Trevor Bayne says he is looking forward to his racing return, although he still does not know exactly what caused the symptoms that have kept him from racing for the past five weeks.
The 20-year-old American spoke for the first time since missing a NASCAR Nationwide Series race and was enthusiastic at feeling "100 per cent" ahead of his planned return to action at Chicagoland next weekend.
Bayne said that his symptoms were probably the result of an isolated event, which may be related to an insect bite that sent him to hospital for the first time in early April.
"I think I finally just had to accept that nobody knows," said Bayne when asked about what his illness was. "I can promise that if I was just tired or not feeling great I would have still been in the race car because I am a racer. I went to bed on the Monday night feeling great and woke up Tuesday and I was seeing two of stuff and that wasn't cool.
"I went to the hospital and had the best doctors in the world at the Mayo Clinic checking me out and they don't know. That is all it is. I have had to accept that... Everything is pretty much 100 per cent back to normal and that is pretty exciting.
"The symptoms were double vision; there was inflammation which was temporary obviously because all of my symptoms have gone away. The cause isn't exactly sure yet. Their biggest hope is that it was an isolated event that is temporary and is gone now.
"The diagnosis... I don't have it yet. I don't know. It could be just a series of events where you get a bug bite and your immune system is down and we had been running for a couple months hard every day after Daytona and it wears down your immune system.
"That is what I am hoping for. Whether that is it or not, only time will tell with that."
Bayne is hopeful that his symptoms have completely subsided after testing for the past two weeks and getting back to his training routine. He said any kind of terminal diseases were ruled out by doctors at the Mayo Clinic, where he underwent several tests while there was some suspicion about Lyme Disease being his illness initially.
"There is always a concern that you had it once and never expected it," added Bayne. "They just said to make sure I am hydrated all the time, which I probably wasn't doing the best job at that. Michael McDowell always says that hydration is the key to life, joking around with me, but now it really is.
"I just need to make sure that I am cautious and rest and stay hydrated and that is the best I can do. I've got to get back to working out. I have been on a bike for a couple hours at a time every day for the last week at the highest heart rate, 160 or 170 [bpm], and nothing has shown any symptoms again.
"Hopefully it was an isolated scenario where a lot of things were going on and my immune system was down and you get a bite, and anything can send it into a spiral."
The Daytona 500 winner is upbeat about his racing return with Roush Fenway Racing in NASCAR's second-tier series. In three weeks' time he will also race for the Wood Brothers again, driving the #21 car at the Michigan Sprint Cup race.
"I am pumped about that. I have raced at Chicago twice so far, once in a Waltrip car and once in a Roush Car and have a little experience there but not a tonne," added Bayne. "I am excited about that but I am really excited about Michigan and getting back in both series and riding in Ford's back door and that could be a good weekend for us.
"We were really fast there last year in the Diamond Waltrip car and the Roush cars were really strong as well. I am looking forward to the experience I got last year carrying over to this year and it being a good experience for us."
Bayne is watching from the sidelines this weekend at Charlotte, where he had been initially scheduled to race. His Nationwide car will be driven by Matt Kenseth while his Cup machine will be raced by Ricky Stenhouse Jr, who will be making his debut in NASCAR's top series after winning in Nationwide for the first time at Iowa last week.