My "Hot and Cold Therapy for Pain Treatment after Exercise" introduces what you need to know to treat muscle pain with either a hot or cold therapy.
I also promote that article in "Muscle Pain Treatment with Heat or Cold", which also links to the Canadian Red Cross page for finding a First Aid course near you.
One Therapeutic Writing Tip
The writing tip is that key phrases are just a guide to help you make your article interesting and valuable to your readers.
I started off with an idea about treating sore muscles. That happens to be a popular search item; there must be a lot of people with this problem.
The keyword research might have helped me find an audience; it's far too early to tell. But the Internet did not tell me what topic people seek the most; it does tell me what specific phrases they use when searching.
I still had to think of my topic.
It's a bit like using a thesaurus to find the most popular synonym for the concept that you've already selected.
Pursue your vision, but keep your eyes open for the road signs.