Aramnau was quoted by local media Tuesday as saying he sustained the injury at a domestic competition last weekend. He said he pulled a thigh muscle and will be sidelined for about two months, so "the Olympics are now over for me."
He did not specify which thigh he injured.
Aramnau won gold in the 105-kilogram category in Beijing four years ago, breaking several world records in the process. He was later banned for two years because of drunk driving convictions, but had been training hard in recent months in an attempt to defend his gold medal.