The Argentinosaurus had an estimated weight of 100 tons (a male African elephant can weigh up to 7 tons) so you can safely consider that it was a slow-moving animal, but not clumsy.
The vertebraes of 1.65 meters high were articulated together by complex interlocking structures to support that weight.
The Argentinosaurus came to measure up to 40 meters long and lived about 65 million years ago (Upper Cretaceous) in the area of Plaza Huincul and Cutral Co, in the province of Neuquén. Like all large sauropods, it fed on the foliage of tall trees.