Exercise

Physical exercise is manual activity that develops or maintains physical fitness and overall health. It is often practiced to strengthen muscles and the cardiovascular system, and to hone athletic skills. Frequent and regular physical exercise boosts the immune system, and helps prevent   diseases of affluence such as heart disease, cardiovascular disease, Type 2 diabetes and obesity. It is also improves mental health and helps prevent depression.
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(v. t.)
To set in action; to cause to act, move, or make exertion; to give employment to; to put in action habitually or constantly; to school or train; to exert repeatedly; to busy.
  

(v. t.)
To put in practice; to carry out in action; to perform the duties of; to use; to employ; to practice; as, to exercise authority; to exercise an office.
  

(v. t.)
To occupy the attention and effort of; to task; to tax, especially in a painful or vexatious manner; harass; to vex; to worry or make anxious; to affect; to discipline; as, exercised with pain.
  

(v. t.)
To exert for the sake of training or improvement; to practice in order to develop; hence, also, to improve by practice; to discipline, and to use or to for the purpose of training; as, to exercise arms; to exercise one's self in music; to exercise troops.
  

(v. i.)
To exercise one's self, as under military training; to drill; to take exercise; to use action or exertion; to practice gymnastics; as, to exercise for health or amusement.
  

(n.)
The performance of an office, a ceremony, or a religious duty.
  

(n.)
The act of exercising; a setting in action or practicing; employment in the proper mode of activity; exertion; application; use; habitual activity; occupation, in general; practice.
  

(n.)
That which is done for the sake of exercising, practicing, training, or promoting skill, health, mental, improvement, moral discipline, etc.; that which is assigned or prescribed for such ends; hence, a disquisition; a lesson; a task; as, military or naval exercises; musical exercises; an exercise in composition.
  

(n.)
That which gives practice; a trial; a test.
  

(n.)
Exertion for the sake of training or improvement whether physical, intellectual, or moral; practice to acquire skill, knowledge, virtue, perfectness, grace, etc.
  

(n.)
Bodily exertion for the sake of keeping the organs and functions in a healthy state; hygienic activity; as, to take exercise on horseback.
  

Used to complete a proof in technical books when one doesn't mind a handwave, or to avoid one entirely. The complete phrase is: "The proof [or "the rest"] is left as an exercise for the reader." This comment *has* occasionally been attached to unsolved research problems by authors possessed of either an evil sense of humour or a vast faith in the capabilities of their audiences.
[Jargon File]
(1995-02-20)

To implement the right of the holder of an option to buy (in the case of a call) or sell (in the case of a put) the underlying security.