sentences:  In February 2011, after Corinthians were eliminated from the 2011 Copa Libertadores by the Colombian team Deportes Tolima, Ronaldo announced his retirement from football, concluding an 18-year career.In an emotional press conference on 14 February, he cited pain and hypothyroidism as the reasons for his premature retirement.He discovered he had hypothyroidism – a condition which slows down metabolism and causes weight gain – during tests with Milan in 2007.