So... quick little poll... do you prefer bench pressing a) all the way down to the chest (or off by only an inch-ish) or b) until your upper arms are parallel to the ground? I've heard so much different stuff including, from a personal trainer: "90* counts as a full rep" and "beyond 90* is where injuries happen"... from other people I've heard that just doing 'partial reps' is a way to hurt yourself... is this question going to get the same array of responses as a question like 'which cigar is the best ever'?
