A Mechanical Model Representation of the In Vivo Behaviour of Bulk Tissue

Volume 2 ◽  
2004 ◽  
Author(s):  
Serdar Aritan ◽  
S. Olutunde Oyadiji ◽  
Roger M. Bartlett
Keyword(s):  
Soft Tissues ◽  
Creep Behaviour ◽  
Maximum Voluntary Contraction ◽  
Testing Machine ◽  
Voluntary Contraction ◽  
Upper Arm ◽  
Creep Response ◽  
In Series ◽  
Bulk Tissue

The aim of this study was to characterise the bulk modulus properties of the upper arm under relaxed and controlled contraction which is defined as 25% of the maximum voluntary contraction. A new testing machine was designed to generate constant load on the upper arm and measure the deformation over time. The machine consists of a device which is effectively a cuff that applies controllable pressure on a 47 mm wide band of the upper arm. Six different loads (10, 20, 30, 40, 50 and 60 kgf) were applied over a period of time of up to a maximum of 120 seconds. The deflection-time curves obtained show strongly non-linear response of the bulk tissue. The non-linearity manifested by these deflection-time curves is in terms of both time- and load-dependency. For each load, the creep behaviour follows an exponential law typical of viscoelastic materials. At low loads (below 30kgf), the creep response increases fairly linearly as the load is increased from 10 kgf to 30 kgf. But at high loads (above 30 kgf), the creep response increases only slightly as the load is increased from 30 kgf to 60 kgf. Beyond a load of 60 kgf, the deflection or creep becomes negligible. This implies that the upper arm has reached the state of incompressibility. The creep behaviour of the upper arm was simulated using four Voigt viscoelastic models in series. The three obvious soft tissues of the upper arm, namely skin, fat and muscle, were modelled in series. The effects of blood vessels and connective tissue were also modelled in series with the other tissues.

In Vivo Mechanical Properties of Muscular Bulk Tissue: Mechanical Model Representation of Stress-Relaxation Behavior

2008 ◽  
Author(s):  
Serdar Arıtan ◽  
S. Olutunde Oyadiji ◽  
Roger M. Bartlett
Keyword(s):  
Mechanical Properties ◽  
Mechanical Model ◽  
Maximum Voluntary Contraction ◽  
Experimental Studies ◽  
Constitutive Models ◽  
Voluntary Contraction ◽  
Tissue Properties ◽  
Stress Relaxation Behavior ◽  
Bulk Tissue

In Vivo mechanical properties of bulk tissue have not been yet investigated sufficiently. One of the major problems the researchers confront is the lack of agreement for the constitutive models and standardized methodology for experimental studies (1). Despite the fact that the tissue properties are non-linear, many modeling studies preferred to adopt linear isotropic models. The object of this study was to obtain bulk modulus of the upper arm under relax and controlled contraction that was 25% of the maximum voluntary contraction (MVC).

scholarly journals Neuromuscular factors contributing to in vivo eccentric moment generation

1997 ◽  
Vol 83 (1) ◽  
pp. 40-45 ◽  
Author(s):  
Sandra Webber ◽  
Dean Kriellaars
Keyword(s):  
Linear Relationship ◽  
Knee Extensor ◽  
Motor Units ◽  
Voluntary Contraction ◽  
Contractile Element ◽  
Knee Extensors ◽  
Activation Level ◽  
In Series

Webber, Sandra, and Dean Kriellaars. Neuromuscular factors contributing to in vivo eccentric moment generation. J. Appl. Physiol. 83(1): 40–45, 1997.—Muscle series elasticity and its contribution to eccentric moment generation was examined in humans. While subjects [male, n = 30; age 26.3 ± 4.8 (SD) yr; body mass 78.8 ± 13.1 kg] performed an isometric contraction of the knee extensors at 60° of knee flexion, a quick stretch was imposed with a 12°-step displacement at 100°/s. The test was performed at 10 isometric activation levels ranging from 1.7 to 95.2% of maximal voluntary contraction (MVC). A strong linear relationship was observed between the peak imposed eccentric moment derived from quick stretch and the isometric activation level ( y = 1.44 x + 7.08; r = 0.99). This increase in the eccentric moment is consistent with an actomyosin-dependent elasticity located in series with the contractile element of muscle. By extrapolating the linear relationship to 100% MVC, the predicted maximum eccentric moment was found to be 151% MVC, consistent with in vitro data. A maximal voluntary, knee extensor strength test was also performed (5–95°, 3 repetitions, ±50, 100, 150, 200, and 250°/s). The predicted maximum eccentric moment was 206% of the angle- and velocity-matched, maximal voluntary eccentric moments. This was attributed to a potent neural regulatory mechanism that limits the recruitment and/or discharge of motor units during maximal voluntary eccentric contractions.

Adipose tissue thickness affects in vivo quantitative near-IR spectroscopy in human skeletal muscle

2001 ◽  
Vol 101 (1) ◽  
pp. 21-28 ◽  
Author(s):  
M. C. P. VAN BEEKVELT ◽  
M. S. BORGHUIS ◽  
B. G. M. VAN ENGELEN ◽  
R. A. WEVERS ◽  
W. N. J. M. COLIER
Keyword(s):  
Adipose Tissue ◽  
Ir Spectroscopy ◽  
Maximum Voluntary Contraction ◽  
Skinfold Thickness ◽  
Voluntary Contraction ◽  
Poor Correlation ◽  
Tissue Thickness ◽  
Isometric Handgrip ◽  
Near Ir

The influence of adipose tissue thickness (ATT) on near-IR spectroscopy (NIRS) measurements in vivo was studied in the human flexor digitorum superficialis muscle at rest and during sustained isometric handgrip exercise. NIRS was used for the quantitative measurement of muscle O2 consumption (mVo2) and forearm blood flow (FBF) in 78 healthy subjects. Skinfold thickness ranged from 1.4 to 8.9 mm within the group. Resting mVo2 was 0.11±0.04 ml of O2 min-1 100 g-1, and FBF was 1.28±0.82 ml min-1 100 ml-1. There was a negative correlation (r =-0.70, P ≤ 0.01), indicating a decrease in mVo2 with increasing ATT. mVo2 in the 10 leanest subjects appeared to be twice as high as that in the 10 subjects with the highest ATT. A poor correlation (r = 0.29, P ≤ 0.01) was found between ATT and FBF. The gender difference that we found for mVo2 was due to the difference in ATT between female and male subjects. No correlation was found between maximum voluntary contraction and mVo2, nor between maximum voluntary contraction and ATT, indicating that the contraction force did not confound our results. These results show that ATT has a substantial confounding influence on in vivo NIRS measurements, and that it is essential to incorporate this factor into future NIRS muscle studies in order to justify comparisons between different groups. To facilitate such comparisons, upper and lower boundaries for normal values of mVo2 and FBF in relation to ATT are presented.

Internal Rotation of the Upper-Arm Segment during a Stretch-Shorten Cycle Movement

1999 ◽  
Vol 15 (4) ◽  
pp. 381-395 ◽  
Author(s):  
Bruce C. Elliott ◽  
Kevin G. Baxter ◽  
Thor F. Besier
Keyword(s):  
Internal Rotation ◽  
Latissimus Dorsi ◽  
Degrees Of Freedom ◽  
External Rotation ◽  
Maximum Voluntary Contraction ◽  
Maximum Velocity ◽  
Voluntary Contraction ◽  
Upper Arm ◽  
Mean Delay ◽  
Anterior Deltoid

This research examined the influence on performance of no-pause and mean delays of 0.97 s and 1.5 s between the eccentric and concentric phases of the stretch-shorten cycle movement of internal rotation (IR) of me upper arm. Videography and surface electromyography were used in the assessment of 19 athletes throwing a baseball in a manner that constrained all degrees of freedom other than upper-arm IR. Results demonstrated that the pectoralis major, latissimus dorsi, and anterior deltoid muscles were all active at above 100% maximum voluntary contraction (MVC) during IR. The maximum velocity of the wrist decreased with increasing pause time between me eccentric and concentric phases of the IR movement. A mean 21.9% augmentation to the maximum wrist velocity was recorded when the no-pause delay and a mean delay of 1.5 s were compared. There were no electromyographically discernible differences recorded either prior to or after release for any of the monitored muscles during IR across the pause conditions. It is evident therefore that the benefits of a prestretch during external rotation (ER) have a significant influence on the subsequent velocity of IR.

APONEUROSIS LENGTH AND FASCICLE INSERTION ANGLES OF THE BICEPS BRACHII

2002 ◽  
Vol 02 (03n04) ◽  
pp. 449-455 ◽  
Author(s):  
DEANNA S. ASAKAWA ◽  
GEORGE P. PAPPAS ◽  
JOHN E. DRACE ◽  
SCOTT L. DELP
Keyword(s):  
Biceps Brachii ◽  
Maximum Voluntary Contraction ◽  
Magnetic Resonance Images ◽  
Voluntary Contraction ◽  
Ultrasound Images ◽  
Distal Biceps ◽  
Distal Muscle ◽  
Biceps Brachii Tendon ◽  
Long Head

Magnetic resonance images and ultrasound images were used to examine the architecture of the distal biceps brachii muscle in 12 unimpaired subjects. The distal biceps brachii tendon continued as an internal aponeurosis that spanned 34± 4% of the length of the biceps brachii long head muscle on average. The distal muscle fascicles inserted at angles to this aponeurosis; fascicles anterior to the aponeurosis inserted at a significantly greater (p ≤ 0.05) angle (17°) than the fascicles posterior to the aponeurosis (14°) in the distal 2 cm of muscle when the elbow was extended. Mean fascicle insertion angles were on average 3–4° greater with the elbow flexed 90° against a 5% maximum voluntary contraction load as compared to their values with the elbow extended. These data provide the basis for designing experiments to measure muscle and tendon motion in vivo.

scholarly journals Influence of static stretching on viscoelastic properties of human tendon structures in vivo

2001 ◽  
Vol 90 (2) ◽  
pp. 520-527 ◽  
Author(s):  
Keitaro Kubo ◽  
Hiroaki Kanehisa ◽  
Yasuo Kawakami ◽  
Tetsuo Fukunaga
Keyword(s):  
Viscoelastic Properties ◽  
Plantar Flexion ◽  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Medial Gastrocnemius ◽  
Static Stretching ◽  
Tendon Elongation ◽  
Before And After ◽  
Human Tendon

The purpose of this study was to investigate the influences of static stretching on the viscoelastic properties of human tendon structures in vivo. Seven male subjects performed static stretching in which the ankle was passively flexed to 35° of dorsiflexion and remained stationary for 10 min. Before and after the stretching, the elongation of the tendon and aponeurosis of medial gastrocnemius muscle (MG) was directly measured by ultrasonography while the subjects performed ramp isometric plantar flexion up to the maximum voluntary contraction (MVC), followed by a ramp relaxation. The relationship between the estimated muscle force (Fm) of MG and tendon elongation ( L) during the ascending phase was fitted to a linear regression, the slope of which was defined as stiffness of the tendon structures. The percentage of the area within the Fm- L loop to the area beneath the curve during the ascending phase was calculated as an index representing hysteresis. Stretching produced no significant change in MVC but significantly decreased stiffness and hysteresis from 22.9 ± 5.8 to 20.6 ± 4.6 N/mm and from 20.6 ± 8.8 to 13.5 ± 7.6%, respectively. The present results suggest that stretching decreased the viscosity of tendon structures but increased the elasticity.

Effects of static and dynamic training on the stiffness and blood volume of tendon in vivo

2009 ◽  
Vol 106 (2) ◽  
pp. 412-417 ◽  
Author(s):  
Keitaro Kubo ◽  
Toshihiro Ikebukuro ◽  
Katsutoshi Yaeshima ◽  
Hideaki Yata ◽  
Naoya Tsunoda ◽  
...  
Keyword(s):  
Blood Volume ◽  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Muscle Volume ◽  
Knee Extensors ◽  
Neural Activation ◽  
Patella Tendon ◽  
Activation Level ◽  
Before And After

The purpose of this study was to investigate the effects of static and dynamic training on the stiffness and blood volume of the human tendon in vivo. Ten subjects completed 12 wk (4 days/wk) of a unilateral training program for knee extensors. They performed static training on one side [ST; 70% of maximum voluntary contraction (MVC)] and dynamic training on the other side (DT; 80% of one repetition maximum). Before and after training, MVC, neural activation level (by interpolated twitch), muscle volume (by magnetic resonance imaging), stiffness of tendon-aponeurosis complex and patella tendon (by ultrasonography), and blood volume of patella tendon (by red laser lights) were measured. Both protocols significantly increased MVC (49% for ST, 32% for DT; both P < 0.001), neural activation level (9.5% for ST, 7.6% for DT; both P < 0.01), and muscle volume (4.5% for ST, 5.6% for DT; both P < 0.01). The stiffness of tendon-aponeurosis complex increased significantly after ST (55%; P = 0.003) and DT (30%; P = 0.033), while the stiffness of patella tendon increased significantly after ST (83%; P < 0.001), but not for DT ( P = 0.110). The blood volume of patella tendon increased significantly after DT (47%; P = 0.016), but not for ST ( P = 0.205). These results implied that the changes in the blood volume of tendon would be related to differences in the effects of resistance training on the tendon properties.

In vivo determination of fascicle curvature in contracting human skeletal muscles

2002 ◽  
Vol 92 (1) ◽  
pp. 129-134 ◽  
Author(s):  
Tadashi Muramatsu ◽  
Tetsuro Muraoka ◽  
Yasuo Kawakami ◽  
Akira Shibayama ◽  
Tetsuo Fukunaga
Keyword(s):  
Maximum Voluntary Contraction ◽  
Muscle Length ◽  
Muscle Thickness ◽  
Voluntary Contraction ◽  
Pennation Angle ◽  
Medial Gastrocnemius ◽  
Fascicle Length ◽  
Fascicle Curvature

Fascicle curvature of human medial gastrocnemius muscle (MG) was determined in vivo by ultrasonography during isometric contractions at three (distal, central, and proximal) locations ( n = 7) and at three ankle angles ( n = 7). The curvature significantly ( P < 0.05) increased from rest to maximum voluntary contraction (MVC) (0.4–5.2 m−1). In addition, the curvature at MVC became larger in the order dorsiflexed, neutral, plantar flexed ( P < 0.05). Thus both contraction levels and muscle length affected the curvature. Intramuscular differences in neither the curvature nor the fascicle length were found. The direction of curving was consistent along the muscle: fascicles were concave in the proximal side. Fascicle length estimated from the pennation angle and muscle thickness, under the assumption that the fascicle was straight, was underestimated by ∼6%. In addition, the curvature was significantly correlated to pennation angle and muscle thickness. These findings are particularly important for understanding the mechanical functions of human skeletal muscle in vivo.

Maximum one-handed pull force and its relation to shoulder geometry

2005 ◽  
Vol 4 (3) ◽  
pp. 143-155
Author(s):  
Krystyna Gielo-Perczak
Keyword(s):  
Maximum Voluntary Contraction ◽  
Frontal Plane ◽  
Voluntary Contraction ◽  
Resonance Imaging ◽  
Upper Arm ◽  
Shoulder Joints ◽  
Mri Scans ◽  
The Mean ◽  
Shoulder Geometry ◽  
Magnetic Resonance Imaging Mri

The current study proposes a method of geometrical description of the shoulder articulating surfaces in order to deduce an unrecognized relationship between shoulder geometry and strength during a one-handed pulling task. The paper reports the results of a study of the strength of 12 participants during one-handed pulling correlated with the geometries of their shoulder joints derived from magnetic resonance imaging (MRI) scans. The measurements of a mean force during pulling were recorded when an upper arm was adducted in the frontal plane from 5 to 30 degrees during maximum voluntary contraction (MVC). It was observed in the study that an area determined by the height and width of the glenoid fossa closely relates to the mean force during pulling.

A mechanical model representation of the in vivo creep behaviour of muscular bulk tissue

2008 ◽  
Vol 41 (12) ◽  
pp. 2760-2765 ◽  
Author(s):  
Serdar Arıtan ◽  
S. Olutunde Oyadiji ◽  
Roger M. Bartlett
Keyword(s):  
Mechanical Model ◽  
Creep Behaviour ◽  
Model Representation ◽  
Bulk Tissue
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