Well I started boxing and I don't have a personal trainer but the coach of the gym asked me if I was weightlifting. I said I did and he said scrap it and told me to do long distance running mixed with intervals (roadwork), crunches, dips, chin ups and skipping. He was going on about how weightlifting is bad for boxers because they shorten the muscles and flexibility is lost. I still want to weightlift, umm what should I do? and does weightlifting actually hinder your performance in boxing?