Which side of the elbow? Pinky or thumb side? How high up in the back does it start? Reason I ask is that the ulnar nerve comes off the medial cord which gets it's roots from C8 and T1 so it's more in the neck and comes down to the medial aspect of the elbow and innervates a lot of the hand muscles and a couple of the forearm flexors. I don't really see how it would effect benching except with a little bit of grip weakness. The ulnar nerve doesn't innervate anything that is involved in bench pressing except those couple forearm flexors but you would still have function of most (FCR, 1/2 FDP, FDS, PL).