My boyfriend definitely does not have diabetes or RH. Out of interest, I take his BG from time to time. Whether he has eaten recently or not it is almost alway 5.2.
He often partakes in intensive cycle rides for more than an hour.
Recently, I decided to take his BG before and after cycling.
Before it was his usual 5.2. After it was 3.9.
He had a shower and was back to his usual 5.2.
This is only a small sample but it shows you are not alone.