Ride was born in Newstead, Victoria. He was the 5th child of Australian-born parents William Ride and Eliza Mary (née Best). His father was a pioneering Presbyterian missionary and his mother the daughter of a stonemason.
Ride attended three state schools in the country before being awarded a scholarship to Scotch College, Melbourne. There, he excelled in sport and won a senior government scholarship. On 14 February 1917, Ride enlisted in the AIF. Early in 1918, he joined the 38th Battalion on the Western Front. He was twice wounded, once seriously. Subsequently on 24 April 1919, he was 'invalided out' of the army.
Ride enrolled in medicine at the University of Melbourne. There he took an active interest in sport by participating in rifle shooting, athletics, rowing, cricket and football. He was the president of the Students' Representative Council from 1921 to 1922. Ride was elected Victorian Rhodes scholar for 1922. At New College, Oxford, 'Blue' Ride as he was known, became captain of boats and steward of the junior common-room. With only mediocre academic results, authorities were nevertheless impressed to the point that they rated him 'a good Rhodes Scholar' and a 'first rate fellow'.
Perhaps because of his natural ability for medical research, he was appointed professor of physiology at the University of Hong Kong on 21 October 1928. There, 'Doc' Ride as he was known, investigated in the blood groups of the peoples of the Pacific. In 1938, he wrote the book "Genetics and the Clinician", published in Bristol, England. Ride was commissioned in the Hong Kong Volunteer Defence Corps and was appointed a justice of the peace. He was a keen rower and played for the Hong Kong Cricket Club. Ride became an elder in the Union Church. Possessing the voice of a baritone, he helped to found the Hong Kong Singers in 1934.
Ride sent his wife and children to Australia in 1938 in anticipation of a Japanese invasion into the British colony. In 1941, Ride commanded the Hong Kong Field Ambulance. He was taken prisoner by the Japanese after Hong Kong fell on Christmas Day, 1941. On 9 January 1942, with the help of Hong Kong guerilla forces, he managed to escape to unoccupied Chungking, a feat for which he was appointed O.B.E. in 1942. While a colonel in the Indian Army, Ride formed and commanded the British Army Aid Group, headquartered in Guilin, Guangxi. This MI9 unit provided help, medical and otherwise, to POW escapees from Hong Kong while gathering intelligence. Due to his outstanding leadership after escaping, 'The Smiling Tiger' as he was nicknamed, was elevated to C.B.E. in 1944. From 1948 to 1962, Ride served as colonel commandant of the Royal Hong Kong Defence Force.
Ride was appointed vice-chancellor to a dilapidated, post-war University of Hong Kong in April 1949. 22 new buildings were erected and student numbers increased threefold in as little as 15 years after his appointment. He had been described as decisive, genial and authoritarian all at the same time. Ride enjoyed unwavering support among older staff but his tendencies to act like a father figure didn't endear him to those who were more recently appointed in later years.
Ride's marriage to Mary ended because of WWII. He married for the second time on 12 November 1954 at the Union Church in Hong Kong. Violet May Witchell, his second wife, had been his secretary before the war. Sir Lindsay died on 17 October 1977 in Hong Kong and was cremated. He was survived by his wife, two sons and two daughters from his first marriage.