In 1941 with the start of the Great Patriotic War he volunteered for the Red Army. He fought under the general Mikhail Kirponos. Chukarin was wounded in action, taken prisoner of war near Poltava (Kiev Cauldron) and sent to a prisoner camp in Sandbostel. He then went through a chain of 17 prisoner camps and by the time when he was freed in 1945 weighed only 40 kg. He was not accepted back to the sports institute in Kiev, and studied in a similar institution in Lviv.