Muscles

type 1 fiber

"slow twitch" fiber that is optimized for aerobic respiration. Slower to fatigue. (LONG DISTANCES) blue fibers

Stabilizers

Hold a joint in place so that the action may be performed.

type 2a fibers

Intermediate fibers Fast-oxidative glycolytic fibers (DANCERS) pink fibers

Gross Anatomy of Skeletal Muscle

Most skeletal muscles are attached to two bones through tendons. Tendons are tough bands of dense regular connective tissue whose strong collagen fibers firmly attach muscles to bones. Tendons are under extreme stress when muscles pull on them, so they are very strong and are woven into the coverings of both muscles and bones

Gross Anatomy of Skeletal Muscle

Most skeletal muscles are attached to two bones through tendons. Tendons are tough bands of dense regular connective tissue whose strong collagen fibers firmly attach muscles to bones. Tendons are under extreme stress when muscles pull on them, so they are very strong and are woven into the coverings of both muscles and bones.

Prime Mover

Muscle most effective in producing a given action

Agonist

Muscle which contracts to produce a given action.

Antagonist

Muscle which contracts to produce an opposing action.

function

Muscles are sometimes classified by the type of function that they perform

Muscles

Muscles can only pull they cannot push. ● Muscles contract in the center and pull at both ends. ● The action of a muscle on a joint will be determined by the attachments and the path of the muscle. ● Muscles must oppose gravity to produce a movement or maintain a position.

Gross Anatomy of Skeletal Muscle

Muscles move by shortening their length, pulling on tendons, and moving bones closer to each other. One of the bones is pulled towards the other bone, which remains stationary. The place on the stationary bone that is connected via tendons to the muscle is called the origin. The place on the moving bone that is connected to the muscle via tendons is called the insertion. The belly of the muscle is the fleshy part of the muscle in between the tendons that does the actual contraction

Assistors (Synergists)

Muscles which contribute to a given action.

Roles of Muscles

Prime mover, Synergist, Antagonist, Stabilizer, Neutralizer

Skeletal Muscle

Skeletal muscle is the only voluntary muscle tissue in the human body—it is controlled consciously. Every physical action that a person consciously performs (e.g. speaking, walking, or writing) requires skeletal muscle. The function of skeletal muscle is to contract to move parts of the body closer to the bone that the muscle is attached to. Most skeletal muscles are attached to two bones across a joint, so the muscle serves to move parts of those bones closer to each other

Supinator

a muscle that supinates the wrist by rolling it over to face palm up. In the leg, there are muscles called adductors whose role is to adduct (pull together) the legs

primary focus of kinesiological

analysis of muscular action is to determine which muscles perform a given action and which muscles stabilize the body to only allow that action

Insertion

attachment to movable bone

origin

connection of the muscle to a stationary bone

rectus abdominis (agonists)

erector spinae

type 2b fibers

fast glycolytic fibers (SPRINT RUNNERS) red fibers

tibialis adductor (agonist)

gastrocnemius

lliopsoas (agonist)

gluteus maximus

hip adductor (agonist)

gluteus medius

quadreicpes (agonist)

hamstrings

quadriceps (agonists)

hamstrings

Deltoid (agonists)

lastissmus dorsi

isotonic contractions

muscle shortens and movement occurs

isometric contractions

muscular contraction that increases tension but does not produce movement.

pectoralis major (agonists)

trapeziu/rhomboids

biceps (agonsist)

triceps