KINE 3135 Biomechanics of Skeletal Muscles

The video tutorial covers anatomical positions, muscle fiber arrangements, and types of muscle contractions. It explains the role of motor neurons and motor units in muscle contraction, and how electrical stimuli affect muscle tension and force. Key concepts include superficial and deep muscles, parallel and pennate fibers, concentric, eccentric, and isometric contractions, and the relationship between force and muscle length.

What does the term 'superficial' refer to in anatomical terms?

• Towards the interior of the body

• Towards the surface of the body

• A type of muscle fiber arrangement

• A type of muscle contraction

Which type of muscle fiber arrangement is known for providing greater range of motion?

• Pennate muscle fibers

• Unipennate muscle fibers

• Multipennate muscle fibers

• Parallel muscle fibers

In a concentric contraction, what happens to the muscle?

• The muscle rotates

• The muscle remains the same length

• The muscle shortens

• The muscle lengthens

What is the role of the agonist muscle during a movement?

• It causes the movement

• It opposes the movement

• It relaxes during the movement

• It stabilizes the joint

In which type of contraction is the muscle force less than the resistance?

• Concentric contraction

• Static contraction

• Isometric contraction

• Eccentric contraction

What is a motor unit composed of?

• A sensory neuron and a single muscle fiber

• A sensory neuron and all the muscle fibers it innervates

• A motor neuron and all the muscle fibers it innervates

• A motor neuron and a single muscle fiber

Which activity is likely to activate the fewest motor units?

• Running

• Weightlifting

• Writing with a pencil

• Jumping

What happens during wave summation in muscle contractions?

• Muscle fibers relax completely between stimuli

• Electrical stimuli are applied before the muscle relaxes completely

• Muscle fibers contract and relax at the same rate

• Muscle fibers contract without any electrical stimuli

What is the relationship between force and velocity in concentric contractions?

• Inversely proportional

• Directly proportional

• Equal

• Unrelated

What is the effect of a supramaximal stimulus on muscle force?

• It has no effect on muscle force

• It does not increase muscle force beyond maximal

• It decreases muscle force

• It significantly increases muscle force