Nervous System

                 Peripheral                         Central

        Somatic       Autonomic                 Brain/Spinal Cord

              Sympathetic   Parasympathetic

• CNS (central nervous system)

1. Medulla oblongata
2. Pons
3. Mid-Brain
4. Cerebeullum
5. Diencephalon
6. Telencephalon

• PNS (Peripheral Nervous System)
• everything else
• 12 cranial nerves
• 31 spinal nerves

CNS

• Afferent
• Efferent
• Interneurons

Neurotransmitters

(brain/spinal cord)

The spinal cord contains 3 types of nerves:

• Sensory
• motor
• Interneurons

Chemical messengers

• Epinephrine
• Norepinephrine
• Serotonin
• Dopamine
• Acetylcholine

Peripheral NS

• Somatic & autonomic
• Sypathetic & parasympathetic

• Voluntary muscle- skeletal muscle & skin
• Involuntary muscle- visera & other tissues

• Supplies heart, smooth muscle, sweat glands, viscera
• Supplies thorax, abdomen, pelvis regions

• Most organs receive sympathetic & parasympathetic stimulation

Reflex Arc

• Simple Refles
• Comples Refles
• Learned Reflex

• Sensory nerve ->spinal cord ->motor nerve ->muscle

• Same as simple, but multiple synapses & muscle groups

• Little conscious effort because of something you do frequently (ex: advanced typists don't think about typing each letter, it is reflex)

• One motor neuron & the specific muscle fiber it innervates
• Muscle fibers & nerve that activates them

• All or none principle

• Gradation force

Motor Neuron (Motoneuron)

• dendrites
• body & axon
• myelin sheath
• schwann cells
• Nodes of Ranvier

The anterior motor neuron

• cell body
• axon
• dendrites

• Schwann cells
• Myelin sheath- lipoprotein membrane that wraps around the axon
• Nodes of Ranvier
• Gaps every 1-2 minutes
• Allow AP to jump

Neuromuscular Junction

• Presynaptic terminals (membrane)
• Sacrcolemma
• Synaptic Gutter
• Synaptic Cleft

(or motor endplate)

• Represents the interface between the end of a motor neuron and a muscle fiber
• Anatomic features of a neuromuscular junction:

1. Presynaptic membrane
2. Synaptic Cleft
3. Synaptic Gutter
4. Postsynaptic membrane

Neuromuscluar junction

Excitation

• Action potential travels down axon & acetylcholine is accumulated in synaptic vesticles
• Ach is released from presynaptic terminal/membrane into synaptic cleft/gutter
• Ach bins to postsynaptic membrane & ion channels are opened
• Sodium is pumped into sarcolemma & the electric stimulus is converted to a chemical stimulus
• Action potential is formed that travels along sarcolemma into t-tubule system
• Sarcoplasmic Reticulum (SR) is stiumulated & calcium (Ca+) released
• Muscle fibers contracts

Neuromuscluar junction

Excitation

(continued)

• AP stimulates the sac-like 'synaptic vesticles' at the NMJ to release Ach
• Ach binds to a receptor on the postsynaptic membrane (Electric Stimulus converted to chemical stimulus)
• Sodium- potassium pump (Na+ - K+ pump)
• The AP (wave of depolarization) travels the length of the sarcolemma entering the T-tubule system
• Stimulation of SR releases Ca+

Neuromusclular Junction

Facilitation

• Excitation threshold
• remporal summation- time/timing, how often excitation takes place
• spatial summation- how many fibers activated in excitation 

Effective dishibition (not stopping/letting happen)- fully activated all muscles during maximal lifting

Neuromuscluar Junction

Inhibition

• Presynaptic terimals release chemicals increasing post synaptic membranes permeability to charged potassium (+) or chloride ions (-) inhibiting depolarization (stimulation)

• Protective function that inhibits depolarization (stops firing of muscle fibers) & reduced input of unwatned stimuli

• IIx- fast twitch: high tension, high force, fast fatigue
• IIa- hybrid/fat twitch: moderate tension, moderate force, fatigue resistant
• I- slow twitch: low tension, very fatigue resistant

Motor Unit

• All or none principle
• Gradation of force principle

• All fibers in a motor unit are activated or none of them are

• Force of contraction depends on

1. Number of motor neurons recruited
2. Frequency of motor unit discharge

Motor Unit

Recruitment

• Size principle

Process adding motor units to increase muscle force

• Motor neurons with smaller axons (I) are recruited first. If demand is there than neurons with larger axons (IIx & IIa) are activated. Type I is first on and last off

Motor Unit

Neuromuscular Fatigability

The decine in muscle tension capacity repeated stimulation is caused by:

• Exercise induced alterations in levels of CNS neurotransmitters
• Glycogen depletion
• Hypoxia (not enough oxygen)
• Interruption of AP at NMJ

Proprioceptors

Muscle Spindles

• Stretch reflex

Receptors that monitor information about a movement

• Stretch reflex: causes muscles to contract
• Provide information to fiber length & tension
• Allow for adjustments in muscle tension or force

Proprioceptors

GTO's

• Tendon Reflex

Golgi Tendon Organs

• Tendon reflex: cause muscles to relax
• Located in musclotendious junction
• Detect difference in tension (rather than length) generated by active muscle
• Protect muscle from excessive load (Tendon Reflex)
• Respond to tension generated by
1. Muscle contraction
2. Passive Stretch

1. Skeletal
2. Cardiac
3. Smooth

Gross Structure of Muscle

• Endomysium
• Perimysium
• Epimysium
• Sarcolemma
• Sacroplasm Reticulum (SR)

• Wraps each fiber
• Surrounds several fibers & forms bundles called Fasciculi
• Surround all the bundles to form the entire muscle
• Under Endomysium- muscle cell membrane
• The fiber's aqueous protoplasm, contains sarcoplasmic reticulum (network of tubular channels)
• Releases Ca+ - necessary for muscle contraction

Gross Structure of Muscle

• Chemical Composition
• Water
• Protein
• Salts
• Blood Supply
• Rish vascular network
• Blood flow
• Rhythmic vs. sustained contractions

Muscle is about

• 75% water
• 20% protein
• 5% salts, phosphates, ions, & macronutrients

Rich vascular network; rhythmic contactions helps blood flow, sustained contraction hurts blood flow

• During sustained contractions > 60% capacity blood flow diminishes due to intramuscular pressure
• Anaerobic processes supply ATP
• Vessels compress during contraction & open during relaxation

Gross Structure of Muscle

Capillarization & impacts by aerobic/endurance training

Aerobic/endurance training creates increased capillary density up to 40%

Endurance exercise training & capillarization

• Expedites removal of metabolic by-products
• Increases 02 delivery

Ultrastucture of Skeletal Muscle

Sacromere

• I band
• A band
• H zone
• Z line

(at rest vs. during concentric contraction)

From Z line to Z line

• actin (thin/light)
• myosin (thick/dark)
• myosin, disappears during contaction
• stabilizes structure; bisects I band & adheres to sarcolemma

Ultrastructure of Skeletal Muscle

Actin-Myosin Orientation

• Crossbridges- lollipop like or similar to canoe paddles
• Troponin
• Tropomyosin

Actin filaments lie in a hexagonal pattern around myosin

• Spiral around the myosin where actin & myosin overlap. Crossbridges on myosin pull actin across it
• Modifies Troponin to block binding site. Embedded at regular intervals along actin
• interacts with Ca2+
• moves tropomyosin, revealing cross-bridge binding sites
• Complex on actin that contains binding sites. Lies along actin in the groove formed by double helix
• Covers cross-bridge binding site

Ultrastructure of Skeletal Muscle

Intracellular Tubule System

• T-Tubules
• Triad

The sarcoplasmic reticulum is distributed around the myofibrils such that each sarcomere has 2 triads

• System of tubes runs throughout muscle
• Pattern of SR. T-tubule, SR
• Each triad contains
• 2 vesticles- terminal end of SR that stores Ca++
• 1 t-tubule

Chemical & Mechanical Events during Contraction & Relaxation

• Sliding Filament theory

• Contraction occurs in sarcomere as myosin & actin slide past each other
• Ca+ is released from SR & troponin unblocks tropomyosin
• Myosin cross-bridges cyclically attach, rotate, & detach from actin filaments
• Energy provided by ATP hydrolysis

Link between

Actin

Myosin

ATP

• Myosin crossbridges binds to actin at one site; the binding of ATP at second site on the crossbridge causes the crossbridge to release & "cock" in preperation for power stroke
• Splitting of ATp (via myosin ATPase) creates the release "cocking" and power stroke
• Cylce begins again when another ATP binds to myosin
• Repeated nonsynchronous power strokes continue as long as a stimulus is present

Excitation

• Contraction coupling

The process by which the muscle membrane action potential leads to the release of intracellular calcium from SR, thereby causing muscle contraction via the sliding filament theory (basically connecting #4 & #10 together because Excitation cause Sliding Filament Theory

• Calcium is actively pumped back into SR
• Troponin allows tropomyosin to interfere with actin-myosin interaction
• Cessation (stopping) of nerve stiumlation
• Oreventing mechanical link between actin & myosin inhibiting myosin ATPase activity

Muscle Fiber Types

• ST (Type I)

Slow twitch

• Low myosin ATPase activity
• Slower calcium release & re-uptake by SR
• Low glycolytic capacity
• Large number of mitochondria

Muscle Fiber Types

• Ft (Type II)

fast twitch (IIx & IIa)

• High capacity to transit AP
• High myosin ATPase activity
• Rapid release & re-uptake of calcium by SR
• High rate of crossbridge turnover
• Capable of high force generation
• Relies on anaerobic metabolism (ATP-PCr/Glycolosis)

Muscle Fiber Types

• Type IIx (FG)
• Type IIa (FOG)
• Type IIc

• Most rapid shortening velocity
• Rely on anaerobic energy production
• Fast shortening speed, moderately well-developed capacity for both aerobic & anaerobic energy production
• Rare & undifferentiated (reinnervation)

• Large individual difference in fiber type distribution
• Endurance atheltes have more Type I fibers
• Same as high as 90-95% in gastrocnemius
• Speed & power athletes have more Type II fibers
• Middle distance athletes, throwers/jumpers/ & high jumpers have more even fiber distribution

3 Energy Systems

• Times & examples

• ATP-PCr- immediate enery
• 10 seconds (sprint, weightlifting)

• Glycolytic- splits glucose to form ATP
• 60-90 seconds (endurance, anerobic power)
• ATP-PCr + Latic Acid
• Oxidative (Aerobic)
• Over 2-3 minutes (cycling, jogging, swimming)
• ETS & Krebs

General Training Principles

• Overload
• Specificity
• Individual Differences
• Reversibility

• Exercising at greater than normal intensity
• Performing a specific activity increases your ability to perform that ability (if you want to run a long distance train aerobically)
• Specificty of VO2max
• Specificity of local changes
• SAID prinicple
• Everyone is different & responds differently to physical activity
• Detraining; Rapidly losing abilities/capabilityes after cessation of an activity or exercise

Adapatins to Training

Responders & Nonresponders

Physcial capabilities are partly genetic (twin study)

• Exercise Adherance
• Less than 13% of US adults exercise regularly at sufficient intensity & duration to attain minimum fitness levels
• Drop out rates mimic other behavior-oriented programs (eg smoking, alcohol, weight loss)
• Proper leadership exerts the greatest positive influence on exercise complience

Anaerobic System Changes

• Increased leveles of anaerobic substates (ATP, PCr, free creatine, glycogen, glycolytic enzymes)
• Increased quantity & activity of key enzymes that control the anaerobic phase of glucose catabolism
• Increased capacity to generate high levels of blood lactate during all out exercise
• Increased capacity to generate LA during intense exercise (Buffering?)

Aerobic System Changes

• Metabolic Adaptations

• Number & size of mitochondria
• Oxidative enzymes
• Ability to oxidize intramuscular triglycerides
• Muscle fiber size & type
• Oxygen extraction capabilities
• Ability to oxidize carbohydrate

• Cardiac hypertrophy: the "athletes heart" eccentric & concentric hypertrophy
• Heart size (up)
• stroke volume (up)
• oxygen extraction (up)
• plasma volume (up)
• improved blood flow & distribution
• heart rate (down)
• blood pressure (down)
• cardiac output

Pulmonary Adaptations

• max exercise
• submax exercise

• Increases minute ventilation

• Reduces ventilatory equivalent
• Tidal volume increases as frequency decreases

• Decreased rate of formation
• Increased clearence rate
• Greater tolerence to lactate acumulation (OBLA)

Everday 45-60 minutes

• increased lean mass
• decreased fat mass

• Body regulates, transports, & sheds heat more effectively

• mood is better
• release of endorphins

Factors Affecting Aerobic Training Response

• Goals of Aerobic Training 
• Initial level of Cardiorespiratory fitness (can't find)

• Develop functional capacity of the central circulation to deliver oxygen
• Enhance aerobic capacity of the specific muscles (to consume oxygen)

• Calories expended per unit of time
• Train at a perception of effort (RPE)
• Train at lactate threshold
• METs
• Train at percentage of VO2max
• 50-60% of VO2max lower limit; 85-90% upper limit
• Train at a percentage of HRmax
• 60-70% HRmax to get a training effort, 90% upper limit
• Heart Rate Reserve- Karvonen Method
• lower limit of 50% HRR, upper limit 85% of HRR

• 40 year old male- working between 50%, 60%, & 85% of HRR; RHR is 75 bpm
• 220-40 = 180 EMHR - 75 RHR= 105 HRR

     105                     105                   105 bpm

  x .50                    x .60                  x .85 bpm

     52.5                     63                      89.3 bpm

  + 75                     +75                    +75 bpm

    127.5 bpm           138 bpm             164.3 bpm THRR

• 5- year old man working between 60 & 80% of HRmax
• HRmax -> 208 - (.7 x 50) = 208 - 35 =173 bpm

      173              173

    x  .60           x  .80

    103.8           138.4 bpm THRR

Training Duratin

Training Frequency

Trainability & Genes

• Varies inversely with intensity, at least 30 minutes each session

• At least 3 times for at least 6 weeks

• Closely linkes
• Responses to training are very dependent upon genetics. Responder vs. non-responder

• Exercise intensity plays a principle role in maintaining the increase in max aerobic power achieved through training
• with intensity held constant, frequencey & duration to maintin aerobic fitness is considerably lower than required for improvement
• Small declines in intensity reduces VO2max
• Duration & intensity can be decreased as long as intensity is maintained

• Slowly decreasing exercise to prepare for competition
• Allows muscle to resynthesize glycogen to max levels
• Allows healing of training included damage

Formulating an aerobic training program

General Guideline

• Start slowly, warm up, cool down period

• More than 60 minutes a day (serveral hours for elementary children)
• Periods of 15+ minutes of moderate to vigorous activity
• Children are not small adults
• Participate in variety of physical activity
• Extended periods of physical activity are not appropriate for normal healthy children
• Cardiorespiratory fitness standards for children
• 1 mile walk/run

Establishing Training Intensity

• percent of VO2max
• percent of MHR
• RPE
• Lactate threshold (couldn't find)

• 50% to 55% VO2max
• 70% HRmax
• Effectiveness of less intense exercise
• 6 very very very light to 19 very very hard
• Rate of perceived exertion

Methods of Training

• Anaerobic
• Aerobic

• The intramuscular high energy phosphates & lactate generating capacity

• Continuous (LSD) training
• Interval training
• Fartlek training (speed play)

Overtraining Syndrome

• symptoms

Unexplained/persistent poor performance/delayed recovery

• symptoms (persist unless there is rest)
• Prolonged recovery from exercise bouts
• Disturbed mood states- fatigue, depression, irritability
• Insomnia
• Weight loss, loss of appetite
• Elevated RHR, painful muscles, susceptibility to upper respiratory infections & gastrointestinal disturbances
• Overuse injuries

Overtraining Syndrome

• Symptoms

Unexplained/persistant poor performance/delayed recovery

• Symptoms (persist unless there is rest)
• Prolonged mood states- fatigue, depression, irritatbility
• Insomnia
• Elevated RHR, painful muscles, susceptibility to upper respiratory infections & gastrointestinal disturbances
• Overuse injuries

Effects on the fetus

• Reduces placental blood flow
• Fetal hypothermia
• Reduced fetal glucose supply

• Pregnancy induced hypertension
• Preterm rupture of memebranes
• Incompetent cervix
• Type 1 diabetes
• Excessive alcohol intake
• Multiple prenancy
• History of premature labor
• Intrauterine growth retardation
• History of two or more spontaneous abortions
• Persistant second to third trimester bleeding
• Preterm labor during the prior or current pregnancy
• Smoking
• Anemia
• Excessive obesity

What act requires that the plaintiff must show that the jobs are substantially equal in order

 to prove that they have been treated unfairly?

 What act prohibits the denial of benefits to older workers?

Age discrimination and employment act

What act makes it illegal for employees to do things absed on about race, gender, and national origin?

What act allows victims of paid discriminiation to assert with their rights?

Must consider

• Nature and cost of the accomodation
• What financial resources that they have
• The overall finacial resources of the facility involved in the provision of reasonable accommodation
• The number of persons employed at such a facility
• The effect on expenses and resources
• The impact otherwise of such accommodation upon the operation
  

of the facility

• Federal Funding
•  Educational program
  
• Gender discrimination

• žQuid pro quo
• žTangible employment actions
• žHostile environment

Tangible employment actions

• firing
• failing to promote
• reassignment

Three-step approach:

Sexual Harassment

How to prove/defend

What has to be present

What is it

What does it include

Unwelcome sexual advances, requests for sexual favors, and other verbal or physical conduct of a sexual nature constitute sexual harassment when

• Submission to such conduct is made either explicitly or implicitly a term or condition of an individual's employment
• Submission to or rejection of such conduct by an individual is used as the basis for employment decisions affecting such individual
• Conduc has the purpose/effect of unreasonably interfering with an individual's work performance or creates intimidating, hostile/offensive work environment

Difficult to discern:

• The disincition between invited, uninvited-but-welcome
• Offensive-but-tolerated
• Flatly rejected sexual advances

Examine:

• Nature of conduct
• Context in which it occurred
• Frequency of conduct
• Severity
• Physical threatening/humiliating
• Unwelcome
• Interference with work performance

• žThe private interest that will be affected by the official action
• žThe risk of an erroneous deprivation of such interest through the procedures used, and the probable values, if any of the additional or substitute procedural safeguards.
• žThe government’s interest, including the function involved and the fiscal and administrative burdens that the additional or substitute procedural requirement would entail

Due Process

• Eligibility
• Process
• Aspects

• To produce, through the use of fair procedures, more accurate results (not depriving people of their rights)
• To provide a feeling of fair treatment by the govt. among people

The government must:

1. Provide notice of the charges against you.

2.  Be able to show that there is a non-vague standard of conduct which you are accused of violating.

3.  Provide you with an opportunity to rebut their charges against you in a meaningful way and at a meaningful time  (the "hearing requirement“)

 4. Establish-at a minimum--that there is substantial and credible evidence supporting its charges. 

5.  Provide some explanation to the individual for the basis of any adverse finding.

Due Process

• Substantive
• Procedural

Substantive

• žSubstantive due process requires the rule or regulation to be fair and reasonable in application as well as content.
• žIn the absence of fraud, mistake, collusion or arbitrariness, the courts generally will not interfere with the internal affairs of voluntary associations.

The inquiry in substantive due process asks 2 questions:

Procedural

• žExamines decision-making process followed in determining whether a rule/regulation was violated and what sanction should be imposed.
• žFair treatment is the goal
• žThe greater the right/interest being deprived, the greater procedural due process that is owed to the plaintiff.

What are you going to considering when determining if a person is eligible to get due process in the first place

The starting point is state action

•Is their state action?

The constitution limits the government conduct, not private conduct

• Is the government's role in the conduct sufficent enough to be deemed "state action"?
  
• Can cover many persons who have only an indirect relationship with the government
• Controversial area
• DeShaney v. Winnebago County (1989)

An institution effectively accommodates students if it meets one of the following:

• žUnlawful to discriminate on the basis of race, color religion, gender or national origin in any employment activity.
• žIllegal for employers to refuse to hire or deprive individuals their status as an employee due to these classifications

• žProhibits employers from discriminating on the basis of sex between employees at the same establishment who perform equal work in equivalent positions under similar working conditions
• žSkill = experience, training, education, ability
• žEffort = amt. of phys./ment. Exertion to perform job
• žResponsibility = degree of accountability required

To succeed under the EPA, must Show:

There is no EPA violation if the reason for the unequal pay is due to:

• —A seniority system
• —A merit system
• —A system that measures earnings by quality or quantity of production
• —Any other factor based on something other than sex