Monday 29 June at 15:59 : Jun.29 (GMM) David Coulthard believes he might have quit formula one at least a season too soon

The Scot, 38, contested nearly 250 races over 17 seasons, before retiring at the end of 2008

But despite the success of his successor Sebastian Vettel, Coulthard told Scotland's Daily Record that he thinks he could have handled the pace of 2009

"In such a high-pressure sport you have to be able to recover and come back and deliver each time. I questioned whether I still had the energy to do that," he said

However, this year's regulations are demanding less of the drivers: for example, in previous years a three-week calendar gap would have meant incessant on-track running, but the class of 2009 is instead enjoying an extended holiday at present due to the total ban on in-season testing

"As it happens, the way the regulations changed I almost certainly would have had the energy to handle a season," said Coulthard

But the winner of 13 grands prix insists he does not regret hanging up his helmet before he was physically incapable of being a top race driver

"I felt that Red Bull had good alternatives and that it would be better to recognise ahead of time than recognise after or be the last to know it was time to go," he said

Coulthard now travels to every race as an expert pundit for British television, and he admits to enjoying witnessing first-hand the fruits of his four years in the Red Bull cockpit since the team's inception

"There are middle grid teams that stay in the middle grid but along with other people I helped influence the positive development of Red Bull and they've gone forward and progressed each year," said Coulthard, now a consultant to the Milton-Keynes based outfit