First off, reread the title of the thread- it's not a "why" question, but clearly asks if they are for chest, back, or both. I took the same anatomy everybody else took (unless the human body has recently changed) and I disagree with Eric's assessment of the role that the pecs play in pullovers. Just because he said it, and he has three thousand posts, doesn't mean his word is that of God Almighty. The condescending way he responded was not helping anyone learn anything, which can be inferred by the way he buffered it with his "didn't want to be a smart akeck" edit. I might be new to this forum, but I'm not new to training people or addressing these kinds of questions. The average person has no interest in the importance of the glenohumeral joint. They want to know- as did the OP- if pullovers are back, chest, or both. If the OP was unable to figure that out on his own, and he came here to ask about it, how useful is an answer that he probably won't understand? Learn to read your audience. The reason I oversimplified my response was to purposefully NOT confuse him with the entire anatomy of the shoulder joint. How helpful is it to a newcomer when they ask a question to say, "I don't believe there are chest exercises." How confusing is that? How dos that help anybody learn anything. Or is it because Eric said it, it must be true? Funny, the ACSM would disagree.