Léon Marchand has broken the world record in the 200-meter individual medley at the world championships in Singapore, clocking 1 minute, 52.61 seconds to surpass the 1:54.00 set in 2011 by American Ryan Lochte.

The United States team at the swimming world championships in Singapore is battling a case of “acute gastroenteritis” that compromised performances on the opening day of eight days of competition in the pool.