Cardio, also known as “aerobic” training, implies the completion of low-intensity, prolonged activity, such as jogging, running, skipping and swimming.

The exertion during this type of training is pretty low and the main points of adaptation are the lungs & the heart.

When doing cardio, you primarily use the slow-twitch muscle fibers, which were built for endurance and for that reason, they have the lowest power output & potential for growth.

Last but not least, cardio training makes the body use oxygen to burn muscle & liver glycogen, as well as fatty acids.

This type of training mainly results in increased capacity for cardio endurance during low-intensity, prolonged activities.