Help with lookup function

Help me (and presumably others) interpret your score sheets. It's easy to tell apart the sections that refer to gender, but it's not clear (at least not to me) how the column and row headers refer to age....so if you could walk through in English (i.e., in words) what you would do if doing this identification of, say, minimum sit up score for male at age 21. What's the range of numbers there, how would they be identified (visually, in words) from which the minimum is to be selected? I know it's clear to you, and maybe it's something obvious that I'm missing. I suspect the formula will be fairly straightforward, but I need to know how to navigate that array of numbers.