Athletic fit is when movement begins to take on a designated purpose. You begin to set goals with your moment. It can start with healthy fit, for instance you plan several extra trips of moving your muscle during your daily routine, or you take on more intensity in your movement.
There is a lot of health benefits when you start moving your muscles at a certain intensity for a period of time. It triggers chemical reactions that actually make you healthier, you grow more energy units in your cells, the capillaries (vessels that take oxygen to your muscles) increase in number and size, the heart, lungs, immune, hormonal and nervous systems become energized to make themselves better. This only happens with muscle movement.
Athletic fit starts with setting and reaching goals. Athletes plan a time each day to either cover a certain distance, or perfect movement within the time or distance they travel. This carries over to a training type of mentality. They begin to train their bodies to do something physical, such as preparing the muscle to do a certain race, or event like the 3 day 60 mile walk.