ISSA Unit 4: Kinesiology of Exercise

Q6: Adduction is movement of a body part away from the midline of the body. TRUE OR FALSE

FALSE Explanation: Adduction is movement toward the midline of the body Abduction is movement away from the midline of the body

Q1: In a concentric contraction, the muscle lengthens to produce movements. TRUE OR FALSE

FALSE Explanation: In a concentric contraction, the muscles shorten to produce movement. In an eccentric contraction (often known as a yielding contraction), the muscle lengthens (stretches) as it contracts. In an isometric contraction, the muscle exhibits strength but the limbs do not move.

Q4: True synergy occurs when a muscle contracts to stop the secondary action of another muscle. TRUE OR FALSE

TRUE Explanation: True synergy, in which a different muscle contracts to stop the secondary action of another muscle. For example, the biceps brachii is both a supinator of the forearm and a flexor of the elbow joint. Thus, in elbow flexion, the pronator quadratus comes into play to cancel the supinating tendency of the biceps so that only flexion occurs. The pronator teres also comes into play, but because it is a flexor of the elbow, it acts as a helping synergist. Helping synergy, in which two muscles contract simultaneously to produce one movement while their other actions cancel each other out. For example, in the sit-up exercise, when the internal and external oblique muscles contract, they have a tendency to not only perform spinal flexion but to rotate the shoulders. In order to prevent the rotation, the internal and external oblique muscles cancel out their rotational action and the resultant force is used for spinal flexion.

The three planes that pass through the human body.

1. The sagittal (anteroposterior) plane is a vertical plane passing through the body from front to back, dividing the body into left and right portions. 2. The frontal (coronal) plane is a vertical plane passing through the body from left to right, dividing it into front and back portions. 3. The transverse (horizontal) plane passes through the body in a line parallel to the ground, dividing the body into upper and lower portions.

Q3: An isometric contraction is when:

Answer: A muscle does not lengthen or shorten as it contracts. Explanation: In a concentric contraction, the muscles shorten to produce movement. In an eccentric contraction (often known as a yielding contraction), the muscle lengthens (stretches) as it contracts. In an isometric contraction, the muscle exhibits strength but the limbs do not move.

Q7: An example of flexion is the:

Answer: Concentric action of a bicep curl Explanation: Flexion- Decreasing the angle between two bones. Extension- Increasing the angle between two bones.

Q8: Flexion mainly occurs in which plane?

Answer: Sagittal Plane Explanation: Human movements are commonly described in terms of the planes that they occupy. A plane is a flat surface. The human body has three imaginary planes that pass through it; each plane is perpendicular to each of the other two. Two examples that may help describe the orientation of movement are given here. The first is a typical biceps curl. Concentric contraction of the biceps occurs in the sagittal plane. Second, abduction of the arm, as in a lateral dumbbell raise, occurs in the frontal plane. The standardized reference position from which movements of the body are described is the anatomical position, in which the body is facing forward, arms at the sides and palms forward.

Q2: Kinesiology is:

Answer: The science or study of human movement, and the active and passive structures involved. Explanation: Kinesiology is the study of human motion, and it deals primarily with the muscles and muscle functions. It describes movement, which muscles are involved in the movement, and how they are involved. Kinesiology tells you exactly which muscles are involved in the particular actions that take place in an exercise.

Q5: An example of an antagonist muscle is:

Answers: Triceps during a biceps curl. Explanation: An antagonist muscle has an action directly opposite to that of the agonist. When an agonist undergoes a concentric contraction, an antagonist undergoes an eccentric contraction to guide the movement and to stabilize the joint. As the movement goes through the full range of motion (ROM), the antagonist muscle develops greater tension and stops the movement before it goes beyond the normal ROM. During the biceps curl, the elbow flexes as a result of the biceps muscle concentrically contracting. As the triceps muscle is an elbow extensor, it's action is directly opposite to that of the biceps muscle, and is in a turn an antagonist muscle during the biceps curl.