Sport-specific joint angle effect on the correlations between isometric torque and jumping performance

In the experiment, the author used wave plus wireless surface electromyography system (SEMs + 3-axis acceleration sensor) made in Italy and wave wireless EMG software system, high-definition high-speed camera and human joint angle measuring instrument. Taking human biceps brachii as an example, the static and dynamic isometric contraction of biceps brachii was completed surface electromyography. In the experiment, the surface electromyography of biceps brachii was measured at 30°, 60°, 90°, 120°, 150°, 180° and the surface electromyography of biceps brachii was measured at the same time when the biceps brachii was not loaded or when the biceps brachii was loaded. Secondly, the surface electromyography of biceps brachii was measured at the same time when the biceps brachii completed the whole process of flexion and extension of the elbow (centripetal and centrifugal). Finally, the paper combined with HD The effect of joint angle on the contraction of biceps brachii muscle was analyzed by camera technique. The results show that the static contraction force of biceps brachii is different when the elbow joint is at different angles; in addition, when the dynamic contraction, the contraction force of biceps brachii is inversely proportional to the angle of elbow joint.

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Joint angle effect on the failure behavior of pinned joint composite plates

Journal of Composite Materials ◽

10.1177/0021998312460796 ◽

2012 ◽

Vol 47 (24) ◽

pp. 3027-3039 ◽

Cited By ~ 1

Author(s):

Kadir Turan

Keyword(s):

Joint Angle ◽

Composite Plates ◽

Failure Behavior ◽

Angle Effect

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Modified Ankle Joint Neuromechanics during One-Legged Heel Raise Test after an Achilles Rupture and Its Associations with Jumping

Applied Sciences ◽

10.3390/app11052227 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2227

Author(s):

Kao-Shang Shih ◽

Pei-Yu Chen ◽

Wen-Ling Yeh ◽

Hsiao-Li Ma ◽

Chui-Jia Farn ◽

...

Keyword(s):

Ankle Joint ◽

Dynamic Characteristics ◽

Muscle Activation ◽

Joint Angle ◽

Reaction Force ◽

Medial Gastrocnemius ◽

Jumping Performance ◽

The One ◽

Lower Ankle Joint ◽

Kinematics And Kinetics

This study had two purposes. The first purpose of the study was to compare the electromyographic(EMG) and dynamic characteristics in injured and non-injured legs during the one-legged heel-raise test after a unilateral Achilles repair. The second purpose was to determine the correlations between the EMG results and the dynamic characteristics and between the characteristics in the eccentric phase and jumping distance. Twenty-six participants who underwent an Achilles repair between 4 and 12 months prior to the measurement were recruited to perform the following bilateral tests: (1) one-legged heel-raise test with measurements of muscle activation, kinematics, and kinetics and (2) one-legged forward jumping. During the heel-raise exercise, there were increases of the EMG amplitudes in the soleus and tibialis anterior muscles, lower ankle joint angle and angular velocity, lower normalized ground reaction force, and mechanical work in the repaired legs in comparison to the non-injured legs. The EMG results of the medial gastrocnemius and soleus muscles correlated with the dynamic results (rs = 0.467 and −0.537). Furthermore, the dynamic data in the eccentric phase were correlated with the jumping performance (rs = 0.575 and −0.471). It is concluded the soleus muscle undergoes neuromechanical changes, including changes in EMG and dynamic characteristics, and changes affecting jumping performance.

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MUSCLE ACTIVITY-JOINT ANGLE-ISOMETRIC TORQUE AND LOAD TORQUE-VELOCITY RELATIONS OF HUMAN ELBOW EXTENSOR MUSCLES

Biomechanisms ◽

10.3951/biomechanisms.14.27 ◽

1998 ◽

Vol 14 (0) ◽

pp. 27-37 ◽

Cited By ~ 3

Author(s):

Takanori UCHIYAMA ◽

Kenzo AKAZAWA

Keyword(s):

Muscle Activity ◽

Joint Angle ◽

Load Torque ◽

Extensor Muscles ◽

Isometric Torque ◽

Elbow Extensor

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Muscle force and moment arm contributions to torque production in frog hindlimb

AJP Cell Physiology ◽

10.1152/ajpcell.1988.254.6.c769 ◽

1988 ◽

Vol 254 (6) ◽

pp. C769-C772 ◽

Cited By ~ 19

Author(s):

R. L. Lieber ◽

J. L. Boakes

Keyword(s):

Muscle Force ◽

Joint Angle ◽

Muscle Length ◽

Moment Arm ◽

Maximum Torque ◽

Semitendinosus Muscle ◽

Relative Contribution ◽

Musculoskeletal Anatomy ◽

Isometric Torque ◽

Highly Correlated

The relative contribution of maximum muscle tetanic tension (Po) and muscle moment arm to maximum knee flexion torque was investigated in the frog hindlimb. Isometric torque was measured in frog semitendinosus muscle-bone complexes throughout the range of 0-160 degrees of flexion. Optimal joint angle (the angle at which isometric torque was maximum) was observed at 140 degrees of flexion. After torque measurements, the muscle was excised and the muscle length-tension relationship measured for determination of Po and optimal muscle length. In addition, the kinematics of the knee joint and therefore, the muscle moment arm was measured as a function of joint angle using principles of rigid body kinematics. Stepwise linear regression indicated that maximum torque was most highly correlated with Po (r = +0.77, P less than 0.01) and accounted for approximately 75% of the measured torque. In addition, there was no significant correlation between maximum torque and maximum muscle moment arm (r = +0.11, P greater than 0.7) suggesting that muscle force, not musculoskeletal anatomy, represents the major determinant of maximum torque production in the frog hindlimb.

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Do Changes in Joint Angle Effect Motor-Output Variability?

PsycEXTRA Dataset ◽

10.1037/e537272012-611 ◽

1994 ◽

Author(s):

Les G. Carlton

Keyword(s):

Joint Angle ◽

Motor Output ◽

Output Variability ◽

Motor Output Variability ◽

Angle Effect

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Electromyographic evaluation of joint angle specificity and cross-training after isometric training

Journal of Applied Physiology ◽

10.1152/jappl.1994.77.1.197 ◽

1994 ◽

Vol 77 (1) ◽

pp. 197-201 ◽

Cited By ~ 39

Author(s):

J. P. Weir ◽

T. J. Housh ◽

L. L. Weir

Keyword(s):

Joint Angle ◽

Vastus Lateralis ◽

Training Group ◽

Control Group ◽

Joint Angles ◽

Cross Training ◽

Integrated Electromyogram ◽

Isometric Torque ◽

Group 3 ◽

Unilateral Strength Training

The purpose of this study was to examine the effects of unilateral strength training on the strength and integrated electromyogram (IEMG) of the trained and untrained limbs at several joint angles. A training group [TRN; 4 females and 3 males, age 22 +/- 4 yr (SD)] exercised for 6 wk with isometric leg extensions at 80% of maximal isometric torque. A control group (3 females and 3 males, age 24 +/- 4 yr) did not exercise. The training was performed three times per week at 0.79 rad below the horizontal plane. The subjects were tested at joint angles of 0.00, 0.26, 0.79, 1.31, and 1.57 rad. Bipolar surface electrodes were used to record the IEMG of the vastus lateralis. The results indicated a cross-training effect and joint angle specificity for isometric torque in TRN only, with significant (P < 0.0005) increases in torque (collapsed across limb) at 0.26 (23.3%) and 0.79 (22.3%) rad. There was a dissociation, however, between changes in torque and IEMG with an increase (P < 0.05) in IEMG (collapsed across limb and angle) for TRN. The dissociation between the IEMG and strength changes was possibly due to differential responses to training in the four muscles of the quadriceps femoris.

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