Superstar Shah Rukh Khan is so used to working all the time that it becomes difficult for him to stay without doing anything.

"Two days of nothingness and I miss work already. i think my dna is made up of working genes...relaxed loose fit genes don't suit me, " Shah Rukh wrote on micro-blogging site Twitter.

Of late the actor was busy promoting his superhero film "RA.One" and his hard work seems to have paid off as the sci-fi film made at a budget of Rs 150 crore, recovered its costs by earning Rs.170 crore worldwide in the opening weekend despite not so good reviews from critics.