The 16-year-old powered to two victories in as many at the Caen BMX Indoor International during the last weekend of February – his first major race of the season.
Cullen triumphed in the Under-16 Boys and the Open race, where anyone from the ages of 13 to 16 can take part.
And the Preston Pirates BMX Club star says his fast start to the new season is down to the hard work he put in over the winter break.
“I always set a target to podium at as many races as I can, and obviously I was going to France confident of getting a good start to the season, and that’s what I got,” said Cullen, who benefits from being on the SSE Next Generation programme.
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“It was a positive start – it was the first big race of the season.
“Once I ride those guys again at European races or other races, it gives me the upper hand. I know I’ve beaten them recently and they’re thinking, ‘He’s quick’, so mentally it gives you a good start.
“It shows that the training I did over Christmas with British Cycling has been really successful, and I’m getting something out of the hard work I’m putting in.”
Cullen is an ambitious racer, and with good reason since he is a two-time junior BMX racing champion.
However, he has never won the European crown and that is something he is itching to put right in his final year before he moves up an age group to the juniors.
“The first European round is in Zolder in Belgium at the start of April – I want to podium there and have a really successful weekend,” he added.
“Throughout the year I want to hopefully get back the world title.
“And I’ve never won the European Championships, that’s the only title that I haven’t won, so I want to dig deep and go for that this year, especially as it’s my last year before I go up the junior age group.
“I’d like to make it a successful season. I’ve just joined a new team in BVC Bikes – they’re a Belgian team, and they’ve done so much for me already.
“I hope all these things pay off and I can get my title back.”
SSE’s Next Generation programme partners with SportsAid to provide financial support and training to the sports stars of the future. Keep up to date with the latest @SSENextGen