Incredible, but true. In 1948 he started running sixty 400-metre intervals a day, with only a 200-metre jog in between. In 1955 he trained harder than ever, running as many as ninety 400-metre intervals daily.

From:Sri Chinmoy,Emil Zatopek: earth's tearing cry and Heaven's beaming smile, Agni Press, 1980
Sourced from https://srichinmoylibrary.com/ez