British triple-jumper Phillips Idowu broke down in tears while on a trek with children in Zambia for charity Comic Relief.
The 34-year-old, who failed to win a medal at last summer's Olympic Games, took on a five-mile walk with the youngsters, who carry out the trek on a daily basis to get to school.
"I'm an athlete who competes and comes back with a gold medal," The Sun quotes Idowu as saying. "But doing that walk, after an hour my back was aching. I asked one kid if he was OK and he said he didn't find it hard anymore.
"My life is nothing to what these kids have to endure. I was brought to tears by the talent and determination of those children who want to make their own lives better."
Idowu, singer Mel C, actress Chelsee Healey, comedians Dara O'Briain and Jack Dee, and DJ Greg James are rowing the Zambezi river to raise money for the local children.