I tried to explain to the wife how intervals are good for you. You run 1/2 mile at 6.30 min pace then jog for 1 min at 11 min pace repeat for 8 or 9 times and then jog slowly for 10 mins to cool down, all this is preceded by a 10 min jog to warm up, this would be a hard session, for me anyway. She looked at me with a patronising smile, only wives can do this, and said "I don't have a clue what you are talking about" turned round and carried on with the weeding.
Now I just tell her I will be out for an hour, " hours or whatever. They just don't understand the fine art that is training.