Massage and Bodywork Licensing Examination MBLEx Test Kinesiology and Biomechanics 1

Question 1

When the biceps brachii flexes the elbow joint, with the elbow acting as the fulcrum and a weight held in the hand as the load, which class of lever is demonstrated?

Accepted Answer

Third class

Answer

In elbow flexion, the muscle force (effort) is applied at the biceps insertion on the radius, which lies between the fulcrum (elbow joint) and the load (weight in hand). This arrangement defines a third-class lever, the most common lever type found in the human body.

Question 2

Which sensory receptor detects rapid changes in muscle length and initiates the stretch reflex arc?

Accepted Answer

Muscle spindle

Answer

Muscle spindles are proprioceptors embedded within the muscle belly that monitor changes in muscle length. When a muscle is suddenly lengthened, spindle activation sends afferent signals to the spinal cord, triggering a reflexive contraction of the same muscle to resist the stretch.

Question 3

A muscle that assists the prime mover by contributing to the same joint action is classified as a:

Accepted Answer

Synergist

Answer

A synergist aids the agonist (prime mover) by performing the same or a supporting joint action, or by stabilizing proximal joints so the prime mover can work efficiently. Antagonists, by contrast, produce the opposite motion.

Question 4

During a closed kinetic chain exercise such as a standing squat, what best characterizes the distal segment?

Accepted Answer

It is fixed against an immovable surface

Answer

In a closed kinetic chain, the distal segment (e.g., the foot in a squat) is fixed against a surface, causing the proximal segments to move around it. This contrasts with an open kinetic chain, where the distal segment swings freely through space.

Question 5

Which type of muscle contraction occurs when the muscle generates tension but neither the joint angle nor the muscle length changes?

Accepted Answer

Isometric

Answer

An isometric contraction ('iso' = same, 'metric' = length/measure) produces force without any shortening or lengthening of the muscle or movement at the joint. It is commonly seen in postural stabilization and static holds.

Massage and Bodywork Licensing Examination Practice Test

Massage and Bodywork Licensing Examination Practice Test

Massage and Bodywork Licensing Examination MBLEx Test Kinesiology and Biomechanics 1