It means it just has to be
within a three day window I believe. So that is within 72 hours of when your plane leaves. If you got tested 4 days before the flight left they would not accept it at the airport. You can get tested anytime within that 72 hours but make sure the lab can get you a copy of the results back in time before you leave to the airport. At the Sportsman's lodge they gave me a print out which I like. I do not trust having it on the phone to show them in case my phone malfunctions at the airport.
I am really glad I went. Staying at the lodge makes you feel like Hugh Hefner for 5 or 6 nights.
IN the USA you can be an average dude that most attractive women ignore but in the lodge you just show up and act reasonable and polite with the Ticas and you are all set. I already new a Tica from before. If I am meeting new ones I just by them a drink to see if they seem to have a reasonable personality. If they are really pushy I don't take them to my room. When I have hooked up with a pushy one I have always regretted it. The ones I have enjoyed the most let the men come to them.