The active ingredients in BenGay, Icy Hot, and Mentholatum Deep Heat are methyl salicylate & menthol-topical. Some other topical creams contain capsaicin.
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“These medications are able to stimulate a part of the nervous system that sends information into the spine about a sensation (such as a warm or cold feeling) that is usually not painful. For example, if someone is suffering from a muscle ache, these products may send signals into the spine about a cooling sensation. When this signal is combined with the signal of pain from the sore muscle, both signals enter the spinal cord at the same area. However, the brain may be able to only read so much signal at a time and may average the two signals and thereby decrease the pain. These preparations attempt to crowd out the pain signal, thereby decreasing the pain by altering the combination of signals in the spinal cord.
Although this may sound like complicated medical and physiologic phenomena, we actually learn about our nervous system’s pain message center at a young age. This is quite intuitive, because for most of us, when we bump our shoulder or injure another part of our body, our natural tendency is to rub that area. This reaction is much more than “kissing the boo-boo.” Essentially, when we rub an area that has been injured we are doing the same thing as placing Ben-Gay, Icy Hot or other type of counter-irritant on the injury. We are offering the central nervous system another stimulation, or a sensation that is not perceived as painful. Therefore, these products attempt to “crowd out” or augment the painful messages that are coming into the spinal cord from the injured area.”
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For science-minded PEers, the book, “Therapeutic Heat and Cold”, by Justus Lehmann is worth reading.
It looks like carefully regulated ultrasound would be the ultimate heating method.
Started: 2/03, Finished: 5/06, Total Gains: 1.375” BPEL 1.5” EG, Details: Progress after a year or longer off?
Only those who attempt the absurd will achieve the impossible—M. C. Escher