Architecture of Contracting Human Muscles and Its Functional Significance

2000 ◽  
Vol 16 (1) ◽  
pp. 88-97 ◽  
Author(s):  
Yasuo Kawakami ◽  
Yoshiho Ichinose ◽  
Keitaro Kubo ◽  
Masamitsu Ito ◽  
Morihiro Imai ◽  
...  
Keyword(s):  
Plantar Flexion ◽  
Muscle Thickness ◽  
Normal Subjects ◽  
Human Muscle ◽  
Muscle Architecture ◽  
Triceps Brachii ◽  
Fascicle Length ◽  
Ultrasonic Images ◽  
Relationship Of

This paper reviews three of our recent studies on human muscle architecture in vivo. 1. Hypertrophic changes: From B-mode ultrasonograms, pennation angles and thickness of triceps brachii were determined for normal subjects and highly-trained bodybuilders. There was a significant correlation between muscle thickness and pennation angles. It was confirmed that hypertrophy was accompanied by an increase in pennation angles. 2. Variation of fascicle architecture: Fascicle lengths and pennation angles were obtained from different positions in the gastrocnemius muscle while the subjects relaxed and performed isometric plantar flexion. The fascicle length was uniform throughout the muscle and shortened by contraction (30-34% at 50% of the maximal force). On the other hand, pennation angles differed among positions and increased by contraction. The muscle thickness did not change by contraction. Pen-nation angles were significantly correlated with muscle thickness within muscle. 3. Joint position-fascicle length relationships: Ultrasonic images of the gastrocnemius and soleus muscles were obtained while the subject performed maximal isometric plantarflexion at various joint positions, from which fascicle lengths and angles were determined. The length-force relationship of each muscle was estimated. It was suggested that human muscle architecture has an ability to make substantial changes to adapt to environmental conditions.

Muscle-fiber pennation angles are greater in hypertrophied than in normal muscles

1993 ◽  
Vol 74 (6) ◽  
pp. 2740-2744 ◽  
Author(s):  
Y. Kawakami ◽  
T. Abe ◽  
T. Fukunaga
Keyword(s):  
Muscle Fiber ◽  
Muscle Thickness ◽  
Normal Subjects ◽  
Muscle Size ◽  
Triceps Brachii ◽  
Human Cadavers ◽  
Long Head ◽  
The Relationship ◽  
Male Subjects

Muscle-fiber pennation angles were measured in vivo with the use of ultrasonography to investigate the relationship between fiber pennation and muscle size for 32 male subjects (from untrained subjects to highly trained bodybuilders). From the image of a B-mode ultrasonogram, fiber pennation angles and thickness of triceps brachii were determined, the former as angles between echoes from the interspaces of fascicles and from the aponeurosis of long and medial heads of triceps and the latter as the distance between the fat-muscle and muscle-bone interfaces. The pennation angles were in the range of 15 and 53 degrees for the long head and 9 to 26 degrees for the medial head, which were similar to or greater than the published and the present data on human cadavers. Significant differences were observed between normal subjects and bodybuilders in muscle thickness and pennation angles (P < 0.01), and there were significant correlations between muscle thickness and pennation angles for both long (r = 0.884) and medial (r = 0.833) heads of triceps, suggesting that muscle hypertrophy involves an increase in fiber pennation angles.

scholarly journals In Vivo Human Gastrocnemius Architecture With Changing Joint Angle at Rest and During Graded Isometric Contraction of Normal and Weak Muscle

2020 ◽  
pp. 010-014
Author(s):  
Koryak Yuri
Keyword(s):  
Isometric Contraction ◽  
Plantar Flexion ◽  
Normal Subjects ◽  
Triceps Surae ◽  
Mean Values ◽  
Patient Groups ◽  
Triceps Surae Muscles ◽  
Muscle Changes ◽  
Ultrasonic Images

Architectural properties of the triceps surae muscles complex were determined In Vivo for thirty subjects. These subjects were assigned to two groups. The first group of subjects consisted of 8 healthy men and the second group of subjects was composed of 22 patients with motor disorders. The ankle was positioned at -15 ° (dorsiflexion), and 0 ° (neutral anatomical position), and 15 °, and 30 ° (plantarflexion), with the knee set at 120 °and with an angle in the ankle joint of 90 °. At each position, longitudinal ultrasonic images of the Medial (MG) and Lateral (LG) Gastrocnemius and Soleus (SOL) muscles were obtained while the subject was relaxed (passive) and performed 50 % maximal voluntary isometric plantar flexion (active), from which fascicle Lengths (L) and angles (Θ) with respect to the aponeuroses were determined. From the ultrasonic image, it was observed that and Θ changed during an isometric contraction of the triceps surae muscle. Changes in L and were expressed as a function of relative torque. The Θ change was not identical for the three muscles. The fascicle Θ of MG demonstrated the greatest variation in three muscles. The effects of activation and relaxation positions were significant in all three muscles. The differences in MG fascicle Θ because of changes in ankle positions were significant among control and patients both in the passive and active conditions. Fascicle Θ of LG and SOL not differed among control and patient in the relaxation condition but not in the activation condition. For LG, and SOL ol fascicle Θ were changes were larger in control with the patients. The mean values fascicle Θ of MG, LG, and SOL an isometric contraction (50 % MVC) in the control groups increased by 60 %, 41 %, and 41 %, respectively; in the patient groups were a smaller increase, by 28 %, 26 %, and 36 %, respectively. Different lengths and angles of fascicles, and their changes bу contraction by patients and normal subjects, might bе related to differences in force-producing capabilities of the muscles and elastic characteristics of tendons and aponeuroses.

Nonisometric behavior of fascicles during isometric contractions of a human muscle

1998 ◽  
Vol 85 (4) ◽  
pp. 1230-1235 ◽  
Author(s):  
Masamitsu Ito ◽  
Yasuo Kawakami ◽  
Yoshiho Ichinose ◽  
Senshi Fukashiro ◽  
Tetsuo Fukunaga
Keyword(s):  
Young’S Modulus ◽  
Joint Angle ◽  
Young's Modulus ◽  
Pennation Angle ◽  
Human Muscle ◽  
Isometric Contractions ◽  
Fascicle Length ◽  
Tendon Stiffness ◽  
Tendon Elongation

Fascicle length, pennation angle, and tendon elongation of the human tibialis anterior were measured in vivo by ultrasonography. Subjects ( n = 9) were requested to develop isometric dorsiflexion torque gradually up to maximal at the ankle joint angle of 20° plantarflexion from the anatomic position. Fascicle length shortened from 90 ± 7 to 76 ± 7 (SE) mm, pennation angle increased from 10 ± 1 to 12 ± 1°, and tendon elongation increased up to 15 ± 2 mm with graded force development up to maximum. The tendon stiffness increased with increasing tendon force from 10 N/mm at 0–20 N to 32 N/mm at 240–260 N. Young’s modulus increased from 157 MPa at 0–20 N to 530 MPa at 240–260 N. It can be concluded that, in isometric contractions of a human muscle, mechanical work, some of which is absorbed by the tendinous tissue, is generated by the shortening of muscle fibers and that ultrasonography can be used to determine the stiffness and Young’s modulus for human tendons.

scholarly journals Three-dimensional geometrical changes of the human tibialis anterior muscle and its central aponeurosis measured with three-dimensional ultrasound during isometric contractions

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2260 ◽  
Author(s):  
Brent J. Raiteri ◽  
Andrew G. Cresswell ◽  
Glen A. Lichtwark
Keyword(s):  
Three Dimensional ◽  
Muscle Length ◽  
Pennation Angle ◽  
Human Muscle ◽  
Muscle Fibres ◽  
Isometric Contractions ◽  
Fascicle Length ◽  
Cross Sectional ◽  
Shape Changes

Background.Muscles not only shorten during contraction to perform mechanical work, but they also bulge radially because of the isovolumetric constraint on muscle fibres. Muscle bulging may have important implications for muscle performance, however quantifying three-dimensional (3D) muscle shape changes in human muscle is problematic because of difficulties with sustaining contractions for the duration of anin vivoscan. Although two-dimensional ultrasound imaging is useful for measuring local muscle deformations, assumptions must be made about global muscle shape changes, which could lead to errors in fully understanding the mechanical behaviour of muscle and its surrounding connective tissues, such as aponeurosis. Therefore, the aims of this investigation were (a) to determine the intra-session reliability of a novel 3D ultrasound (3DUS) imaging method for measuringin vivohuman muscle and aponeurosis deformations and (b) to examine how contraction intensity influencesin vivohuman muscle and aponeurosis strains during isometric contractions.Methods.Participants (n= 12) were seated in a reclined position with their left knee extended and ankle at 90° and performed isometric dorsiflexion contractions up to 50% of maximal voluntary contraction. 3DUS scans of the tibialis anterior (TA) muscle belly were performed during the contractions and at rest to assess muscle volume, muscle length, muscle cross-sectional area, muscle thickness and width, fascicle length and pennation angle, and central aponeurosis width and length. The 3DUS scan involved synchronous B-mode ultrasound imaging and 3D motion capture of the position and orientation of the ultrasound transducer, while successive cross-sectional slices were captured by sweeping the transducer along the muscle.Results.3DUS was shown to be highly reliable across measures of muscle volume, muscle length, fascicle length and central aponeurosis length (ICC ≥ 0.98, CV < 1%). The TA remained isovolumetric across contraction conditions and progressively shortened along its line of action as contraction intensity increased. This caused the muscle to bulge centrally, predominantly in thickness, while muscle fascicles shortened and pennation angle increased as a function of contraction intensity. This resulted in central aponeurosis strains in both the transverse and longitudinal directions increasing with contraction intensity.Discussion.3DUS is a reliable and viable method for quantifying multidirectional muscle and aponeurosis strains during isometric contractions within the same session. Contracting muscle fibres do work in directions along and orthogonal to the muscle’s line of action and central aponeurosis length and width appear to be a function of muscle fascicle shortening and transverse expansion of the muscle fibres, which is dependent on contraction intensity. How factors other than muscle force change the elastic mechanical behaviour of the aponeurosis requires further investigation.

scholarly journals Force–Time Characteristics of Dynamic and Isometric Muscle Actions: Association with Muscle Architecture in Female Athletes

2021 ◽  
Vol 11 (11) ◽  
pp. 5272
Author(s):  
Vasiliki Gaspari ◽  
Gregory C. Bogdanis ◽  
Ioli Panidi ◽  
Georgia Giannakopoulou ◽  
Gerasimos Terzis ◽  
...  
Keyword(s):  
Female Athletes ◽  
Average Rate ◽  
Vastus Lateralis ◽  
Muscle Thickness ◽  
Muscle Architecture ◽  
Rate Of Force Development ◽  
Fascicle Length ◽  
Force Development ◽  
Force Time ◽  
Muscle Actions

The association between force–time characteristics of isometric leg press (ILP) and countermovement jump (CMJ) with vastus lateralis (VL) muscle architecture, was examined in 19 female athletes (aged 23.2 ± 5.4 years). Peak force (PF), average rate of force development (ARFD) and rate of force development (RFD) at different time epochs were calculated from the force–time curve, as well as CMJ jump height and power. Significant correlations were found between ILP-PF and CMJ power (r = 0.658, p < 0.01), while both variables were correlated with VL thickness and fascicle length (r = 0.471 to 0.648, p < 0.05). Significant correlations were also observed between ILP-RFD epochs and VL fascicle length (r = 0.565 to 0.646, p < 0.05) and between CMJ height with VL thickness (r = 0.523, p < 0.05). Furthermore, positive correlations were found between ILP and CMJ in ARFD (r = 0.625, p < 0.01) and RFD epochs (r = 0.464 to 0.566, p < 0.05). ILP-PF and muscle thickness accounted for 52.8% (p = 0.002) of the variance in CMJ power. These results suggest that isometric force time characteristics are associated with power generation during dynamic muscle actions. Furthermore, VL muscle thickness and fascicle length are associated with rapid force production in female athletes, irrespective of the type of muscle action.

Short-term effects of neuromuscular electrical stimulation and ultrasound therapies on muscle architecture and functional capacity in knee osteoarthritis: a randomized study

2018 ◽  
Vol 33 (3) ◽  
pp. 418-427 ◽  
Author(s):  
Gul Devrimsel ◽  
Yavuz Metin ◽  
Munevver Serdaroglu Beyazal
Keyword(s):  
Knee Osteoarthritis ◽  
Functional Capacity ◽  
Therapy Group ◽  
Randomized Study ◽  
Neuromuscular Electrical Stimulation ◽  
Muscle Thickness ◽  
Muscle Architecture ◽  
Ultrasound Therapy ◽  
Fascicle Length ◽  
Hot Pack

Objective: To determine the effects of ultrasound therapy and neuromuscular electrical stimulation (NMES) application on the muscle architecture and functional capacity in patients with knee osteoarthritis. Design: A randomized study. Subjects: A total of 60 patients with knee osteoarthritis. Interventions: Participants were randomized into one of the following two intervention groups, five days a week, for three weeks: the combination of NMES application, hot pack, and exercise therapy was applied to the NMES group. The combination of therapeutic ultrasound, hot pack and exercise therapy was applied to the ultrasound therapy group. Main measures: Subjects were evaluated for pain and functional capacity with the use of the visual analog pain scale (VAS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and 15 meter walking test. The muscle architecture (muscle thickness, pennation angle and fascicle length) was assessed from vastus lateralis and quadriceps femoris muscles bilaterally by ultrasonography. Results: Two groups presented significant improvements in all outcome measures before and after treatment ( P < 0.01). There were significant improvements in VAS rest pain ( P < 0.05), VAS activity pain ( P < 0.05), WOMAC pain ( P < 0.05), WOMAC stiffness score ( P < 0.05), and WOMAC physical function ( P < 0.05) for the ultrasound therapy group in comparison to the NMES group. NMES group exhibited more increases in the muscle thickness and fascicle length values when compared to ultrasound therapy group ( P < 0.05). Conclusion: Ultrasound therapy appears to be an effective treatment in reducing pain and improving functional capacity. NMES application has more effects on the muscle architecture.

The Influence of Fascicle Behavior on the Lack of Velocity Dependence in Eccentric Joint Torque in Humans: In Vivo Observation

2009 ◽  
Vol 25 (2) ◽  
pp. 111-118 ◽  
Author(s):  
Kentaro Chino ◽  
Naotoshi Mitsukawa ◽  
Kai Kobayashi ◽  
Yusuke Miyoshi ◽  
Toshiaki Oda ◽  
...  
Keyword(s):  
Plantar Flexion ◽  
Triceps Surae ◽  
Joint Torque ◽  
Fascicle Length ◽  
Significant Difference ◽  
Isometric Torque ◽  
The Difference ◽  
The Relationship ◽  
Real Time Ultrasonography

To investigate the relationship between fascicle behavior and joint torque, the fascicle behavior of the triceps surae during isometric and eccentric (30 and 60 deg/s) plantar flexion by maximal voluntary and submaximal electrical activation (MVA and SEA) was measured by real-time ultrasonography. Eccentric torque at 30 and 60 deg/s was significantly higher than isometric torque under SEA, but not under MVA. However, fascicle length did not significantly differ between isometric and eccentric trials under either condition. Therefore, the difference in developed torque by MVA and SEA cannot be explained by fascicle behavior. Under both MVA and SEA conditions, eccentric torque at 30 and 60 deg/s was equivalent. Similarly, fascicle lengthening velocities at 30 and 60deg/s did not show any significant difference. Such fascicle behavior can be attributed to the influence of tendinous tissue and pennation angle, and lead to a lack of increase in eccentric torque with increasing angular velocity.

Effects of the Functional Heel Drop Exercise on the Muscle Architecture of the Gastrocnemius

2020 ◽  
Vol 29 (8) ◽  
pp. 1053-1059
Author(s):  
Diego Alonso-Fernandez ◽  
Yaiza Taboada-Iglesias ◽  
Tania García-Remeseiro ◽  
Águeda Gutiérrez-Sánchez
Keyword(s):  
Repeated Measures ◽  
Muscle Thickness ◽  
Pennation Angle ◽  
Muscle Architecture ◽  
Medial Gastrocnemius ◽  
Control Group ◽  
Fascicle Length ◽  
Rehabilitation Programs ◽  
Architectural Characteristics ◽  
Induced Changes

Context: The architectural characteristics of a muscle determine its function. Objective: To determine the architectural adaptations of the lateral gastrocnemius (LG) and medial gastrocnemius (MG) muscles after a functional eccentric strength training protocol consisting of heel drop exercises, followed by a subsequent detraining period. Design: Pretest and posttest. Setting: Training rooms and laboratory. Participants: The participants (N = 45) who were randomly divided into an experimental group (EG, n = 25) and a control group (CG, n = 20). Interventions: The 13-week intervention included participants (N = 45) who were randomly divided into an EG (n = 25) and a CG (n = 20). The EG performed a week of control and training, 8 weeks of eccentric training, and 4 weeks of detraining. The CG did not perform any type of muscular training. The architectural characteristics of the LG and MG muscles were evaluated at rest in both groups using 2-D ultrasound before (pretest–week 1) and after (posttest–week 9) the training, and at the end of the detraining period (retest–week 13). Main Outcome Measures: One-way repeated measures analysis of variance was used to determine training-induced changes in each of the variables of the muscle architecture. Results: After the training period, the members of the EG experienced a significant increase in the fascicle length of LG (t = −9.85, d = 2.78, P < .001) and MG (t = −8.98, d = 2.54, P < .001), muscle thickness (t = −6.71, d = 2.86, P < .001) and (t = −7.85, d = 2.22, P < .001), and the pennation angle (t = −10.21, d = 1.88, P < .05) and (t = −1.87, d = 0.53, P < .05), respectively. After the detraining period, fascicle length, muscle thickness, and pennation angle showed a significant decrease. In the CG, no significant changes were observed in any of the variables. Conclusions: The heel drop exercise seems to generate adaptations in the architectural conditions of LG and MG, which are also reversible after a detraining period. These results may have practical implications for injury prevention and rehabilitation programs.

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.

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