Hot or Cold, That is the question...

One of the most common questions I hear in my office is "should I use use hot or cold?".
This is a great question, and the answer is...  it depends on what the condition is.  You will often hear ice for 24 hours and then use heat. This generic formula can be a formula for major problems.
First, what do hot and cold do, or what effect do they have on the body:
Hot is works to increase blood flow (a vasodilator) and relaxing muscles.  Ice, on the other hand, slows the flow of blood (a vasoconstrictor) and can cause the muscles to tighten.
Now usually the thing that causes one to wonder "should I use hot or cold", is pain. Then you have to determine what the pain is from, ie, trauma, injury, over exertion, illness... next, look at the other symptoms; swelling, discoloration (redness or bruising), numbness or tingling, nausea, loss of strength, radiating or traveling pain, and, on and on.
When you have injury or trauma, you usually have swelling and inflammation, at least initially.  Inflammation means it's already hot (in-"flame"-ation) so we need to cool things down, use the ice.  Swelling is pooling of blood and fluids as a result of injury, this also is relieved by cold therapy. Also, when you have sharp, stabbing, or radiating pain, you probably have inflammation... use the cold.
Using hot is recommended for muscle spasms and stiffness. Like the kind you get when you fall asleep on the couch with you head on the arm and you can't move your head when you wake up.  Or a sore stiff back from camping over the weekend.  As long as it isn't swollen or radiating, use a short course of moist heat (never dry).
Now what if you pinch a nerve in the back, and it's shooting down your leg, and causes the back to go into spasms?  Always, always, always, start with cold and use only cold until the inflammation is gone or at least dramatically reduced. Then, you may alternate using the hot and cold.
Rules of thumb:
-Ice should never be applied directly to the skin, use a thin towel (like a dish towel) or apply over a tee shirt.
-Ice packs are a better choice for cold therapy than gels for serious inflammation, they will penetrate deeper. Save the gels for night time or going to work.
-20 minutes of cold/ice therapy is long enough.  Too long tightens the muscle, aggravating spasms.
-Heat should be moist, hot towels or hot shower.  Hot tubs can ofter be to hot and over done, 10 min. max.
-Avoid heating pads in general, they can be used too long and are a dry heat.  A moist heating pad can be used if you must, but set a timer!  10-15 min. max, it is easy to over due the heat if there is any inflammation, and you can actually create inflammation if used too long.  Burns can also happen if left on too long, especially when used with a heating agent (ie: Ben-Gay or similar).
-If alternating hot and cold, always start with cold and always allow at least an hour between using one or the other.
-Gels and cream in general are for use as a second resort.
-Remember that icy hot is heating agent, not cold.  Generally will have something like capsaicin or other pepper type elements too make them hot and they can burn if over done.
-Never put a cooling or heat gel, lotion, or oil on and immediately put a hot or cold pack over it, bad reactions and burns can occur.

I could go on, but this gives you the gist of hot and cold.  You them wisely, they are good medicine!
When in doubt, use cold.  It won't get it into trouble, heat will.