The Perils of Viagra: A Brief Lesson

A man was walking in the jungle one day and came upon his friend Tarzan who was sitting on the ground.
Tarzan looked dazed. He had bruises all over his body. He was bleeding from several places and there were healed wounds on his body.
The man said, "Tarzan, what happened? You look like crap."
"I know. It's the Viagra I've been taking."
"Viagra. What the hell does Viagra have to do with this?"
"You know Jane wanted to improve our sex life and got to take the stuff. And it's really been great."
"Yeah, but how did you get so beat up."
"Well, when I go swinging through the jungle and try to land on a tree, I keep coming up about six inches short."