Describe the adaptations to regular exercise that lead to an improvement in function of the body to perform work

Answer 1

Exercise of duration longer than a few minutes requires an increased provision of O2 and metabolic substrates to muscle so that ATP for muscle contraction and relaxation is continually replenished. Mitochondria are the site where fatty acids and carbohydrates are oxidized, producing ATP. Mitochondria proliferate in endurance-exercise trained muscle, increasing the structural proteins and enzymes necessary for complete oxidation of macronutrients. Furthermore, the exercise-trained muscle is better able to: (a) store glycogen and triglycerides, (b) transport glucose and fatty acids from the blood across its membrane into the muscle, and (c) increase in capillary density. These adaptations ensure that delivery of O2 and substrates to the trained muscle is increased. In addition, the exercise training results in a more efficient heart muscle, thereby enabling the muscle capillaries to be adequately perfused.