36 Questions
What is the typical range of muscle cross-sectional area force production capacity?
0.3-0.4 N/mm²
How does the direction of muscle contraction affect torque production?
Eccentric contraction produces the highest torque, followed by isometric and then concentric.
How does the speed of muscle contraction affect torque production for concentric contractions?
Slower contraction speeds produce higher torque.
How does the speed of muscle contraction affect torque production for eccentric contractions?
Faster contraction speeds produce higher torque.
How does the position of the joint affect muscle torque production?
Muscle torque is affected by both the muscle length (length-tension relationship) and the bone orientation (lever arm).
How do the roles of muscles differ between textbook descriptions and real-world situations?
In real-world situations, muscles may act as agonists, antagonists, or synergists, while textbook descriptions focus on a single muscle action.
What is the primary function of muscles?
To produce force and joint movement
Which of the following terms refers to the distal attachment point of a muscle?
Insertion
What is a bi-articular muscle?
A muscle that crosses and moves two joints in the same direction
Which of the following is NOT a factor that influences a muscle's ability to produce force?
Muscle color
What is the purpose of a muscle's tendon?
To attach the muscle to a bone
How can an understanding of muscle architecture and function be applied?
To optimize an individual's athletic performance
What are bi-articular muscles primarily used for?
Energy transfer between joints
What is the primary function of the gastrocnemius muscle?
Ankle plantarflexion
Which muscle architecture feature increases the number of muscle fibers that can be packed into a given volume?
A high pennation angle
What does a low fiber length to muscle length ratio indicate about a muscle's function?
High force generation capacity
Which of the following is a mono-articular muscle?
Quadriceps
What is the primary function of the pennation angle in muscle architecture?
Increase the number of muscle fibers
In muscle mechanics, what does a low FL/ML Ratio indicate?
Higher force production
Which type of muscle contraction is associated with a FL/ML Ratio of 0.6?
Eccentric contraction
What is the primary factor influencing force production in mono-articular muscles?
Fiber orientation
Which muscle architecture characteristic affects the number of muscle fibers that can be packed into a given volume?
Pennate structure with a 30° angle
How does a bi-articular muscle contribute to energy transfer between joints?
By acting on two or more joints simultaneously
Which muscle group is primarily responsible for hip extension?
Hamstrings
Which of the following statements best describes the relationship between the number of cross-bridges attached to actin filaments and muscle contraction force?
The greater the number of cross-bridges attached, the larger the contraction force.
What is the relationship between the frequency of stimuli from the motor neuron and the tension produced in a muscle fiber?
If the frequency of stimuli is rapid enough, a tetanic response of the fibers results, producing sustained tension.
Which type of muscular contraction generates the greatest force when the muscle is maximally stimulated?
Eccentric contraction
In the context of muscle contraction, what is the primary function of an agonist muscle?
To initiate and perform the primary movement.
What is the difference between a tonic muscle contraction and a phasic muscle contraction?
Tonic contractions are sustained, while phasic contractions are brief and intense.
How does muscle fiber length influence the force production capacity of a muscle?
The relationship between muscle fiber length and force production capacity is non-linear and depends on other factors.
Which of the following is a key factor that influences a muscle's ability to produce force?
All of the above
What is the primary stimulus for the activation of a tonic or stability muscle?
Maintaining posture and joint stability
How does muscle length affect its ability to produce force?
Muscle force production is maximized at an optimal length
What is the primary function of an agonist muscle during a movement?
To produce the main force and movement of the joint
How do phasic or mobility muscles differ from tonic or stability muscles?
Both b and c
What is the primary role of a synergist muscle during a movement?
To provide a similar action to the agonist and assist it
Explore the structure of muscle and the mechanism of skeletal muscle contraction, including factors influencing a muscle's ability to produce motion and force. Learn how muscle architecture is specialized for optimizing force production and joint motion, and how this knowledge can enhance a person's performance.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
