Muscles
There are two types of contractions:Isometric and Isotonic
Isometric-muscle tension is increased but no movement: occurs over the joint
Isotonic- allows movement over joint-2 types
-Aconcentric: muscles shorten
-Eccentric: muscle control movement speed against gravity
Aerobic
* most effective exercise program uses both aerobic and anaerobic-> increases in metabolic rate at rest and increases performance during sport
Muscle Fibers
Muscle fibers are broken into 2 types of muscle fibers- slow twitch and fast twitch
Slow Twitch
Fast Twitch
* an average person has half of slow twitch and half of fast twitch. Olympic sprinters have 80% fast twitch fibers. Marathon runners have 80% slow twitch fibers
Skeletal Muscle
Isometric-muscle tension is increased but no movement: occurs over the joint
Isotonic- allows movement over joint-2 types
-Aconcentric: muscles shorten
-Eccentric: muscle control movement speed against gravity
Aerobic
- this is when exercise is longer than 2 min.
- increases cardio endurance
- decreases body fat
- decreases muscle mass and strength
- -Example: Running for 20 min.
- Exercise is less than 2 min.
- involves high power output
- does not affect aerobic capacity/endurance
- improves power,speed, strength and muscle mass
* most effective exercise program uses both aerobic and anaerobic-> increases in metabolic rate at rest and increases performance during sport
Muscle Fibers
Muscle fibers are broken into 2 types of muscle fibers- slow twitch and fast twitch
Slow Twitch
- uses oxygen for fuel
- enables continuous muscle use over extended time
- they fire more slowly. but are slow to fatigue
- contain more mitochondria,generate high number of ATP
Fast Twitch
- anaerobic metabolism to create fuel
- they are much better at generating short burst of strength or speed
- contain few mitochondria-less ATP
- fatigue quickly
* an average person has half of slow twitch and half of fast twitch. Olympic sprinters have 80% fast twitch fibers. Marathon runners have 80% slow twitch fibers
Skeletal Muscle
- attached to bones/tendons
- voluntary
- can only pull not push
- aka straited muscles
- work in pairs
- when muscle contracts-transmits tension
- Prime Mover- main group, performs the contraction
- Antogonist-opp.side of joint to prim mover, relaxed when prime mover contracts-reverse movement causes to switch roles
- Synergist-prevents unwanted movements, stabilizes over the joint and controls alternate movements