How often will you switch the value of your units after a big win????

lets say you start with 5 grand using a max bet of 40$, min. bet of 5$ 1-8 spread. get some good cards and double your money and now have 10 grand. do proffesionalls then double the thier unit size to 10$, 80$ max. or do they just keep playing wiht the same betting spread and unit size????
thanks