Name:____________________________
Miss Toritto
Date:_________________
Physical Education: Personal Fitness
The Muscular System: Key Terms
1. Anatomical Directions and Joint Motions:
a.
b.
c.
d.
e.
f.
g.
Anterior = in front of
Posterior = in back of
Lateral = refers to away from the midline of the body
Flexion = bending of a joint
Extension = straightening of a joint
Adduction = towards the body
Abduction = away from the body
2. Muscle Types:
a. Skeletal Muscle: attaches to the bones by connective tissue called
“tendons.” This type causes voluntary contractions and is the target
muscle type of strength training.
b. Smooth Muscle: produces movement in your internal organs.
c. Cardiac Muscle: heart muscle causes the rhythmical contractions of the
heart.
d. Fast Twitch Muscle Fiber: contract quickly, fatigue easy, used for
anaerobic activities, responsible for explosive muscle contractions.
e. Slow Twitch Muscle Fiber: contract slowly, do not fatigue easily, has
large blood supply (oxygen), used in aerobic and endurance activities.
3. Muscular Contractions:
a. Concentric: contraction in which the muscle is shortening
i. Exampleb. Eccentric: contraction in which the muscle is lengthening
i. Examplec. Isometric: contraction in which the muscle is nether lengthening nor
shortening
i. Example4. Agonist and Antagonist:
a. Agonist: the prime mover in a given exercise.
i. Example- The agonist when doing a leg curl is the
_________muscle.
b. Antagonist: the muscle that makes the opposite movement from the prime
mover.
i. Example- The antagonist when doing a bicep curl is the
_________ muscle.
5. Atrophy and Hypertrophy:
a. Atrophy: a decrease in the size of the muscle. A muscle will atrophy
when demands on the muscle are decreased, or ceased all together. The
less work the smaller the muscle.
b. Hypertrophy: increase in size of the muscle. Hypertrophy results from
enlargement of muscle fibers. It will occur when a sufficient overload is
placed upon the muscle to force it to work harder than normal and grow or
adapt. Increased muscle mass will result in your body burning more
calories because muscles use calories for fuel 24 hours a day.
6. Muscle Soreness:
a. Acute muscle soreness: the pain one experiences during or immediately
after exercise. This is caused by a buildup of lactic acid in the muscle
tissue or shifts in fluid balance in the muscle cells.
b. DOMS (Delayed onset muscle soreness): the pain one experiences one to
two days after exercise. Microscopic tears in the muscle itself most likely
cause this type of soreness.