MB ChB 1950, MD 1957.
Lyle was born in Newton-le-Willows on 1 October 1926, the son of J.S. Lyle, a medical practitioner. His grandfather and two uncles were also doctors. Lyle was educated at Ellesmere College and the University of Manchester. He was house physician at MRI and Crumpsall Hospital Manchester before serving in the RAMC. Lyle was then senior house officer at Victoria Hospital Blackpool and MRI. He was in general practice from 1954 to 1964 and from 1964 was medical director of Dista Products, Liverpool. Lyle was honorary lecturer on common fevers at the University of Manchester from 1962 to 1964. He was a fellow of the Royal Society of Medicine, the Heberden Society, MMS and St Helen's Medical Society and the Society of Occupational Medicine.