New Delhi, March 20 -- A week into his big expedition, Satish Gogineni's progress was down to a crawl. His 126kg sleigh kept sinking in fresh snow and it took a mighty effort to drag it over short distances. Eight hours of constant effort got him across just 7km each day. At this rate, it was clear that he would run out of rations before reaching the finish line at the South Pole.

"I would bend over and pull with all my might to see my sleigh move a few inches. It was painful and I was really miserable, especially since I was targeting a daily mileage of around 20km at that point. When you go through these moments, it really puts doubts in your head," Gogineni, 42, says.

For the next few days, he battled on until conditions improved. An...