Samir Singh, the ultra-marathon runner who attempted to run 100km for 100 consecutive days, fell agonisingly short of the jaw-dropping achievement by just 36km.

The 44-year-old Singh, who began his daredevilry journey on April 29, ran for the 100th day on Sunday, but fell short of the overall target of 10,000km due to an illness that struck him while running on his 96th day – last Wednesday.

A bout of stomach infection and viral fever struck him that day, which meant he had to cut short his run and get admitted to a hospital for medication.

He was up and running the next day itself, but the lost kilometres on the 96th day cost him dear in his overall final timings calculated in his GPS watch, which he used as a timer.

"I felt unbearable pain in my stomach while running on the 96th day," Singh said. "While I continued running for a while after taking some tablets, the situation worsened and I had to get admitted to a hospital.

"I stayed put there all night, and felt better the next day. Hence, I decided to continue with my attempt. But in the end, even though I ran for 100 days, I couldn't complete the run," he added.

The man from Madhya Pradesh, who trains aspiring marathon runners in the city, would start his daily run at 4am and end it in the mid-afternoons with a couple of rest and food breaks in between.

While his attempt wasn't officially recorded, Singh is content about the fact that he could fulfill his ambition of running for 100 days non-stop.

"I set out to complete this challenge only due to my passion for running. I started by running barefoot, then with partially torn shoes, and then with proper shoes. When I began, there was nobody with me. Now various people ask me how I was able run so much," he said.

Singh wishes someone else can emulate his attempt, and even go on to achieve it.

"I don't think I will do this again. I have bigger goals now. But I hope someone else can can complete what I couldn't," he said.