Declining skill or fitness level from taking a break from exercise is formally referred to as

a. progression
b. specificity
c. overload
d. reversibility

The correct answer is D. reversibility

Explanation:

Reversibility principle says that when a person goes an extended break from exercise his/her fitness level reverse or gets declined day by day because  the muscle becomes weak and shrinks when it is unused.

Therefore when we take a long break from physical activity the fitness and skill level decline which we got from regular training but it can again be gained if the person resumes the workout regularly.  

In a study is was observed that skill does not get decline easily and it requires a long time for skill to decline. Endurance, flexibility, strength and other components of physical fitness can easily decline over time. Therefore the right answer is D. reversibility.

i believe is was

since you have not provided the options here i   am going to give you general overview about hormone.hormone are actually the part of endocrine system in our body and produced by the endocrine glands. the hormones act like a chemical messenger   within human body. once produce by the glands they   travel through the blood stream and reach at specific or target tissue and organs   which result in control of our body function. the hormones are specific in their work and work on only the targeted tissue or organ   . with the of hormone endocrine system regulate the heart rate , metabolism, our mood and   growth as well as the development and even the sleeping cycle etc. they actually are the messenger for body cell and organs .