Android : Android, regarding the best implementation to not overload the database

I am trying to send some values that are Incrementing/Decrementing through 2 buttons and write them in the Database.I don't know the best solution to not overload the mysql.I made some researches and I have read that is not good to use CountdownTimer or timer because there might be problems canceling and starting again.I wanted to use a Thread but I can't update application UI from a thread that is running in background if I am right.I made something like this and I couldn't use Log to display when thread finished.Also I found a place where it said that I can use a Runnable ( I don't have experience with Runnable and I don't know how to use it ) Thank you and looking forward your answers !