So for example, if we're diving or sprinting, let's say 100 meters or swimming 50 meters, these are the muscles that are basically used. So let's discuss the fast glycolytic. So fast simply means these also have a fast contraction speed and that's because they break down ATP quickly. Now, unlike these two muscles, these muscles basically do not use oxygen. So that means we have a low concentration of oxygen. So we do not have too many capillaries and we use anaerobic respiration.