Romo was forced to undergo surgery on his back in December, raising questions over whether he would be able to fully recover considering his advancing years.
However, the 34-year-old took part in limited training during the organised team activities today and is on course to return to full fitness in time for the beginning of training camp in July.
"You start off with a certain number of throws you're going to do," Romo told reporters.
"A certain number of reps, and then you take it a little bit more and a little bit more and you make sure your body keeps getting comfortable. Been going with that progression here for a while so it's been good."
Romo threw for 3,828 yards and 31 touchdowns during the 2013 campaign.