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Obtaining Quality Extended Field-of-View Ultrasound Images of Skeletal Muscle to Measure Muscle Fascicle Length
Published on: December 14, 2020
Human skeletal muscle size and architecture: variability and interdependence
Y Kawakami1, T Abe, H Kanehisa
1Faculty of Sport Sciences, Waseda University, Saitama 359-1192, Japan. ykawa@waseda.jp
Summary
Muscle thickness and pennation angles show significant variations across different muscles and genders. These muscle dimensions are positively correlated, indicating a general feature of pennate muscles.
Area of Science:
- Anatomy
- Biomechanics
- Physiology
Background:
- Muscle architecture, including thickness and pennation angle, influences force production.
- Variability in muscle dimensions exists across individuals and muscle groups.
- Understanding muscle-specific and gender-specific variations is crucial for fields like sports science and rehabilitation.
Purpose of the Study:
- To investigate the variability in muscle thickness and pennation angles of the triceps brachii, vastus lateralis, and gastrocnemius medialis muscles.
- To examine potential gender-specific differences in these muscle architectural parameters.
- To determine the relationship between muscle thickness and pennation angle across different muscles.
Main Methods:
- Ultrasound imaging was used to measure muscle thickness and pennation angles.
- A diverse cohort of 711 participants (aged 3-94 years), including normal individuals and bodybuilders, was studied.
- Measurements were taken for the triceps brachii, vastus lateralis, and gastrocnemius medialis muscles.
Main Results:
- Significant variations in muscle thickness and pennation angles were observed, with the triceps brachii showing the largest range.
- Women exhibited smaller variations in muscle dimensions compared to men, suggesting gender-specific differences.
- Strong positive correlations were found between muscle thickness and pennation angles for all measured muscles (r = 0.81 for TB, 0.61 for VL, 0.56 for GM).
Conclusions:
- Muscle thickness and pennation angle variability demonstrate muscle-specific and gender-specific characteristics.
- The positive correlation between muscle thickness and pennation angle is a consistent feature across pennate muscles.
- These findings provide valuable insights into human skeletal muscle architecture and its determinants.
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