sports physiology is mainly a discussion of the ultimate limits
to which several of the bodily mechanisms can be stressed.
To give one simple example: In a person who has extremely
high fever approaching the level of lethality, the body metabolism
increases to about 100 percent above normal. By comparison,
the metabolism of the body during a marathon race
may increase to 2000 percent above normal.

Female and Male Athletes​:

In general, most quantitative values for women—such
as muscle strength, pulmonary ventilation, and cardiac output,
all of which are related mainly to the muscle mass—vary
between two thirds and three quarters of the values recorded
in men. When measured in terms of strength per square
centimeter of cross-sectional area, the female muscle can
achieve almost exactly the same maximal force of contraction
as that of the male—between 3 and 4 kg/cm2. Therefore,
most of the difference in total muscle performance lies in the
extra percentage of the male body that is muscle, caused by
endocrine differences.

male hormone testosterone causes increased muscle mass in males as compre to females in which estrogen causes the body changes different to men..

so in the end of this chapter students will be able to understand the changes DURING  EXERCISE IN

• MUSCLES 
• RESPIRATION
• CARDIOVASCULAR SYSTEM
• BODY HEAT
• BODY FLUIDS

and also about usage of drugs in athletes