For breathing it's mic position and filters. That weird circle with nylon in front of the mic for some folks is to block out breathing. The microphone being right under the nose or near it means you will get that a lot. Aim it down toward the mouth and a lot of the breathing goes away. Professionals know how to breath quietly. When Jeremy Clarkson says, "it's the greatest burger .... In the world." That pause is actually hom breathing and moving his head away from the mic a little.