What is air saturated with when it is inhaled?

What temperature is it warmed to?

The volume of air that reaches the alveoli per minute.

V_A= (V_T × F_R) - (V_D ×F_R)

1. Abdominal contents push up against diaphragm.
2. There is an increase in intrapulmonary blood volume in the horizontal position.

1. Don't consider the chest size of the individual.
2. Would be better to use sitting height rather then standing height.

no problem with the airways but there is damage to the lung tissue - loss of elasticity and compliance - limited expansion of the lung - pulmonary fibrosis, pneumonia.

Lung tissue becomes stiff and unable to expand very far.

a) atrial - tachycardia

b) nodal - second and third degree heart blocks

c) ventricular - premature ventricular contraction (PVC), ventricular tachycardia, ventricular fibrillation

a) pressure difference between left ventricle and right atrium

b) skeletal muscle pump                                           

c) Respiratory pump- during inspiration                     

1. Alveolar-capillary

2. Tissue-capillary  

VO2 = HR × SV × (a-VO2)diff

HR = heart rate

SV= stroke volume

(a-VO2)diff= arterial-venous oxygen difference

1. The ability to ventilate the lungs and oxygenate the blood passing through the lungs.

2. the ability of the heart to pump the blood

4. the ability of the working muscles to accept a large blood supply

5. the ability of muscles to extract oxygen from the capillary blood and use it to produce energy

1. THe test should exceed 6 mins but less then 15 mins

2. incorporate a warm up period in the first stage of the test

3. the test protocol should be arranged in stages, with each stage progressively increasing in intensity untill the termination criteria is reached.

1. The oxygen consumption ceases to increase linearly with increasing work rate and approaches a plateau

2. Heart rate should be close to age predicted max (220-age)

3. Blood lactate levels should be * millimoles/liter or greater, 3-5 minutes post exercise.

4. Respiratory exchange ratio (VCO_2/VO₂) should be greater then 1.10

5. Subject should look exhausted

1. Less expensive

2. portable

3. Dont require electricity

4. patient is more stable 9 easier to collect data, eg. HR BP)

5. Easier to quantify work rate

1. Cant abtain as high a VO₂ max.

2. Cycling is not as a common movemnt for most individuals as compared to walking

1. Less expensive

2. Tests can be submaximal - saftey

3. Some tests can be administered to large groups

4. less motivation is required from the individual (subject)

1. Linear relation between heart rate and oxygen uptake

2. Similar maximum heart rate for all subjects

3. In cases where vo2 is predicted from work rate, machanical efficiency is assumed

4. Day to day variations in heart rate

1. Forbrain

i)Cerebrum- cerebral cortex, basal nuclei

ii) Diencephalon - thalamus, hypothalamus

2. Cerebellum

3. Brainstem - medulla, pons, midbrain

1. Afferent division

2. Efferent division

1. Somatic nervous system

2. Autonomic nervous system

 i) Sympathetic division

 ii) Parasympathetic division

Neurons are nerve cells that are specialized to transmit electrical signals.

It consists of

1)Cell body (stoma)

2) Axon

3) dendrites

4) Myelin sheath

5) shwann cells

1. Afferent neurons

2. Efferent neurons

3. Interneurons

1. Resting potential - high [Na] outside causing the nerve to be electrically negative

2. Action potential - stimulus causes Na ions to flow into the nerve cell causing a reversal of polarity

1. Cervical enlargement which extends from C4 to T1

2. Lumbosacral enlargement which extends from T11 to L1

ischemia,

1. fractures
2. dislocations
3. atherosclerosis

1. Tonic stretch

2. phasic stretch

3. gamma system

gamma efferent fibers innervate the contractile ends of the intrafusal fibers. when the alpha motor neurons are activated, the gamma motor neurons are activated (coactivation)

Gamma system provides the mechanism for maintaining the spindle at peak operation at all muscle lengths.

the firing rate of the GTO is very sensitive to the changes in the tension of the muscle

1. Sensory input is important for a variety of motor acts, such as mainting a steady grip on an object

2. when stimulated by excessive tension or stretch it sends information to the CNS causing the contracted muscle to relax (reflex inhibition) 

- the purpose of this is to protect the muscle and its connective tissue harness from damage due to excessive loads 

instead of synapsing directly with motor neurons, this pathway involves many of the other brain regions, including the cerebellum. These pathways are more concerned with posture and coordination of large muscle groups.

Considerable complex interaction and overlapping of function exist between these two systems

by means of intricate feedback circuits to monitor and coordinate other areas of the brain involved in motor control.

It recieves signals concerning motor output from the cortex and sensory information from receptors in muscles, tendons, joints and skin, as well as from visual, auditory and vestibular end organs.

1. production of a fast output of high quality.

2. an appearance of ease and smoothness of movement.

3. an anticipation of variations in the stimulus situation before they arrive.

4. Reduction in time to make a choice of responses once the signal is identified

1. Input variables

2. state of the performer

3. nature of the practice afforded

1. Based on precision of movement

2. Based on the distinctiveness of beginning and end points of the movement

3. based on stability of enviornment in which the skill is performed

1. Gross motor skills- involve large musculature as the primary basis for movement

2. Fine motor skills- skills the require the abilty to control small muscles of the body in order to achieve the successful execution of the skill

1. discrete motor skill- clearly defined begining and end point. these can be put together to form serial motor skills

2. continuous motor skills- have arbitrary beginning and end points.

1. closed skills- the performance environment is stable

2. open skills- the performance environment is constantly changing

1. cognitive state

2. Associative stage

3. Autonomous stage

1. to guide error correction

2. to reinforce correct performance

3. motivate the individual toward achieving a performance goal.

1. positive transfer

2. negative transfer

3. zero transfer

4. bilateral transfer- one hand helps the other

1. Pressure effects- when breathing through a snorkel, the diver must inspire air at atmospheric pressure.

2. Increase in pulmonary dead space

diver inflates lungs and begins to ascend. as rising the partial presser in the lungs decreases and from boyles law the volume of gas increasing causing:

1. alveoli to rupture.

2. air bubbles to enter blood vessels blocking arteries in heart or brain causing heat attack or stroke.

at depths over 100ft, the increased partial pressure and quantity of dissolved nitrogen produces an anesthetic effect on the central nervous system.

The effects are simmilar to alcohol (ie. decreased awareness to cold, hallucinations, decreased attentiveness, reckless behaviour)

when inspired PO₂ exceeds 1520 mmHg for longer than 30-60mins

can cause: irritation of respiratory passages which pregress to pneumonia

a small membrane lined passage connecting the middle ear cavity and the back of the throat.

equilibrate the pressure within the ear cavity with the outside by transfering air to or from the lungs

1. Radiation

2. Conduction

3. Convection

4. Evaporation

1. Increase in metabolic rate

a) voluntary- exercise

b) involuntary- shivering

2. Increased tissue insulation - vasoconstriction of peripheral blood vessels and shunting of blood flow into deeper vessels.

1. skinfold thickness

2. Gender

3. clothing

1. Immersion in cold water or wet clothing

2. wind

3. Physical exhaustion

4. Inadequate clothing for conditions

5. low percent body fat

6. hypoglycemia

7. alcohol consumption - causes a decrease in shivering, increase blood flow to skin, impairs judgment

1. decreased oxygen content in arterial blood.

2. decrease in maximal cardiac output due to a decrease in maximum heart rate and stroke volume. Decreased stroke volume decreased by reduction of venous return volume because of decreased blood volume.

a) since VO2 max is decreased a higher percentage of VO2 max is needed

b) there is reduce blood buffering because of the loss of bicarbonate ions

The number of days needed to acclimatize depends on the altitude:

9000ft->

12000ft->

15000ft-> 

7-10 days

15-21 days

21-25 days

a) increased hemoglobin concentration

b) local muscle adaptations - in creased number of mitochondria, oxidative enzymes

1) decreased maximum stroke volume

2) increased V_E at a given workload

2) decreased buffering capacity of blood for lactic acid

1. staged ascent - ones reaching 8,000 ft you should not increase by more then 1000 ft/day.

2. avoid alcohol

3. High carb diet

4. appropriate exercise level

5. Take certain drugs (Diamox)

6. fluid ingestion

7. keep in mind that different people acclimatize at different rates

1. Retinal hemorrhage above 17500 ft

2. hypothermia, frostbite, sunburn

1. Improvement of sports skill technique

2. Design of sports equipment

3. prevention of injuries

4. Clinical analysis of movement pathologies

5. Design of prostheses

6. Design of rehabilitation devices

force distributed over a given area. Units= N/cm²

P= F/A

1. get someone to help

2. Stand facing the object feet flat pointing straight and shoulder wisth apart

3. Face the object in the direction you intend to move it (avoid twisting)

4. Keep the object as close to you as possible

5. get a good grip

6. bend at knees and hip keeping back straight

7. lift using knee and hip extensor muscles

8. carry object close to your center of gravity

1. the point of intersection of the three cardinal planes of the body ;frontal, transverse and sagittal

2. the point of exact center, around which the body can rotate

3. the point around which the weight is equal on all opposite sides

1. Used to describe the movement of the body through space.

2. Important for stability

3. It is important factor in calculation of amount of work done

1. reactions board method - used for a static position of the body. Assume that the center of gravity is the fulcrum or balance point and then apply the Principle of Levers.

2. Segmental method - can be used for finding CG of a body in motion

1. Increasing body mass

2. Increasing the size of the base of support in the direction of the line of action of an external force

3. Vertically positioning the CG as low as possible

4. Increasing friction between the body and the surface contacted

5. Horizontally positioning the CG near the edge of the base of support towards the oncoming external force

1. Law of inertia

2. law of acceleration

3. Law of reaction

work = force times distance

units= 1.0nm = 1.0 J (joule)

Power = ?

units?

power = work per unit time = Fd/Δt = force times velocity

units = watts - 1 watt = 1 J/sec.

1. in running there is a period when both feet are off the ground. Consider running as a series of jumps.

2. In running, there is no period where both feet are on the ground at the same time.

3. In running, the stance phase is much smaller in proportion of the total gait cycle than in walking

first class- fulcrum in the middle (lifting rock with plank of wood)

second class- resistance between fulcrum and force (wheel barrow)

third class- force between fulcrum and resistance ( arm)