Hill-climbs are pretty straightforward: you ride up a hill as fast as you can on as light a bike as possible.

But the aftermath can often be gruesome, with riders falling off their bikes into grass verges, vomiting and occasionally passing out. The effort and toll is sometimes too much.

For Adam Kenway, one of the favourites for this year’s National Hill-Climb Championships on Bank Road in Matlock, 2015’s Nationals proved to be a ride with consequences.

The Metaltek-Kuota rider had a sickness bug a fortnight before the race on Jackson Bridge but felt well enough to train for the Riber and Bank Road double-header, the week before the Nationals.

But after riding Riber first, he “got to the top and I was physically sick. Sometimes I feel sick, but I’ve never before actually been sick,” he told CyclingWeekly.

“I did Bank Road in the afternoon and had an awful race; I felt empty. The next two days I had this sickness bug again, the week before the Nationals. Looking back on it I should have called it quits then.

“But in the end, I thought it’s only a couple of minute effort, if I just sit up and recover I’ll be fine. I was tapering from that point anyway and wasn’t putting any efforts in.”

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His refusal to withdraw turned out to be a mistake. He was tipped as 2014 champion Dan Evans’s main rival, but he could only finish eighth as Richard Bussell (AeroCoach) won.

When the sickness kicked in: Kenway during the 2015 National Hill-Climb Championships.

Kenway remembered: “In the morning I felt alright. But halfway up the climb my stomach turned. I got to the top and I was really, really rough.

“I ended up in hospital because I couldn’t stop being sick all through the night. I went to hospital that night at 9pm and Joe Clark (who finished third and lives near Kenway) ended up driving me home because I couldn’t drive and he had to stop to let me be sick.

“My wife had to take me to hospital and I spent the night in hospital under all sorts of drugs. I came out the following night. It wasn’t nice.

“It made me question what I was doing, certainly. You think it’s a short effort so it’ll be fine but that’s almost worse because you put your body into somewhere where it almost doesn’t want to go. You can see so much pain and anguish on the rider’s face, that’s why hill-climbs are so fun to watch!”

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“That was the worst physically I’ve ever been,” he admitted. “I might have had too much caffeine gels beforehand but either way I felt bad.

“I went down one of the back roads and had to keep stopping on the way down. That was horrible.”