Lecture 3 (heat) Flashcards
What are the 3 kinds of heat therapy?
Moist hot pack
Parafinn
Fluidotherapy
What is thermal conductivity?
How well heat flows through matter
What is heat?
The speed at which particles are moving
How well heat flows is based on 3 things. What are they?
Intensity of heat applied
Time of exposure to heat
**What is being heated **(sticking hand in oven at 212 degrees is a lot different than a bowl of water at 212 degrees) - this is because water is much more conductive than air is –> water will transfer its heat at a much quicker rate than air will and a solid will transfer heat even faster (depending on the solid)
KNOW:
Things that transmit heat from slowest to faster
Air –> Water –> Sold (depends on solid [metal = faster])
Kinetic motion of atoms / molecules of one object is passed on to another object
Hot object comes into contact w/ another hot object is called
Conduction
What two heat modalities utilize conduction?
Moist hot pack, parafin
Object transmits heat directly to skin
KNOW: w/ conduction the easiest way to remember it is sold coming into contact w/ sold or still object coming into contact w/ still object
* think sticking hand into non-moving water. this would be conduction (still object w/ solid object) because nothing is moving
* The other key to conduction is that the objects must be in direct contact
Bulk movement of moving molecules in lquid or gases is called
Convection (remember that theres movement w/ this)
Convexion = bulk movement of moving molecules in lquid or gases
when it gets hot somewhere those molecules take that heat and move elsewhere
think blood flow throughout the body w/ EX
* say were doing grip isometrics = increased heat in that area –> increased blood in that area and heated w/ conduction then the blood moves (heat moving) = convexion (moving heat) and heat is dispursed throughout the body
EX in a nonpainful area causes the painful area to heat up (which is what we want). Is this conduction or convexion?
Its convexion because those heat molecules are being dispursed around the body
NOTE: if pt comes in w/ a back issue and we want to heat it up it would be beneficial to put them on a bike to do this because were getting that theraputic EX while heating the messed up area (bad part is when pt comes in and depends heat pack)
KNOW: this is more effective for heating the body than just putting a hot pack on (conduction) because this is multiple tissues heating up and dispursing throughout the body.
What is the conversion of heat energy to electromagnetic radiation?
Radiation
Do all objects emit / absorb radiation?
Yes - unless they’re absolute zero
Does ice amit radiation?
Yes, any object above absolute zero. However, it doesnt admit that much
Do we use radiation in PT?
No
KNOW: Convexion is moving fluid particles
If I’m trying to heat the entire body could I use a hot pack? If not what would be ideal to use?
No - isnt big enough
Use THEREX
Does muscle return to baseline quickly after heated / cooled? Why or why not?
Will not because of high water content
Why is muscle tissue able to absorb and hold onto heat better?
Increased water content
* note it also does this with cold
Why does fat take longer to heat up than muscle?
Because it has less water content
What holds onto heat / cold longer muscle or fat?
fat because it has bad bloodflow
KNOW: Muscle has loads of blood flow
What temperature is therapeutic?
104-113
Anything under this is normal body temp
At what temperature does tissue damage occur?
above 122
Does heat increase or decrease elasticity?
Increases it (get more flexible / less ridgid when warm)
Does heat increase or decrease viscosity?
Decrease (makes it less thick) (think snow in tubes melting or something boiling becoming les thick)
Does heat increase or decrease joint stiffness
decrease (stifness decreased by heat)
Does heat increase or decrease muscle flexibility
Increase
Will heating a contracture help it?
NO!!! heat effects are not physiologic
Does adding heat change you actaul muscle phsyiology
No!!
Why does heat help to loosen you up / make you more flexible
It helps your brain relax your protective muscle tone (more psycological) DOES NOT psyologically affect your sacromere length!!!
Does adding heat increase sarcomere length?
Nope
Does heat increase or decrease pain?
It depends but it can sometimes help
* on the whole we do use it for pain reduction except under some circumstances
(cold will also decrease pain due to not being able to sense it as much)
KNOW: one way heat helps w/ pain is if the pain is coming from stiffness it will help release the muscle and cause a relief
However, if their pain is for something like fracture or infection it will not help pain (infact it will facilitiate the mechanism of that pain due to increased BF)
Does heat cause vasodilation or vasoconstriction
vasodilation ( = more BF)
* that muscle relaxiation (release of that protective tone) also goes to that smooth muscle in our blood vessels causing them to relax and dilate
* It also causes hormones to be released into the blood causing vasodilatoin
* permability is also increase (tissues can get more stuff into them)
Does heat increase or decrease cell actvity? is it good or bad
Increase
Its good and bad
If were trying to increase some kind of chronic issue we can send more heat there and increase cell activity
* however, we wouldnt want to do this to areas that are already healing properly (we don’t need an excess of blood to an area that already has an appropriate healing response [think an acute fracture w/ lots of swelling])
* However, if the healing process just isnt happening then i might want to - helps restart that healing process
However, we wouldnt want to increase cell activity in a cancer