What are some of the reasons for doing physical training ?
pleasure
endurance
strength
peer approval
flexibility

Strength, Flexibility, Endurance and  Pleasure are the main reasons for doing physical training.

Explanation:

The reason behind someone getting physical training is foremost to be gain strength as well as flexibility at the same time. When the strength and flexibility is achieved in the body the endurance and pleasure is the by product of the physical training then. Therefore according to the given question, all the options are applicable except the peer approval.

newton's first law of motion