LUKE CALDWELL has admitted the 2015 campaign is make or break for his chances of making the grade as a full-time athlete after swapping the high life of New Mexico for west London and a sideline teaching kids about Newton's Laws.

The 23-year-old Scot returns to action in tomorrow's Great Edinburgh International XC for the first time since coming 40th at last month's European cross-country championship in his biggest test since returning from the USA and switching his coaching regime.

Now guided by Nic Bideau, who nurtured Andy Vernon to two European medals on the track last summer, the Oxford graduate has put his physics degree to use in providing A-Level tutoring in a bid to finance his quest to explore just where his true potential lies. Abandoning the life of a lab boffin, and his prior research into super-conductors, has been a necessary sacrifice.

"I do miss the cutting edge stuff a bit," Caldwell admitted. "I've weaned myself off it slowly. I had a little bit of leftover work when I left New Mexico, so I've not gone completely cold turkey. But I might not now need something, just to keep it all ticking over. But I want to put myself in a position where I'm doing everything I can to get better at running and see what happens."

Vernon, his daily colleague during sessions at Twickenham's St. Mary's University, has served to inspire after finding belated success at the age of 28. If nothing else, it has taught Caldwell that patience can be a virtue even if the returns do not immediately come.

"It would be nice," he declares. "He'll tell me it's not the case I'm sure. But I'd just like to run better on the track over 5000 and 10,000m than I have before, and also get some experience in trying to break into teams but being at the trials and getting qualification times in. It's going to be tough to get to the world championships. But that's the kind of target I have to set."

Much, including Edinburgh, is trial and error. Soon, Caldwell will head indoors to get a better feel of where his strengths and weaknesses lie. Longer-distances on the road will also offer attractions, despite a tough initiation at the Great North Run where the boon of coming sixth on his half-marathon debut was offset by the physical pain.

"The Great North was a disaster," he said. "I was quite ill and I'm not sure now how much the run told me. From ten miles onwards, it was a write-off, so I didn't get to explore how m body reacted to going beyond the limits I'd had before. But doing one of those huge races, with crowds the whole way, going up against world-class athletes, was great. I'd like to do something like that again."