When i do a hard track workout, or a race over a mile it seems like my forearms and shoulders are severely filled with lactic acid, moreso than my legs, probably about 1.5 miles in a 2mile or about 2 miles into a 5k, I'm not going out too fast since i usually negative split. In fact my arms are the first thing to go in a hard race. It is really uncomfortable, and hard to go fast when you can't pump your arms. Anyone else have this problem, and know why or how to fix it?