Quote from Anthony Robbin book "Awaken the Giant Within
"The failure of most individuals to grasp the difference between fitness and health is what causes them to experience the frustration of working out religiously and still having the same five to ten pounds stubbornly clinging to their midsection. ......Fitness is "the physical ability to perform athletic activity." Health, however, is defined as "the stake where all the systems of the body - nervous, muscular, skeletal, circulatory, digestive, lymphatic, hormonal, etc. - working in an optimal way......The biggest differnce between health and fitness comes down to understanding the distincition between aerobic and anaerobic excercise, between endurance and power. Aerobic means literally, "with oxygen," and refers to moderate exercise sustained over a period of time. Your aerobic system is your system for endurance, and encompasses the heart, lungs, blood vessels, and aerobic muscles. If you activate your aerobic system with proper diet and exercise, you burn fat as your primary fuel.On the other hand, Anaerobic means, literally, " without oxygen," and refers to exercises that produce short bursts of power. Anaerobic excerise burns gylcogen as its primary fuel, whicl causing the body to store fat. ..... When the levels of gycogen become excessively low, the anaerobically trained metabolism turns to blood sugar as it secondary source of fuel. This immediately disrupts your level of health and vitality.
So Aerobic exercise - burn fats built endurance
Anaerobic exercise - burns gylcogen and blood sugar built power.
Reduction of blood sugar affects you nervous system which uses two thirds of your blood sugar. Built up your base with aerobic exercise and have appropriate anaerobic training.FitnessHealth