Five Lions players ended up in hospital after the brutal second Test in Pretoria and Robson fears the balance is wrong between power and skill.
"I would have to say this has been the most physical tour, the most physical Test matches I have been involved in," said Robson.
"I think we are reaching a level where the players have got too big for their skill levels.
"I think they have become a little too muscle-bound and too bulky.
"I think you may see changes in the physical nature of the player that brings them back a little - I hope so - in order to speed up the game and introduce a higher level of skill."
The majority of injuries suffered on tour occurred in contact, with the worst being a dislocated shoulder that will keep Wales and Ospreys prop Adam Jones out for up to six months.
Three of the original squad - Tomas O'Leary, Tom Shanklin and Jerry Flannery - failed to make the plane to South Africa because of injury while seven more were ruled out of action before yesterday's third and final Test.
Robson echoed head coach Ian McGeechan in urging the home nations to find a way of giving the Lions the best possible chance of success in four years' time.
From a medical perspective, that is additional time before the tour begins which can be invaluable for keeping players fit.
"We started with the proposition nobody would come on tour that was unfit. I hope that is the way forward," said Robson.
"I hope that in the future the Lions will get a little more lead-in time because the time we had for preparation with the players - and the data we collected - allowed us to develop programmes of rehabilitation and hopefully that helps us to keep players on tour for longer."