Graham Norton has said his new Virgin Radio show will be a "jolt in the arm" after a decade on BBC Radio 2.
The presenter, who makes his debut as a weekend host on Saturday, joked that it was the first time he had had adrenaline in his body since 2010.
The 57-year-old is following in the footsteps of ex-Radio 2 DJ Chris Evans in joining the station, and is being replaced at the BBC bypresenter Claudia Winkleman.
He told the PA news agency: "I would say I am kind of nervous. Nervous and excited, which are both rare for me. I like it. I like feeling like this.
"I haven't had adrenaline in my body for about 10 years. It is quite a shock to the system."
Speaking about feeling grateful for the job during the coronavirus pandemic, he added: "I am genuinely excited because the opportunity of starting something new at this time is amazing.
Norton broadcast his final Radio 2 programme from London's Wogan House in December - 10 years after his first Saturday morning show for the station.
He will be joined at Virgin Radio by long-standing presenting partner Maria McErlane, who is known for co-hosting the Grill Graham agony aunt segment.
But Norton predicted his debut would be "a bit weird".
He said: "There are bound to be a few suits sniffing around and I will be aware that there are probably going to be some journalists listening to it to see what I say... oh God.
"Sunday will be the proper first day where it will just be me and the real listeners and we will just have a nice time. But tomorrow will be a bit odd I imagine."
Norton also appeared on Evans' breakfast show on Friday, where he admitted he kept forgetting he had doubled his weekend workload.
"Even I keep forgetting about the Sunday show," he said.
"I hope I show up. I was in the supermarket yesterday looking at avocados thinking, 'Oh, that would be nice on Sunday morn... oh, no'."
However, the chat show host said the additional programme would not affect him too much due to Covid-19 restrictions already halting his social life.
Evans, 54, also reminded him of the role he had played in prompting his move away from the BBC.
He said: "The last time you were on the breakfast show you said, 'It's lovely here', and I said, 'It is, it is'.
"And you said, 'You seem so different and happy', and I said, 'I know'.
"I loved working at Radio 2 but I didn't realise there was another level of joy to be had. And you got the same vibe, didn't you?"
Norton replied: "I really did. And you were saying, 'Oh you should come and work here'. And as I left thinking, 'Well, that will never happen, but actually that would be quite nice'."
Norton joined Radio 2 in 2010 to host the 10am to 1pm slot on Saturdays, taking over from Jonathan Ross.
Figures released in September showed he was among the top earners at the broadcaster and that he took about £725,000 for his Radio 2 show and some TV work, but not his BBC One chat show.
- Graham Norton is on Virgin Radio on Saturdays and Sundays from 9.30 to 12.30.