Bradman volunteered for the RAAF on 28 June 1940 and was passed fit for aircrew. The service had more recruits than aircraft and instructors, however, and after four idle months in Adelaide the Governor-General, Lord Gowrie, persuaded him to transfer to the Army where his physical-training experience would be more useful. Commissioned as a lieutenant, Bradman was posted to the Army School of Physical Training at Frankston on Port Phillip Bay, charged with instructing PT instructors who would in turn train infantry divisions.
The role required hours of demonstration, weight work and parade-ground drill. Within weeks Bradman's right shoulder and back began to seize. Specialists at Heidelberg Military Hospital diagnosed fibrositis — a then-fashionable label for what would now be classified within the fibromyalgia family — and prescribed rest. He was invalided out of the Army on 30 June 1941. Press coverage was minimal: wartime regulations discouraged stories about Australia's most famous reservist being unable to soldier on, and Bradman himself disliked the sympathy.
For much of late 1941 he was bedridden. His wife Jessie later told Roland Perry that for weeks he could not lift his arms above shoulder height; one masseur, Ern Saunders, became a near-permanent fixture in the Bradman household at Holden Street, Kensington Park. By 1943 he had returned to stockbroking work in Adelaide but was warned by doctors he might never play first-class cricket again.
The condition flared again in 1945-46 as he juggled administrative duties and his new business after his employer Harry Hodgetts went bankrupt. When he finally led Australia out for the first Test of the 1946-47 Ashes at Brisbane on 29 November 1946, he had not played a Test in eight years and three months, and was widely expected to retire after that single comeback match.