Endurance is very significant component of physical fitness, which is determined by the following physiological factors.
1. Aerobic capacity :- To perform an activity continously energy is required by the muscles which can be supplied in the presence of oxygen. Therefore the ability or organism to maintain the adequate supply to oxygen to the working muscles for energy liberation is important for endurance performance. The aerobic capacity depends upon:
a. Oxygen intake :- The oxygen intake depends on the vital capacity which further depends on lungs size, no of active alveoli, respiratory muscle and the size of the chest cavity.
b. Oxygen transport :- The oxygen transport depends on the amount of exygen, which the blood has absorbed from the lungs and the ability of th circulatory system to carry this quickly to the working muscles. The amount of oxygen absorbed into the blood depends on the speed of blood flow through the lungs and on the blood haemoglobin. The concentration of blood haemoglobin can be enhanced by training. The transportation of exygenated blood depends on the capacity of the heart. This capacity can be improved by training.
c. Oxygen uptake :- This depends on the rate of defusion, which determines the speed of blood flow, temperature & partial pressure of oxygen in the blood and of carbon dioxide in the muscles. The speed and amount of oxygen consumption depends on the no. size & metabolic capacity of mytochondria and fortunately can be improved to some extent through training.
d. Energy reserves :- The aerobic capacity depends on the muscle glycozen & sugar level in the blood. This can be enhanced by the training.
2. Anaerobic capacity :- The working capacity of muscle in abrence of oxygen is called anarobic capacity more ro less Anarobic capacity is required in all kind of endurance activities. Anaerobic capacity is depned on the following factrors
* Phosphagen store :- Means stronger of ATP and CP for producing energy.
* Buffer capacity :- Means total storage of Alkali reserve in the body to fight against the effect of lactic acid is called buffer capacity.
* Lactic Acid Tolerance :- The ablity to tolerate the higher concentration of lactic Acid is a significant factor in determining anaerobic capacity.
3. Movement Economy :- Energy may be saved if the movements are correct so the economical movements are necessary for endurance performance
4. Muscle composition :- The slow twitch fibres of muscles are best for endurance activities.
