No. Top them off before storing them. Top them off every couple of weeks if you won't be using them.
Here's my cycle of batteries.
The day of a race I will use the Tekin tray that discharges each cell. Then charge the batteries full. Run a race. Top them off again. Then I use that battery for the third qual. or the main. A different battery is used for other qualifiers, but it gets the same treatment. When I get home I top off the batteries again and wait till next weekend. A minimum of two Nimh's is needed for a day of racing for one vehicle. Unfortunately I have two vehicles and I require lots of practice so I have 8 packs that get used during one race day.