Mechanical Relaxation Time Research Articles

The role of muscle function and pointe shoe characteristics in Arabesque movement among ballet dancers with non-specific low back pain

ABSTRACT This study aimed to investigate posterior chain muscle function and the influence of pointe shoes in ballet dancers with and without low back pain (LBP) in the Arabesque. Twenty-nine young professional ballet dancers (17 with LBP and 12 healthy controls) were recruited. Muscle strength and mechanical properties of the erector spinae and hamstrings were assessed. The displacement of centre of mass (COM) during Arabesque under different shoe conditions (R-class, Chacott, and own shoes) was measured with a motion capture system. The LBP group exhibited greater dynamic stiffness and decreased mechanical stress relaxation time in the lateral hamstring compared to the control group. During Arabesque, the LBP group demonstrated significantly greater anterior-posterior displacement of the COM and a larger percentage of time to achieve maximal trunk extension angle. The COM displacement in vertical and medial-lateral directions was smaller in the R-class than in their own shoes. LBP impacts muscle mechanical properties, particularly in the lateral hamstring. The compromised muscle function resulted in a longer time to spinal extension during Arabesque, signifying that reduced trunk control contributed to greater COM displacement. Hence, it is essential to emphasise that evaluating muscle properties and dynamic postural control is imperative for dancers experiencing LBP.

The photothermal interaction of a viscothermoelastic semiconducting ceramic solid sphere under the Green–Naghdi heat conduction model

This work introduces a new mathematical model for viscothermoelastic semiconducting solid spheres of ceramic materials considering the photothermal interaction using three types of the Green–Naghdi heat conduction model. The outer surface of a solid sphere is loaded thermally using ramp-type heat as a boundary condition. Following that, Laplace transforms and their inversion forms have been applied. The figures show that the mechanical relaxation time and ramp-time heat parameters have significant effects on the increase in carrier density and temperature, in addition to strain, displacement, the average of principal stresses, and the strain-energy density. The energy produced by viscothermoelastic semiconducting materials based on photothermal interaction may be controlled by the ramp-time heat parameter. The novelty of this work is to test the three types of the Green–Naghdi heat conduction model and apply the model to zirconia, a ceramic material.

Determinants of viscoelasticity and flow activation energy in biomolecular condensates.

The form and function of biomolecular condensates are intimately linked to their material properties. Here, we integrate microrheology with molecular simulations to dissect the physical determinants of condensate fluid phase dynamics. By quantifying the timescales and energetics of network relaxation in a series of heterotypic viscoelastic condensates, we uncover distinctive roles of sticker motifs, binding energy, and chain length in dictating condensate dynamical properties. We find that the mechanical relaxation times of condensate-spanning networks are determined by both intermolecular interactions and chain length. We demonstrate, however, that the energy barrier for network reconfiguration, termed flow activation energy, is independent of chain length and only varies with the strengths of intermolecular interactions. Biomolecular diffusion in the dense phase depends on a complex interplay between viscoelasticity and flow activation energy. Our results illuminate distinctive roles of chain length and sequence-specific multivalent interactions underlying the complex material and transport properties of biomolecular condensates.

Controlling spatiotemporal mechanics of globular protein-polymer hydrogel via metal-coordination interactions

Mechanical properties of hydrogels are dependent on their spatial and temporal structural properties. Several attempts have been made to tune the mechanical properties of hydrogels either through controlling spatial or temporal design elements. However, controlling both elements simultaneously still proves to be extremely difficult and elusive. This goal could be achieved by combining the function and structure of globular proteins with the versatility of synthetic polymers to form a hybrid hydrogel. In this study, a physically crosslinked protein-polymer hydrogel (PPH) was synthesized. As a model globular protein, bovine serum albumin (BSA) was used together with poly(methacrylamide) to control hydrogel spatiotemporal mechanics. In order to control the temporal hierarchy (crosslinking kinetics) we used the coordination sites of BSA to create metal-coordination crosslinks, while the folding-unfolding of BSA triggered by specific metal ions was exploited to define the network architecture (spatial hierarchy). Mechanical properties, relaxation times, and microstructure were found to be affected by the nature of metal ions in the PPHs. It is anticipated that understanding of spatiotemporal mechanics will facilitate the development of novel PPHs with fine-tuned mechanical properties.

Relationship between cardiac mechanical properties and cardiac magnetic resonance imaging at rest in childhood acute lymphoblastic leukemia survivors.

The characterization of cardiac mechanical properties may contribute to better understanding of doxorubicin-induced cardiotoxicity. Our study aims to investigate the relationship between cardiac mechanical properties, T1 and T2 relaxation times and partition coefficient.Fifty childhood acute lymphoblastic leukemia survivors underwent a cardiac magnetic resonance (CMR) at rest on a 3T MRI system and included a standard ECG-gated 3(3)3(3)5 MOLLI sequence for T1 mapping and an ECG-gated T2-prepared TrueFISP sequence for T2 mapping. Partition coefficient, ejection fraction, end-diastolic volume (EDV) and end-systolic volume (ESV) were calculated. CircAdapt model was used to study cardiac mechanical performance (left ventricle stiffness (LVS), contractility (LVC) and pressure (Pmin and Pmax), cardiac work efficiency (CWE) and ventricular arterial coupling).In the whole cohort, our results showed that LVC (R2 = 69.2%, r = 0.83), Pmin (R2 = 62.9%, r = 0.79) and Pmax can be predicted by significant CMR parameters, while T1 (R2 = 23.2%, r = 0.48) and partition coefficient (R2 = 13.8%, r = 0.37) can be predicted by significant cardiac mechanical properties. In SR group LVS (R2 = 94.8%, r = 0.97), LVC (R2 = 93.7%, r = 0.96) and Pmin (R2 = 90.6%, r = 0.95) can be predicted by significant cardiac mechanical properties, while in HR + DEX group CWE (R2 = 49.8%, r = 0.70) can be predicted by significant cardiac mechanical properties. Partition coefficient (R2 = 72.6%, r = 0.85) can be predicted by significant CMR parameters in SR group.Early characterization of cardiac mechanical properties from CMR parameters has the potential to early detect doxorubicin-induced cardiotoxicity.

The influence of the mechanical damage on a viscothermoelastic nanobeam due to ramp-type heating under Green-Naghdi theory type-II

The main object of this work is to analyze viscothermoelastic homogeneous and isotropic nanobeams under the effect of mechanical damage. A Green-Naghdi type-II model of thermoelasticity has been constructed under simply supported conditions. Moreover, the Laplace transforms have been applied for the governing differential equations. Tzou iteration method with approximation has been applied to calculate the Laplace inverse transforms. The numerical results are presented and validated for use in a viscothermoelastic rectangular nanobeam of silicon nitride when it has been thermally loaded by ramp-type heating and simple support. The numerical results have been demonstrated in different figures to stand on the effects of the mechanical damage variable, mechanical relaxation times parameters, and ramp-time heat parameter on all the studied functions. We conclude that the effect of the mechanical damage variable, ramp-time heating parameter, and mechanical relaxation times parameters are highly influential on all the studied functions and thermomechanical waves.

Magnetic Resonance Acoustic Radiation Force Imaging (MR-ARFI) for the monitoring of High Intensity Focused Ultrasound (HIFU) ablation in anisotropic tissue.

We introduce a non-invasive MR-Acoustic Radiation Force Imaging (ARFI)-based elastography method that provides both the local shear modulus and temperature maps for the monitoring of High Intensity Focused Ultrasound (HIFU) therapy. To take tissue anisotropy into account, the local shear modulus μ is determined in selected radial directions around the focal spot by fitting the phase profiles to a linear viscoelastic model, including tissue-specific mechanical relaxation time τ. MR-ARFI was evaluated on a calibrated phantom, then applied to the monitoring of HIFU in a gel phantom, ex vivo and in vivo porcine muscle tissue, in parallel with MR-thermometry. As expected, the shear modulus polar maps reflected the isotropy of phantoms and the anisotropy of muscle. In the HIFU monitoring experiments, both the shear modulus polar map and the thermometry map were updated with every pair of MR-ARFI phase images acquired with opposite MR-ARFI-encoding. The shear modulus was found to decrease (phantom and ex vivo) or increase (in vivo) during heating, before remaining steady during the cooling phase. The mechanical relaxation time, estimated pre- and post-HIFU, was found to vary in muscle tissue. MR-ARFI allowed for monitoring of viscoelasticity changes around the HIFU focal spot even in anisotropic muscle tissue.

Control of ultrafast laser ablation efficiency by stress confinement due to strong electron localization in high-entropy alloys

In the context of current state of the art, understanding the laser ablation efficiency decrease for pulse durations exceeding the mechanical relaxation time of a few ps remains a pending research question. A heuristic approach may be used to reveal the role of effective penetration depth on ablation efficiency. Extending familiar contributions of this quantity by a term related to the mechanical surface expansion during pulse irradiation, the relation of ablation efficiency and pulse duration is deciphered. Thus, longer pulses are coupled into an expanded surface, revealing a direct link to the violation of stress confinement. To best demonstrate this hypothesis, a material with high electron–phonon coupling as well as low thermal conductivity, i.e., strong electron localization, is required. These properties are accomplished by high-entropy alloys, and the CrMnFeCoNi alloy serves as prime candidate. We report on single-pulse ablation efficiency experiments of the CrMnFeCoNi alloy which are support by our proposed model.

Age and sex differences in the biomechanical and viscoelastic properties of upper limb muscles in middle-aged and older adults: A pilot study

Whether muscle properties gradually change with age and how muscle properties are affected by sex remain unclear. In this study, we investigated the influence of age and sex on the biomechanical and viscoelastic properties of arm muscles in middle-aged and older adults. In this cross-sectional study, 80 healthy participants were divided by sex (male and female), and each sex group, by 10-year age ranges (40–49, 50–59, 60–69, and 70–79 years). Muscle properties, including tone, stiffness, elasticity, and mechanical stress relaxation time, were measured with the MyotonPRO. Our results showed that the muscle tone and elasticity of the deltoid and flexor carpi radialis, and the muscle tone of the flexor carpi ulnaris, were significantly greater in men than in women, whereas the stress relaxation time of the triceps was significantly greater in women than in men. Significantly greater muscle stiffness in the biceps brachii was found in the participants over 50 years old. Less muscle elasticity was found in the deltoid, triceps, and flexor carpi ulnaris in those over 70 years old. In conclusion, age and sex have considerable impacts on upper-limb muscle properties in middle-aged and older adults, which should be taken into consideration when planning health promotion projects.

PSXII-10 Non-invasive measurements of woody and normal condition in broiler breast meat

Abstract Woody Breast (WB) defines a quality issue resulting from a muscle abnormality in chicken meat, which makes the breast meat more rigid and sometimes pale in color with inferior texture. The frequency of this defect in Europe is over 30% and some have argued that similar levels may exist in the United States. Given that chicken with WB are of poor economic value and are discriminated by the consumers, producers face significant economic hardship under the current production paradigm. One of the problems in identifying the biological mechanism responsible for WB is that the occurrence and severity of WB can be only identified after harvest. This study is to investigate the physical characteristics of WB and normal breast (NB) in live chicken using a non-invasive, digital palpation device named as “MyotonPRO®”. This technology provides the measurements of superficial muscles regarding dynamic stiffness (100–1500 N/m; DS), elasticity (0.3–2.5), mechanical stress relaxation time (5–40 ms; MSRT) and ratio of deformation and relaxation time (0.3–2.5; RDRT). One hundred breast meat samples were used in this analysis (WB: 50; NB: 50), which were obtained from a local processing plant one day after harvest and sorted based on WB scoring with the naked eye (0, 1 for NB; 2, 3 for WB). One way ANOVA was used to analyze the data as a statistical model. The least squares means of the following variables were significantly different between WB and NB (P < 0.01): DS (603.4 vs 565.8; N/m), and elasticity (1.40 vs 1.55). However, MSRT and RDRT were not significantly different (P > 0.05). These results collectively show that the non-invasive measurements of WB differ from NB. The degree of muscle hardness in WB can be considered as a trait to be selected, and utilized for the genetic/genomic selection program collecting the measurements before harvest.

Quantifying the Changes of Mechanical and Electrical Properties of Paralyzed Muscle in Survivors With Cervical Spinal Cord Injury.

Background: Survivors with spinal cord injury (SCI) have neuromuscular deficits such as muscle atrophy that lead to functional impairments. This study utilized myotonometry and electrical impedance myography (EIM) to quantitatively evaluate the changes in muscle mechanical properties and compositions after SCI.Methods: This study adopted a cross-sectional design. Eighteen SCI patients and 18 healthy individuals were recruited. The outcome measures were: (1) The myotonometer measured muscle mechanical parameters of oscillation frequency (freq), dynamic stiffness, logarithmic decrement (decr), mechanical stress relaxation time, and indication of creep. (2) The electrical impedance myography measured parameters of resistance (R), reactance (X), and phase angle (θ). (3) muscle strength (maxForce); (4) clinical scales of Manual Muscle Testing (MMT) and modified Ashworth scale (MAS). All outcome measures were compared between the bicep brachii muscle of the weaker side of the SCI group and the non-dominate side of the healthy group. Correlation analysis was performed at quantitative data and clinical scales.Results: Freq, stiffness, and maxForce of the SCI group were significantly lower (p < 0.01) than those of the healthy control. The relaxation time and creep were significantly higher in the SCI group than in the control group. Significant differences of R and Xc were observed between the two groups. Significant correlation was observed between freq, stiffness, and months past injury, and between Xc, creep, and relaxation time.Conclusions: Reduced muscle tone and stiffness might relate to muscle atrophy, and higher relax time and creep may be caused by poor contractile ability. The changes in EIM parameters could indirectly reflect the muscle cell size, and fatty and connective tissue alterations. These findings support the feasibility of myotonometer and EIM to quantify muscle mechanical and intrinsic properties in patients with SCI. The results could facilitate the understanding of neuromuscular changes that are related to functional impairments.

Regional Differences of Mechanical Properties in a Biceps Brachii Following Eccentric Exercise

PURPOSE: This study aimed to examine the effects of eccentric exercise (ECC) on the indices of mechanical properties together with markers of exercise-induced muscle damage (EIMD) in different sites of the biceps brachii (BB) muscle.METHODS: ECC using an elbow joint was performed in 13 non-trained, college men. Global symptoms of EIMD were identified through changes in muscle soreness and serum creatine kinase (CK) activity, including muscle function following ECC. To evaluate regional EIMD, muscle swelling and tenderness as well as muscular echo intensity were measured at distal (4 cm above the elbow joint) and middle (30% of the distance from the antecubital crease to the acromion) sites within the BB muscle. A handheld myotonometer was used to estimate changes in mechanical properties, that is, oscillation frequency (F), dynamic stiffness (S), and relaxation time (R), of BB muscles after ECC.RESULTS: A significant difference in the major markers of EIMD, such as muscle soreness and serum CK activity, along with parameters of muscle function, was observed after ECC compared to baseline. Although all indirect markers of regional muscle damage demonstrated meaningful differences between before and after ECC, no statistically significant interaction between the distal and middle sites was observed in any of the markers. After ECC, both distal and middle sites showed significant changes in F, S, and R, but no statistical differences in changes in muscle mechanical properties were observed between localized muscle sites within BB muscles.CONCLUSIONS: Changes in mechanical properties, including regional muscle damage, seem to be uniformly influenced by different anatomical locations within the BB muscle, such as elbow flexors, following ECC.

Skin anisotropy: Finding the optimal incision line for volar forearm in males and females

PurposeProper understanding of skin biomechanics, viscoelasticity and investigation of skin tension vectors is necessary to find optimal incision lines. Great tension across a healing wound after any surgical procedure might lead to forming hypertrophic scars. The aim of the study was to investigate tension lines in volar forearm skin in young males and females, in order to ensure best incision line. MethodsFive biomechanical and viscoelastic parameters were measured using a hand-held myotonometer: Oscillation Frequency [Hz], Dynamic Stiffness [N/m], Logarithmic Decrement of tissue's natural oscillation, Mechanical Stress Relaxation Time [ms], and Creep. Measurements were taken in four different directions; Along Forearm, Across Forearm, Along Langer's Line and Across Langer's Line. ResultsSignificant main effects for direction were found for Oscillation Frequency (p < 0.001, η2 = 0.371) [Hz], Dynamic Stiffness (p < 0.001, η2 = 0.522) [N/m], Logarithmic Decrement (p < 0.001, η2 = 0.083), Mechanical Stress Relaxation Time (p < 0.001, η2 = 0.494) [ms] and Creep (p < 0.001, η2 = 0.480). For each parameter except for logarithmic decrement results obtained Along Langers Line and Across Forearm were significantly different to Across Langers Line and Along Forearm (p < 0.001, d = −2.76 – 2.66). Significant main effects for sex were found for logarithmic decrement Along Forearm (p < 0.001, d = 1.698) and Across Langer's Line (p = 0.021, d = 1.697). ConclusionsOur results suggested that optimal incision line for this age group in males and females could potentially be performed diagonally i.e. Across Langer's Line or parallel i.e. Along Forearm to forearm axis. These directions would provide the lowest tension across a healing wound and possibly minimalize the risk of hypertrophic scarring post incision.

The dynamic viscoelastic characterisation and magnetic resonance imaging of poly(vinyl alcohol) cryogel: Identifying new attributes and opportunities

Poly(vinyl alcohol) (PVA) cryogel is a biocompatible, synthetic hydrogel, compatible with magnetic resonance (MR) imaging. It is widely used as a biomaterial in tissue scaffolds and mimics to test various diagnostic techniques. The aim of this study is to characterise the effect of varying PVA concentration, molecular weight (MW) and manufacturing protocol on the viscoelastic mechanical properties and MR T2 relaxation time. Further to this MR imaging (MRI) was investigated as a method to quantify material homogeneity. Cylindrical samples of PVA, of varying MW, concentration and number of freeze thaw cycles (FTCs), were manufactured. Dynamic mechanical analysis was performed to evaluate the storage and loss moduli between frequencies of 0.5 and 10 Hz. MR T2 relaxation maps were imaged using a 7 T MRI instrument. Storage and loss moduli were shown to increase with MW, concentration, or the number of FTCs; with storage modulus ranging from 55 kPa to 912 kPa and loss modulus ranging from 6 kPa to 103 kPa. MR T2 relaxation time was shown to increase linearly with PVA concentration. The qualitative and quantitative heterogeneity of the PVA sample were identified through MR T2 relaxation time maps. Excitingly, PVA demonstrated a composition-dependent casual correlation between the viscoelastic mechanical properties and MR T2 relaxation time. In conclusion, this research thoroughly characterised the viscoelastic mechanical properties of PVA to support its extensive use as a biomaterial, and demonstrated the use of MRI to non-invasively identify sample heterogeneity and to predict the composition-dependent viscoelastic properties of PVA.

Shock Structure and Relaxation in the Multi-Component Mixture of Euler Fluids

The shock structure problem is studied for a multi-component mixture of Euler fluids described by the hyperbolic system of balance laws. The model is developed in the framework of extended thermodynamics. Thanks to the equivalence with the kinetic theory approach, phenomenological coefficients are computed from the linearized weak form of the collision operator. Shock structure is analyzed for a three-component mixture of polyatomic gases, and for various combinations of parameters of the model (Mach number, equilibrium concentrations and molecular mass ratios). The analysis revealed that three-component mixtures possess distinguishing features different from the binary ones, and that certain behavior may be attributed to polyatomic structure of the constituents. The multi-temperature model is compared with a single-temperature one, and the difference between the mean temperatures of the mixture are computed. Mechanical and thermal relaxation times are computed along the shock profiles, and revealed that the thermal ones are smaller in the case discussed in this study.

Highly Spherical Nanoparticles Probe Gigahertz Viscoelastic Flows of Simple Liquids Without the No-Slip Condition.

Simple liquids are conventionally described by Newtonian fluid mechanics, based on the assumption that relaxation processes in the flow occur much faster than the rate at which the fluid is driven. Nanoscale solids, however, have characteristic mechanical response times on the picosecond scale, which are comparable to mechanical relaxation times in simple liquids; as a result, viscoelastic effects in the liquid must be considered. These effects have been observed using time-resolved optical measurements of vibrating nanoparticles, but interpretation has often been complicated by finite velocity slip at the liquid-solid interface. Here, we use highly spherical gold nanoparticles to drive flows that are theoretically modeled without the use of the no-slip boundary condition at the particle surface. We obtain excellent agreement with this analytical theory that considers both the compression and shear relaxation properties of the liquid.

Nanoparticle-Fluid Interactions at Ultrahigh Acoustic Vibration Frequencies Studied by Femtosecond Time-Resolved Microscopy.

Liquid viscous and viscoelastic properties are very important parameters in determining rheological phenomena. Mechanical resonators with extremely high vibrational frequencies interacting with simple liquids present a wide range of applications from mass sensing to biomechanics. However, a lack of understanding of fluid viscoelasticity greatly hinders the utilization of mechanical resonators. In this paper, the high frequency acoustic vibrations of Au nanoplates with large quality factors were used to probe fluid properties (water, glycerol, and their mixtures) through time-resolved pump-probe microscopy experiments. For water, viscous damping was clearly observed, where an inviscid effect was only detected previously. Adding glycerol to the water increases the fluid viscosity and leads to a bulk viscoelastic response in the system. The experimental results are in excellent agreement with a continuum mechanics model for the damping of nanoplate breathing modes in liquids, confirming the experimental observation of viscoelastic effects. In addition to the breathing modes of the nanoplates, Brillouin oscillations are observed in the experiments. Analysis of the frequency of the Brillouin oscillations also shows the presence of viscoelastic effects in the high-viscosity solvents. The detection and analysis of viscous damping in liquids is important not only for understanding the energy dissipation mechanisms and providing the mechanical relaxation times of the liquids but also for developing applications of nanomechanical resonators for fluid environments.

Influence of stress confinement, particle shielding and re-deposition on the ultrashort pulse laser ablation of metals revealed by ultrafast time-resolved experiments

The ablation rate in double-pulse material processing is strongly influenced by the pulse separation. For pulse separations exceeding 3 ps a significant decrease in ablation volume has been observed. This was attributed to three mechanisms: rarefaction wave interaction, shielding by ablation plume and material re-deposition. Here we present carefully designed double-pulse ablation experiments on three industrially relevant metals: stainless steel, aluminum and copper and interpret them based on ablation dynamics derived from ultrafast time-resolved pump-probe microscopy and ellipsometry. Adjustment of the fluence distribution within the double-pulse allows us to separate effects arising from rarefaction wave suppression and shielding/re-deposition. We found that the rarefaction wave contribution to the double-pulse ablation volume is about 25% for aluminum and stainless steel and about 40% for copper. A pronounced re-deposition was observed for stainless steel and aluminum, while for copper shielding by the ablation plume plays a dominant role. It was revealed that the ablation volume stays maximal, if the pulse energy is deposited within the mechanical relaxation time of (2–5)ps. According to our findings the ablation process exerts maximum efficiency and precision, when energy is coupled into the material before mechanical relaxation or after material surface equilibration.

Characterization of the photothermal interaction on a viscothermoelastic semiconducting solid cylinder due to rotation under Lord-Shulman model

This paper deals with the photothermal interaction of an isotropic, homogenous, semiconducting, viscothermoelastic solid cylinder in the context of Lord-Shulman's of generalized thermoelasticity theory. The cylinder rotates around its axis with constant angular velocity. The bounding surface of the cylinder has been thermally shocked. The governing equations have been constructed in the Laplace transform domain and numerically calculated inversions of Laplace using the Tzou method. The numerical results for the carrier density increment, temperatures increment, strain, stress, and stress-strain energy have been represented graphically with various values mechanical relaxation time, angular velocity parameter, and lifetime parameter of a photogenerated carrier. The mechanical relaxation time and angular velocity of the rotation parameter have minimal effects on the carrier density function and temperature increment, while its effects on the strain, stress, and stress-strain energy are significant. The photogenerated carrier's lifespan parameter has essential implications on all functions studied.

Biomechanical and viscoelastic properties of the ankle muscles in men with previous history of ankle sprain

In this study, we aimed to explore the impact of previous history of lateral ankle sprain on the mechanical and viscoelastic properties of the tibialis anterior (TA), peroneus longus (PL) and gastrocnemius lateralis (GL) and medialis (GM) in asymptomatic men. For this purpose, a group of 26 men with previous history of lateral ankle sprain (ASG) and a control group (CG) of 29 healthy counter-parts participated in this study. Tone, stiffness, elasticity and mechanical stress relaxation time were measured using a myotonometer in a single session. Higher tone was noted for TA and GL in ASG as compared to CG (effect size of Cohen’s d = 0.57 [p = 0.04] and 0.59 [p = 0.04], respectively). Further, stiffness was higher in ASG than in CG for TA (d = 0.56; p = 0.04), PL (d = 0.58; p = 0.04) and GL (d = 0.63; p = 0.02). Stress relaxation time was also lower for the ASG compared to the CG for TA (d = 0.61; p = 0.03), PL (d = 0.55; p = 0.04) and GL (d = 0.68; p = 0.02). There were no significant differences between groups in elasticity (p > 0.05). GM experienced no significant changes after ankle sprain in any of the variables (p > 0.05). To conclude, previous history of lateral ankle sprain results in higher TA and GL muscle tone. Likewise, these muscles in addition to PL exhibit less deformation against resistance due to their increased stiffness, thus needing a shorter time to restore to their original shape after deformation.