"For me, Covid was worse the second time around and the effects are lasting longer," the 62-year-old wrote in his column in The Sun. "Nine days after a negative test, I am short of breath when I do up my shoelaces and exhausted after climbing a flight of stairs," he said.
WATCH: Did you enjoy series one of Clarkson's Farm?
"Walking the dogs is a real struggle," he continued, before explaining that when he phoned the GP about his ongoing symptoms his doctor queried over his weight, resulting in Jeremy writing: "Staying well is complicated these days, it’s one thing on top of another."
Jeremy spoke about his desire to get fitter in his column in The Times recently, sharing that he'd enlisted the help of a personal trainer, admitting: "None of the shirts in my wardrobe fit any longer [and] I can barely do up my shoelaces," he wrote.
"I've been going for walks every day, but while some of them are seven or eight miles long, I'm not sure they're doing much good," Jeremy said.
Jeremy shared a photo of his positive Covid test on Instagram
"The problem is that I pootle along extremely slowly, and when I get tired, I slow down even more."
The presenter continued that he wasn't convinced by working out with his PT, writing: "People who do this sort of thing for fun say that if you really push your body, you are rewarded with a euphoric high that's better than any drug.
Jeremy Clarkson is trying to get healthier
"I just felt terribly weary," he continued. "And I neither looked nor felt any better than I had done when the session started."
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