Study Session 3/12/19

Study Session: 3/12/19

Muscle Anatomy:

Actin: Skinny he's just act'n

Myosin: Muscle bound guy

Sliding filament theory: Proteins in the muscles, actin and myosin form a connection to pull the thin actin filaments over the myosin (In essence the skinny guy is pulled forward on the muscle bound guy)

A-band: Area of the sarcomere does not shorten during contractions
I-band: Area between the thick myosin filaments in which only Actin is found
Z-band: Separates sarcomeres
H-zone: found between the actin filaments in which only thick myosin is found



Smallest component of the muscle is the Sarcomere which is a contractile unit found in striated muscle that is bound end of end and shortens upon muscular contractions.

Sarcomeres are connected end to end to form to create a myofibril.

Muscle contraction: Calcium ions are discharged from the sarcoplasmic reticulum into the sarcomeres, this results in a release of troponin and tropomyosin which exposes the actin filament for crossbridging from the myosin heads.

Once done contracting, the relaxation phase causes the calcium ions to return to the sarcoplasmic reticulum.

Recharge phase: Allows for replenishment of ATP to maintain muscle action spectrum.

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Force-couple: Concomitant contraction of various muscle groups that produce movement of the body. Essentially they contract together to get a desired movement.

Length-tension relationship: Optimal muscular length at the level of the sarcomere for maximal force potential of the muscle. I.E. desk workers with rounded shoulders, the cross bridges are not optimal to respond well to outside stimulus.

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Hypertrophy: Two types

Sarcoplasmic: Sarcoplasmic reticulum and muscle glycogen stores are increased, doesn't mean stronger though

Myofibrillar:Increased size of muscle fibers and results in improved cross-sectional area, leading to increased strength

Hyperplasia refers to an increase in the number of muscle fibers, but is not well understood

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Cardiovascular system:

Pericardia: Outermost layers of the heart, contain a lubrication liquid
Epicardium: Layer of tissue outside the heart a deep part of the pericardia
Endocardium: Inntermost smooth layer of the heart walls.

Pulmonary system:
Mouth -> Trachea -> Bronchi ->Bronchioles -> Alveoli

Red Blood Cells (RBC) contain Hemoglobin which carries oxygen to the tissues

Platelets: Clotting factors

Pathologies:
Sinus node - arrhythmias
Blood pressure - systolic / diastolic, checked while seated on the right arm
* Hypertension is indicated as greater than 140/80 (needs physician clearance)
* Hypotension is indicated as less than 90/60 (needs physician clearance)
Atherosclerosis: hardening/narrowing of arteries due to plaque deposits (needs physician clearance)
Asthma: inflammation of the respiratory airways
COPD: chronic obstruction, difficult to exhale, tidal volume chronically high

Effects of Exercise: Typical
Hyperventilation: Body needs more air to create more ATP
Systolic blood pressure rises, but diastolic should not
Cardiac output: Increases
Long term effects:
Improved heart efficiency, increase heart size, increased capillary density, decreased BP, increased blood volume, increased cardiac output

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Nervous System:

Autonomic nervous system: Controls involuntary actions that occur in the body such as respiration, heartbeat, digestive processes, etc.
* Sympathetic: "Rest and digest"
* Parasympathetic: "Fight or flight"

Somatic nervous system: Body's ability to control skeletal muscle and voluntary movement as well as the involuntary reflexes associated with skeletal muscles.

Pathologies:

Epilepsy: episodic seizures due to disruption of the CNS
Alzheimer's disease: Loss of memory and deteriorating cognitive function, due to degeneration of neurons in the brain. (usually 60+, trouble retaining newly acquired information)
Multiple Sclerosis: Gradual breakdown and scarring of the myelin sheaths surrounding axons due to immune system attacks in a neuron; often causes vision trouble, difficulty walking, fatigue, pain, involuntary spasms, etc.

Effects of exercise on the NS: Increased efficiency of nerves
* New clients see improvements stemming from increased efficiency allowing them to lift more with less effort (not hypertrophy)

Pattern of nerve conduction:
Impulse travels to motor unit, acetylcholine released into synaptic cleft, received by sarcolemma, action potential triggered, calcium released which allows for cross bridging to occur

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Endocrine System:

Glands: regulate processes throughout the body with secretion of hormones.
Hormones: Control metabolic processes, growth and development, sexual reproduction, etc.
Hypothalamus: Control of autonomic nervous system function, and connection between the body's CNS and the endocrine system.
Pituitary: Regulates human growth and development
Pineal: Regulates release of melatonin
Parathyroid: Responsible for the regulation of the body's calcium levels
Adrenal glands: Produces epinephrine, norepinephrine, cortisol and aldosterone, Catecholamines
* Epinephrine: Controls heart rate, BP, etc.
* Cortisol: Regulates stress processes like blood sugar, macronutrient metabolism etc.
* Catecholamines: Assist in muscle output and improve energy stores and rate of contraction
Pancreas: regulates insulin

Two catagories of hormones
Anabolic: Growth and development (Testosterone, Estrogen, Insulin, Insulin-like growth factor (IGF)
* IGF - Synthesized in the liver and aids in the tissue growth and many other functions, maintain and repair muscle
* Anabolic steroids: Causes reproductive organ function declines, psychological side effects, and severe damage to the liver
Catabolic

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Digestive System:

Mouth: Saliva assists in the first process to break down food
Esophagus: Mouth to stomach
Somach: Acidic bolus aka chyme breaks down food
Small intestine: Significant nutrient absorption takes place here
Large intestine: Larger in diameter to assist further in nutrient absorption, water absorption, and waste collection and production of feces
Sphincters throughout digestive system: Upper/Lower esophageal, Pyloric,  Ileocecal, and Anal

Bile: Neutralizes chyme, created by liver and stored in the gallbladder
Pancrease aids in the production of enzymes for digestion, insulin

Largest portion of nutrient absorption takes place in the small intestine, (exception alcohol in stomach)
Breakdown generally occurs in the mouth and stomach

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Strength and Power Formulas

Mass: Amount of matter than any particular object is made up of (measured in kg)
Force: Mass of an object x its acceleration
Acceleration: rate of increase in velocity
Velocity: Rate at which an object is traveling including its direction and magnitude
* Also: Rate at which an object travels a specific distance

Newton's Laws:
1: Objects in motion remain in motion until acted on by outside forces
2: Mass of the object determines the amount of force required for acceleration
* Force = Mass x Acceleration
3: When an action occurs their are equal and opposite reactions

Work: Force x Distance
Power: Work/Time
Momentum: Mass x Velocity
Impulse: Force x Time
Rotational Work: Amount of force needed to move an object through an angular range of motion
Rotational Power: Work / Rate at which they are applied (time)
Angular velocity: Rate at which a muscle produces movement through the full ROM at a joint

Strength: Ability to apply force to an object, no time component, it is simply the all-out effort from the muscle.

Force-velocity curve: As force of the muscle increases the velocity will decrease (think of a bicep curl; the more weight required the more force required, but that slows down the velocity)

Force-time curve: time it takes to reach peak force output by the muscles, as time increases the amount of force is more and more limited.

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Bioenergetics: Term used to describe process by which the body converts energy for difference uses

ATP:Adenosine Triphosphate - The basic unit energy required by the body to perform movement, etc.

Metabolism: Chemical reactions that build and break down tissues in the body
* Anabolism: Build up molecules
* Catabolism: Break down or burn larger molecules into smaller ones

Two major energy systems for exercise
Aerobic system: Ability of the human body to covert macronutrients into ATP in the presence of oxygen for sustained duration.
Anaerobic system: Ability of the body to produce ATP via creatinine phosphate or muscle glycogen stores found in the body

Krebs cycle / Electron transport chain: ATP creation process
Aerobic metabolic breakdown of macronutrients by mitochondria to form CO2 and ATP
Glycolysis creates a coenzyme called acetyl coenzyme A (acetyl CoA) used in the Krebs cycle
- Refers to the ability of the body to break down blood glucose and muscle glycogen stores to create ATP
Glycogen: glucose based energy supply synthesized and stored in the liver and skeletal muscle

Acetyl CoA: Produces
* 2 molecules of ATP - Fuel the body
* 4 molecules of CO2 - Expired through lungs
* 6 molecules of NADH - Sent through Electronic transport chain to produce additional ATP
- NADH niacin based coenzyme vital in electron transfer
* 2 molecules of FADH2 - Sent through ETC to produce additional ATP

Electronic transport chain: portion of Aerobic metabolic process in which NADH and FADH2 are used to transfer hydrogen ions to oxygen, forming water and releasing energy in the form of ADP. ADP is then converted to ATP

The electronic transport chain can produce an additional 34 ATP as a result of the Kreb cycle metabolizing acetyl CoA. (Also aerobic)

Anaerobic production of ATP is another method to create energy
Creatine phosphate is used to synthesize ATP rapidly during the first seconds of exercise.
- The phosphate group in creatine phosphate supplies ADP with the additional phosphate to create ATP and supply more energy for movement.
The phosphagen system takes advantage of this to produce ATP for high intensity exercise at short durations of less than 10 seconds.
Bouts of intense exercise at this intensity for longer periods tend to create byproducts that hinder performance such as lactic acid.
- lactic acid builds up in the bloodstream when oxygen demands are not met. The pH of the blood in the muscles cause intense burning sensation that limits performance.
- Lactate threshold refers to the maximal rate at which lactic acid can be buffered from the bloodstream.
Training can allow for the raising of the lactate threshold and are able to withstand higher instensities for longer periods.

Training can also improve an individual's oxygen uptake, the ability of the body to consume and utilize oxygen
Oxygen deficit: necessitation of anaerobic processes to supply energy needs at the start of an exercise session until the oxygen uptake reaches a steady state
Oxygen debt: excessive consumption of oxygen to return the body to a resting state.
Excess post-exercise oxygen consumption (EPOC): similar to oxygen debt and refers to the body's continued consumption of oxygen following exercise for a full return to homeostasis
- Results in increased energy expenditure after exercise (great for weight loss)