What can you do to reverse the effects of sitting down all day?

Those of you familiar with the TV series Mad Men may have been bemused at the practices that went on in office environments in the 1960’s-1970.
It wasn’t just Don Draper’s good looks that were smouldering - entire offices were often cloaked in a fog of cigarette smoke as smoking wasn’t the health pariah it is now. It is somewhat ironic then that long after smoking was prohibited in the workplace, health care experts are dubbing sitting down the new smoking.