Sports Science B.1.1 - B.1.4 Flashcards
superior
Towards the head
Inferior
Towards to floor
Proximal
Closer to the trunk of the body
Distant
Further from the trunk of the body
Medial
toward the midline
Lateral
Away from the midline
Anterior
Towards the front of the body
Posterior
Towards the back of the body
Superficial
Towards the surface of the body
Deep
Going deeper into the body
What is the Axial Skeleton and its function
The inner parts of the skeleton. Rib cage skull Vertebrae sternum. It is for protection attachment movement and support
What is the Appendicular skeleton and its function
The outer skeleton - ex. pelvic griddle, arm bones, leg bones, shoulder bones etc. For attachment movement support, and blood cell formation
Sagittal plane
Divides the body into right and left
Frontal Plane
Divides body into front and back
Horizontal plane
Divides body into upper and lower
Adduction
Moving a body part towards the midline (upwards)
Abduction
Moving a body part away from the midline (downards)
Retraction
Moving a part backwards
Protraction
Moving a part forward
Bone
Provides support for the body and facilitates movement
Tendons
Connects muscles to the bone
Ligaments
Connects bone to other bones
Cartilage
Shock absorber for the body
Fascia
Reduces friction and provides support
Fibrous Joint
Connected by fibrous tissue.
No movement permitted.
Ex. sutures in the skull.
Cartilaginous Joints
Connected by cartilage.
Limited movement.
Ex. intervertebral discs (in the spine)
Synovial Joints
Surrounded by a joint capsule.
Filled with synovial fluid.
Allow a wide range of movements.
Ex. the knee and shoulder joints.
Function of all joints are
Movement, Support and stability, and shock absorption, weight distribution, organ protection, smooth movements (no friction)
What is a motor unit
Functional Units of Muscle contraction that has motor neurons and the muscle fibers it controls.
Whats in the middle for a first-class lever
Fulcrum in the middle then relatively same length load and effort
Whats in the middle for a second-class lever
Load in the middle with a large effort arm smaller load arm
Whats in the middle for a third-class lever
Effort in the middle with a large load arm and small effort arm the fulcrums at the very end
Example of a first class lever
The neck when nodding (head resting on the spine). The joint acts as the fulcrum, the muscles at the back of the neck provide the force (applied force), and the weight of the head is the resistance. They are rare in the body.
Ex of second class lever
The calf muscles and Achilles tendon during plantarflexion (e.g., standing on tiptoes). The ball of the foot acts as the fulcrum, the calf muscles apply force, and the body weight provides the resistance.
layups, high jump etc
Ex of a third class lever
The biceps brachii during elbow flexion. The elbow joint acts as the fulcrum, the biceps muscle applies force, and the weight in your hand is the resistance.
Most levers in the body are third class and have evolved to favour range and speed of motion Or swining a tennis racket in sports
When is there a mechanical advantage?
a mechanical advantage when the effort arm is longer than the load arm
When is there a mechanical disadvantage?
mechanical disadvantage when the effort arm is shorter than the load arm.
Calculation for mechanical advantage
effort/load
In the body what is the effort?
Your muscles are the effort. They provide the power and strength to move Ex. throwing a baseball your arm muscles does the effort to throw the ball
Whats the load in real life scenarios?
Whatever your lifting ex. baseball, dumbel etc
In the body what is the fulcrum
In the case of throwing a baseball, it would be the shoulder joint in general its what doesn’t move and just stays the same.
What is a motor unit?
A functional Unit of Muscle Contraction
What does a motor unit have in it?
A motor neuron and muscle fibers
What does a motor unit do?
Carries information from the central nervous system to muscles to tell them to either relax or to contract.
What constitutes as a motor unit?
When One motor neuron connects to multiple muscle fibers which is called a Motor Unit
Dendrites
Extensions that receive signals from other neurons. They look like fingers, or branches
Cell Body
Receives signals from the dendrites also contain nucleus
Nucleus
In the center of the cell body, it holds the DNA
Axon
Extends from the cell to the motor end plates. Covered in myelin sheath which increases signal rate.
Motor end plate
Where neurons meet muscle fibers
cardiac muscle
Involuntary, striated muscle
Smooth Muscle
Involuntary, and non-striated can be found in internal organs like intestines.
Skeletal muscle
Attached to the bones, Voluntary, Heavily striated, we decide when to produce movement using skeletal muscles
What does ATP consist of and whats its function
ATP is the main energy currency in the body. It consists of three phosphate groups attached to an adenosine unit. The last phosphate breaks off the ATP to release energy in a catabolic reaction.
What is the all or none priciple?
when a motor neuron sends a signal (action potential) to a muscle fiber, the muscle fiber contracts fully or not at all.
If it doesn’t reach the threshold it won’t contract at all if it does reach the threshold no matter how high it will contract at the same power.
Type 1 fibers
They have a smaller diameter and don’t get tired easily at all.
Involved in activities that require endurance, like long-distance running or triathlons, marathons, and maintaining posture.
They are rich in mitochondria and myoglobin, which help their fatigue resistance and carrying lots of oxygen, and make them red.
Type IIa fibers
These fibers are the middle in size and in general between Type I and Type IIx fibers.
Type IIa fibers have a moderate resistance to fatigue and are involved in activities that require both strength and endurance.
They contain a mix of oxidative and glycolytic enzymes and are light pink in color.
Type IIx fibers
They have a larger diameter and generate more force but fatigue more quickly.
Type IIx fibers are involved in activities that require short bursts of power, such as sprinting or weightlifting.
They rely heavily on anaerobic metabolism and have fewer mitochondria and less myoglobin so they are white in colour.
Hypertrophy
Muscle growth when you work out or exercise muscle the muscle fibers increase.
Atrophy
Muscle wasting/decrease - Atrophy is the decrease in muscle size and can result from disuse, injury, or certain medical conditions. Muscle fibers can be wasted (not used much) or complete unused
Isometric Contraction
Contraction without the muscle changing length ex. planking, wall sits
Isotonic Contraction
Muscle contraction is where there is a change to the length of the muscle. (there are two types)
Concentric Contraction
The muscle shortens
This is typically associated with the lifting phase like in a bicep curl the come up os concentric the muscle shortens as its lifting.
Eccentric Contraction
the muscle lengthens while still under tension.
This occurs during the lowering phase of an exercise when the muscle is controlling the movement Like the tricep in the come down of a bicep curl, or hamstring in going down in an RDL.
Isokinetic Contraction
involves a constant speed of muscle movement. usually achieved with specialized equipment that provides resistance through a full range of motion at a constant speed.
less common in everyday activities but are used in certain rehab and strength training settings.
Reciprocal Inhibition
ensures smooth and coordinated movement by sending signals to the antagonist to relax when the agonist is contracting. so both muscles don’t contract at the same time and interfere with each other’s actions. So it prevents injury and helps movements go smoothly.
Agonist
It contracts concentrically (shortens) to generate the force needed for the action.
For example, during a bicep curl, the biceps brachii is the agonist responsible for flexing the elbow.
Antagonist
The antagonist is the muscle that opposes the action of the agonist.
It typically relaxes or lengthens to allow the movement to occur smoothly.
In the bicep curl example, the triceps brachii acts as the antagonist because it lengthens while the biceps contract.
