I thought, that there must be something wrong with me. I sound like an old smoker when i race. But then an elite male passed me. He sounds just like me! they make it LOOK easy, but effort is well effort, so hard effort will make you puff. Just make sure that you are able to breathe, and than there are no underlying health issues that need addressing. Many time as people approach that puff point, they start to panic a little bit so the breathing goes all over the place, and/or they start actually holding their breath.
smile
Han