Stanislaw Kowalski was born on April 14, 1910 in the village of Rogówek where he lived until the end of the 1930s. After his marriage, he moved to Brzeźnica. In 1952, due to the broadening of the boundaries of the military training ground, he had to move out of his newly built house and live in Lower Silesia, in the village of Krzydlina Wielka where he ran a small farm and worked as a railroad lineman. He has been living in Świdnica since 1979. Kowalski comes from a long-lived family his mother lived to be 99. For several dozen years Kowalski rode to work on a bicycle regardless of the weather outside.
On May 10, 2014, aged 104, Kowalski set the European record in 100m race at 32,79 s (in centenarian age category). No European centenarian man completed the run on such distance before him. However, Kowalski did not break the world record of Hidekichi Miyazaki of Japan set on Oct. 3, 2010 with the result of 29.83 s. Nevertheless, Miyazaki was much younger when he set the world record - 100 years, 11 days old.
When he competed at the Polish Veterans Championships on June 28, 2015, in Torun, Poland he became the world's oldest athlete. On that day, Kowalski ran the 100 metres in 34.50, threw the shot put 4.27 m (14 ft 0 in) and the discus 7.50 m (24 ft 71⁄4 in). By competing in those events, he surpassed the accomplishments of John Whittemore, who competed at 104 years 10 months. By virtue of his age being beyond 105 years old, he necessitates the creation of a new age division for World Masters Athletics, the M105 division of which he was the only member to have competed. Thus all of his performances are world records. M100 world record holder Hidekichi Miyazaki turned 105 on September 22, 2015 and two days later joined Kowalski as the second competitor in the division though Kowalski was 77 days older when he competed.
Kowalski credits his longevity to never going to the doctor and doing whatever he wants. He also says not to eat much during the evening. Kowalski became the oldest living man in Poland after the death of 108 year old Józef Żurek on March 20, 2018. Shortly afterwards, on 14 April 2018, he turned 108.