Concede the point about speed, however circulation remains. The giraffe, while being two feet taller, has four legs and too much blood pooling in the lower legs is a constant concern, as is extreme lower leg blood pressure. The Lorenvolk are even more vertically oriented with a higher heart and almost as tall, and while weighing half as much as a giraffe, has two legs. Shouldn't keeping blood pressure down be a chief concern?