MP’s should not have second jobs

I might understand it if Messer’s Rifkind and Straw took holiday jobs like many of us subordinates do especially as MPs have generous, extended holidays but taking on a second job when they are supposed to be representing their constituents is outrageous. Surely an MP’s job is not only full time but also exhausting taking the incumbent into the dead of night and often early rising. Even if there comes a lax period it must be incumbent on the MP to walk into the constituency and talk with people to find what their problems are and discuss solutions.