Per-Olof Åstrand (October 21, 1922 – January 2, 2015) was a Swedish professor of physiology. He worked at the Royal Gymnastic Central Institute (GCI/GIH) in Stockholm 1970-1977, and 1977-1988 at the Karolinska Institute in Stockholm, Sweden. He was a member of the Nobel Assembly at Karolinska Institutet (1977–1988). Åstrand is considered a "pioneer", "legend" and one of the "founding fathers" of modern exercise physiology.