David Gregory "Dave" Smith (born 24 July 1955) is a retired male race walker from Australia, who represented his native country at two consecutive Summer Olympics, starting in 1980 (Moscow). His best Olympic result was finishing in tenth place in the men's 20 km race at the 1984 Summer Olympics.
Can we infer the following?
David Gregory Smith retired from race walking due to an injury,
It's impossible to say