The Muscular System

Question 1

functions of the muscular system

Answer 1

-allows movement
-helps circulation of blood
-protects and keeps our abdominal organs in place
-good posture
-generate body heat when they contract

Question 2

muscles are divided into 3 groups:

Answer 2

1. voluntary muscles
   eg. biceps and triceps
   -only move when we make them
   -make up majority of muscles in the body
   -used in everyday & sporting activities
2. involuntary muscles
   eg. bowel and intestine
   -work automatically and not under our control
3. cardiac muscle
   eg. the heart
   -works consistently and automatically, only found in the heart

Question 3

antagonistic pairs
the biceps and triceps

Answer 3

in the upper arm - these work together to bend (flex) and straighten (extend) the elbow joint
this is what happens during a press up, bicep curl or tricep dip

Question 4

antagonistic pairs
the quadriceps and hamstrings

Answer 4

in the leg - when the quadriceps contract, the hamstrings relax and the leg straightens
this is what happens during a leg press or squat

Question 5

antagonistic pairs
the gastrocnemius and tibias anterior

Answer 5

in the leg - the first acts to plantar-flex the ankle, while the second acts to dorsi-flex it
this is what happens during hurdling, or when you do a reverse calf raise

Question 6

antagonistic pairs
the hip flexors and gluteals

Answer 6

work to flex the leg at the hip (hip flexors contract and gluteals relax)
pulling the leg back at the hip to kick a football (hip flexors relax and gluteals contract)

Question 7

agonistic

Answer 7

the muscle that contracts to cause movement

Question 8

antagonistic

Answer 8

the muscle that relaxes to allow movement

Question 9

fast & slow twitch muscle fibres

Answer 9

• type 1
• type 2a
• type 2x

Question 10

muscle fibres:
type 1

Answer 10

-slow twitch muscle fibres
-used for low intensity work as they can be used for a long time without tiring (rg. the marathon)

Question 11

muscle fibres:
type 2a

Answer 11

-fast twitch muscle fibres
-used in anaerobic work
-can be improved through endurance training to increase their resistance to fatigue (eg. the 400m)

Question 12

muscle fibres:
type 2x

Answer 12

-fast twitch muscle fibres
-used for anaerobic work
-can produce much greater force than other fibre types
-they tire very quickly (eg. 100m sprint, shot-put)

Question 13

myoglobin

Answer 13

red pigment that transports oxygen to the muscles

Question 14

aerobic

Answer 14

oxygen work

Question 15

anaerobic

Answer 15

no oxygen work

Question 16

there are two types of muscle contraction:

Answer 16

-isometric
-isotonic

Question 17

isometric

Answer 17

-during this, there is no change in the length of the muscle, so no movement takes place.
-it is just an increase in tension (eg. handstand, plank) no movement but the muscle is still working

Question 18

isotonic

Answer 18

-during this the muscle will change length so therefore movement will happen (eg. throwing a netball)

Question 19

long term effects of physical activity on the muscular system

Answer 19

-increase strength
-increase endurance
-increase power
-firmer, more toned body
-stronger tendons and ligaments
-better posture

Question 20

hypertrophy

Answer 20

the increase in muscle size

Question 21

progressive overload

Answer 21

damages the muscle fibres, so they grown back and repair themselves stronger