Quick Way To Get That Second Wind

At fun runs every week a friend and I would run together for a while then he would take off. I tried to keep up with him all the way through and could not. One time at a race I saw a person raise their arms and yell “yeah” in a loud voice and then take off at a greatly increased speed. I this was so cool so I decide to try it, but what would every one think if I just shouted out? So one evening when it was just my friend and I running together I was slightly ahead of him and he was just getting ready to pass me. I knew that if I let him pass I would never catch him. As we were just getting ready to turn a corner, I happened to look up and see a stop sign. On a sudden impulse I raised my arm slapped the stop sign, shouted yeah and took off running. My friend never caught up with me. That was the first time I ever finished before him. I was baffled about why this would work. After thinking about it I decided it had something to do with getting the air out of my lungs and taking in fresh.