae superficial myofascial tissue tone within 2 h. This study sought to determine whether bilateral m. erector spinae tone, creep, and stiffness persist beyond 2 h; and if such changes correlate with DI-induced spinal elongation and/or LBP.Ten healthy males lay in the DI bath at the Institute of Biomedical Problems (Moscow, Russia) for 6 h. Bilateral lumbar (L1, L4) and thoracic (T11, T9) trunk myofascial tone, stiffness and creep (MyotonPRO), and subjective LBP (0-10 NRS) were recorded before DI, after 1h, 6 h of DI, and 30min post. The non-standing spinal length was evaluated on the bath lifting platform using a bespoke stadiometer before and following DI.DI significantly modulated m. erector spinae viscoelastic properties at L4, L1, T11, and T9 with no effect of laterality. Bilateral tissue tone was significantly reduced after 1 and 6 h DI at L4, L1, T11, and T9 to a similar extent. Stiffness was also reduced by DI at 1 h but partially recovered at 6 h for L4, L1, and T11. Creep was increased by DI at 1 h, with partial recovery at 6 h, although only T11 was significant. All properties returned to baseline 30 min following DI. Significant spinal elongation (1.17 ± 0.20 cm) with mild (at 1 h) to moderate (at 6 h) LBP was induced, mainly in the upper lumbar and lower thoracic regions. Spinal length increases positively correlated (Rho = 0.847, p = 0.024) with middle thoracic (T9) tone reduction, but with no other stiffness or creep changes. Spinal length positively correlated (Rho = 0.557, p = 0.039) with Max LBP; LBP failed to correlate with any m. erector spinae measured parameters.The DI-induced bilateral m. erector spinae tone, creep, and stiffness changes persist beyond 2 h. Evidence of spinal elongation and LBP allows suggesting that the trunk myofascial tissue changes could play a role in LBP pathogenesis observed in real and simulated microgravity. Further study is warranted with longer duration DI, assessment of IVD geometry, and vertebral column stability.

A decrease in muscle tone induced by space flight requires a standardized assessment of changes to control the state of the neuromuscular system. This study is a step toward the development of a unified protocol, aimed at determining the initial effect of the presence or withdrawal of support on muscle tone, the effects of a 2-h supportlessness in Dry Immersion (DI) experiments, and the changes in muscle tone depending on the site of measurement. To perform measurements of changes in muscle tone, we used a MyotonPRO device. The list of muscles that we assessed includes: trunk – mm. deltoideus posterior, trapezius, erector spinae; leg – mm. biceps femoris, rectus femoris, tibialis anterior, soleus, gastrocnemius; foot – m. flexor digitorum brevis, tendo Achillis, aponeurosis plantaris. The study involved 12 healthy volunteers (6 men, 6 women) without musculoskeletal disorders and aged 32.8 ± 1.6 years. At the start of DI, there was a significant decrease in muscle tone of the following muscles: mm. tibialis anterior (−10.9%), soleus (−9.6%), erector spinae (−14.4%), and the tendo Achillis (−15.3%). The decrease continued to intensify over the next 2 h. In contrast, the gastrocnemius muscle demonstrated an increase in muscle tone (+7.5%) 2 h after the start of DI compared to the immediate in-bath baseline. Muscle tone values were found to be site-dependent and varied in different projections of mm. erector spinae and soleus. In previous experiments, we observed a high sensitivity of the myotonometry technique, which was confirmed in this study. To make it possible to compare data from different studies, a standardized protocol for measuring muscle tone for general use in gravitational physiology needs to be developed.

A decrease in muscle tone induced by space flight requires a standardized assessment of changes to control the state of the neuromuscular system. This study is a step toward the development of a unified protocol, aimed at determining the initial effect of the presence or withdrawal of support on muscle tone, the effects of a 2-h supportlessness in Dry Immersion (DI) experiments, and the changes in muscle tone depending on the site of measurement. To perform measurements of changes in muscle tone, we used a MyotonPRO device. The list of muscles that we assessed includes: trunk – mm. deltoideus posterior, trapezius, erector spinae; leg – mm. biceps femoris, rectus femoris, tibialis anterior, soleus, gastrocnemius; foot – m. flexor digitorum brevis, tendo Achillis, aponeurosis plantaris. The study involved 12 healthy volunteers (6 men, 6 women) without musculoskeletal disorders and aged 32.8 ± 1.6 years. At the start of DI, there was a significant decrease in muscle tone of the following muscles: mm. tibialis anterior (−10.9%), soleus (−9.6%), erector spinae (−14.4%), and the tendo Achillis (−15.3%). The decrease continued to intensify over the next 2 h. In contrast, the gastrocnemius muscle demonstrated an increase in muscle tone (+7.5%) 2 h after the start of DI compared to the immediate in-bath baseline. Muscle tone values were found to be site-dependent and varied in different projections of mm. erector spinae and soleus. In previous experiments, we observed a high sensitivity of the myotonometry technique, which was confirmed in this study. To make it possible to compare data from different studies, a standardized protocol for measuring muscle tone for general use in gravitational physiology needs to be developed. [ABSTRACT FROM AUTHOR]

Objective:To examine the inter-rater reliability of MyotonPRO under B-ultrasound guidance in assessment of stroke patients'muscle tone.Methods:A total of 28 stroke patients were assessed their muscle mechanical properties of biceps brachii and flexor carpi radialis muscles in relaxed state with MyotonPRO under the B-ultrasound guidance by two testers within 24 hours. Inter-rater reliability of muscle properties was determined using intraclass correlation coefficient (ICC), the standard error of measurement (SEM), the minimal detectable change (MDC90) and Bland-Altman analysis were performed by SPSS.Results:The ICC was above 0.9 in the ten-time scan pattern. The SEM and MDC90of biceps brachii and flexor carpi radialis muscles indicated small measurement error (SEM%90%

Background and purpose: The MyotonPRO is a portable device that measures muscle tone and biomechanical muscle properties objectively. MyotonPRO has already proven to be effective in measuring muscle properties in healthy and diseased populations. However, to the best of our knowledge, it has never been tested in individuals suffering from paratonia, a form of hypertonia frequently accompanying dementia. The aims of the present study were to (1) compare muscle tone, elasticity, and stiffness between 3 different subpopulations of young and old healthy adults and individuals with paratonia, and (2) investigate the intra- and interrater reproducibility of MyotonPRO measurements of the biceps brachii (BB) muscle in each subpopulation. Methods: MyotonPRO measurements of muscle tone, elasticity, and dynamic stiffness were carried out by 2 investigators on 2 different days over the BB muscles of 54 participants (18 healthy young adults, 20 healthy older adults, and 16 older individuals with paratonia). Muscle properties were compared between subpopulations using ANOVA/Welch and post hoc tests. Reliability (intraclass correlation coefficient) and agreement parameters (standard error of measurement and the minimal detectable change) were calculated. Results: Statistically significant differences between subpopulations were found in all parameters, except for stiffness between healthy elderly and individuals with paratonia. In the healthy subpopulations, (a) intrarater reliability was very high and intrarater agreement was good between 2 consecutive series, (b) between days intrarater reliability was low to high and intrarater agreement was variable, (c) interrater reliability was high to very high and interrater agreement was good. In individuals with paratonia, (a) intrarater reliability was moderate to high and agreement was variable between series, (b) between days intrarater reliability was poor to moderate and agreement was poor, (c) interrater reliability ranged from low to high with poor agreement. Conclusions: MyotonPRO measurements of the BB muscle showed good reproducibility in both healthy subpopulations, particularly for measurements performed within the same day. In individuals with paratonia, reliability and agreement were substantially lower. MyotonPRO can be used in clinical assessment and research. However, in individuals with paratonia, careful interpretation of results is required. Research in a larger sample of persons with paratonia at different stages of disease severity is recommended. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to analyze the effects of aging on the viscoelastic properties of the upper trapezius (UT) and the sternocleidomastoid (SCM) muscle during transition from lying to sitting position. Materials and methods The study included 39 older (mean age 67 ± 5.9 years) and 36 younger (21.1 ± 1.8 years) women. Tone, stiffness and elasticity of the UT and the SCM were measured by means of myotonometry (MyotonPRO) in lying and then, in sitting position. The results were compared using two-way analysis of variance. Results Irrespective of the position, older women presented with significantly higher muscle tone, stiffness and elasticity than younger subjects (P < 0.05). In both groups, the transition from lying to sitting position resulted in a decrease (P < 0.05) in the tone and stiffness, but not the elasticity (P > 0.05) of the SCM, and stimulated an increase in the tone, stiffness and elasticity of the UT (P < 0.05). The degree of changes in both study groups was similar, except from the absolute value of the UT elasticity, significantly higher increase in older women than in younger subjects (P < 0.05). Conclusion Age contributes to an increase in the stiffness and tone of the UT and the SCM, as well as to a decrease in the elasticity of these muscles in female subjects. In contrast, age exerts only a slight effect on the mechanical properties of both muscles during transition from lying to sitting position. [ABSTRACT FROM AUTHOR]

Introduction/Background Treatment related shoulder dysfunction and anterior chest wall stiffness is common in breast cancer patients. Radiotherapy is known to alter the properties of muscles such as fibrosis, but it is difficult to objectively assess. Objective measurements of muscle properties can be useful for evaluating these problems and the effect of intervention. Our study aimed to assess changes in serial muscle properties associated with radiotherapy in breast cancer patients using MyotonPRO, device measuring muscle properties. Material and method Thirty-five breast cancer patients who underwent mastectomy and scheduled to undergo radiotherapy were enrolled. Frequency (tone, Hz) and stiffness (N/m) were measured in both pectoralis major (PM), sternocleidomastoid (SMC) and upper trapezius (UT) before radiotherapy and immediately after radiotherapy. Paired t -test was used to investigate the side-to-side difference and changes associated with radiotherapy of tone and stiffness of muscles around shoulder. Results Before radiotherapy, the stiffness and tone of affected PM were significantly higher than unaffected PM. Immediately after radiotherapy, the stiffness and tone of affected PM were still significantly higher than unaffected PM and the difference became larger than before radiotherapy. Although there was no side-to-side difference of parameters before radiotherapy, the stiffness of affected UT was significantly higher than unaffected UT immediately after radiotherapy. Stiffness/tone of affected PM and affected UT increased significantly immediately after radiotherapy compared to before radiotherapy. Conclusion After operation, only the tone and stiffness of affected PM were increased. After radiotherapy, the stiffness and tone of affected PM were higher than before radiotherapy, and the tone and stiffness of affected UT were also increased. Our findings confirmed that surgical treatment and radiotherapy affect the stiffness and tone of affected PM. And stiffness and tone of affected UT increased before and after radiotherapy, which is thought to be due to posture of receiving radiotherapy. [ABSTRACT FROM AUTHOR]