When I see an error on a blog or website, I can’t be certain whether the problem is a misspelling or a misunderstanding. (Sometimes, the incorrect spelling of the intended word is the correct spelling of a different word.)
When a word that is out of place (i.e., the meaning of the sentence doesn’t make sense) sounds or looks a lot like another word that would make sense, in context, the improperly used word is called a malaprop (or malapropism).
Malaprops can be humorous—but they can also be embarrassing (especially when they are unintentional).
Refute means to deny or reject. Thus, the sentence is saying the exercise under discussion is not a valuable tool. (I don’t think this is the meaning the writer intended.)
What might have this writer intended?
Reputed is an adjective meaning something is widely known or believed and assumed (think “reputation”). Example:
The city is reputed to be the filthiest in Europe.
If something has been reported, it has been discussed or mentioned but not confirmed or verified.
The exercise is reported to be a valuable tool for maintaining good health.
Rewriting unclear sentences (and paragraphs) may require changing more than one word. For the above excerpt, stating the source of the information might be helpful.
My teacher, Ahara Lamb, showed me an exercise that is designed to . . .
Or, an indication that the assertion is hearsay or an opinion might be warranted.
I’ve heard reports from those who practice this exercise that it can help alleviate . . .
In my opinion, this is one of the best exercises for . . .
In my experience, this exercise is important for . . .
If you are uncertain about the meaning of a word, look it up in a dictionary or find examples of correct usage. (The Internet makes this step quick and easy!)
To be effective, communication must be clear (at a minimum!). Don’t allow carelessness (or laziness) to undermine your efforts.