Adding to what LaRue and Daniel have said,
Something else that may be of help would be to study the material in different locations. I have a minor in Psychology, and I can actually apply that knowledge here!
I learned in my Cognitive Psychology class that when you attend a class (lecture) it’s best to sit in the same spot every time, and sit there when you take your test because that’s where you learned most of the information. This way, you have every possible cue for memory recall, which helps you on the exam.
The ACSM exam will not offer this luxury, so it would be best to learn the material in a variety of places. You could even go so far as to use the “method of loci.” In short what you do is take a chunk of knowledge and relate it to a location that is meaningful to you. Say for instance, your house represents a certain collection of facts. You break it down by parts of the house and learn to associate certain facts with certain parts of a house. You can add up the parts of your house (facts or knowlege bits) into a big picture that makes sense to you.
In theory, you can learn a certain set of facts “here”, walk through that location (literally) and recall those facts, then walk through that location (figuratively) in your mind, recalling those facts as you take your mental journey through the location. It helps with recall because it allows you to better use your working memory (specifically your visuospatial sketchpad (seeing it in your head) and your phonological-articulatory loop (talking to yourself in your head).)
Might be worth a shot…
I think the real key to permanently learning anything is integrating the information into your life. The method of loci makes it easier for some people to do just that.