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flexibility decreases.
Previous injury: Injuries to connective tissues and muscles ultimately lead to
reduced flexibility
Physiological factors determining endurance.
Aerobic capacity:-
(1)oxygen intake
(ii) oxygen transport
(iii) oxygen uptake
(a) Energy reserves,
(b)Lactic acid tolerance,
(c) Movement economy,
(d) Muscle composition
Oxygen Uptake:- It is highest rate at which oxygen can be taken up and consumed
by the heart per minute.
Cardiac Output:- The cardiac output is simply the amount of blood pumped by the
hear perminute.Hydration and Endurance Exercise: - Sweating is normal
physiological response to prolonged exercise, required for the dissipation of hear
produced during energy metabolism.
Effect of exercise on the cardiorespiratory system
(i) Cardiac output is the amount of blood pumped by the heart in 1 min. This
increases directly with increasing exercise intensity.
(ìì) The heart rate increases from a resting rate of 72 beats / min to 150 beats / min
or even more.
(ííi) The stroke volume, meaning the amount of blood pumped into the Aorta with
every heartbeat,increases from a resting volume of 70-90 mL to 100-120 mL per
beat.
(ìv) Exercise increases the plasma volume of blood by 12 Op :, but total blood
volume may reduce slightly.
(V) Blood flow is redistributed with more blood going to the muscles, heart and
skin, while blood in the kidneys and abdomen is reduced.
(vì) Blood pressure increases due to exercise because there is more blood flowing
in the blood vessels.
Effects of exercise on muscular system.
Size and shape of muscle changes: Regular exercise changes the shape and size
of the muscle. Cells of the muscles are enlarged which change the shape and size of
the muscle.
Correct body posture; regular exercise keeps the correct posture of the body by
strengthening the muscles. The postural deformities do not occur. If there is any
physical deformity, then it is removed.
Food storage increases: the capacity of food storage in body can be enhanced by
doing regular exercises. This stored food can be utilized immediately when required.
Toned muscles: regular exercise helps in keeping the muscles in toned position.
Muscles become firm and maintain a slight, a steady pull on the attachments.
Efficient movement of muscles: The movement of muscles becomes efficient and
smooth. The movements during different activities become attractive.
Change in connective tissues: the connective tissues become powerful. These
tissues can bear the stress of strenuous activity.
Increase in Tidal air capacity: by doing regular exercise it has been noted that
there is an increase in the amount of tidal air capacity of an individual.
Decrease in rate of respiration: When a beginner starts exercising his rate of