Difference between Gym and Yoga

I think title of this is post is little vague but I put it for people who come here without any Yoga background or little knowledge of Yoga. Title of this post should be "What is the difference between Yogasana & Gym?"

Many people consider Asanas and gym exercise are same and practice Asana like exercise. Asanas are much more than exercise they promote and maintain the physical and mental health.

Yogasana	Gym
There is an effect on both the gross and the subtle body.	Only affects the gross body.
Promote physical and mental health.	Promote only physical health.
The movements to assume and release any asana are slow and without any jerk.	Performed in a fast and speedy manner leading to exertion and fatigue. All the movements are done with a jumpy and jerky element.
The maintenance of posture is more important than the movement part of it.	The maintenance phase is rarely observed and if it is present it will be for a very short period.
The effect of asanas is more on the trunk portion of the body.	In exercises the movements of the extremities are more prominent and influential. Their effect on the trunk part is secondary.
In asanas the spinal column is moved in almost all the directions in its possible range of movements.	Sequence is also rarely observed in exercises. The movement of the spine is fast and the counter action is absent.
Muscle-building is not the aim of asanas.	Heavy muscle masses are built through exercises for more and more muscular strength.
In asanas skeletal muscles are passively stretched and therefore the muscle tone cannot increase beyond a particular level.	In exercises, there are heavy and sustained (isometric) muscular contractions and active stretching of muscles against some graded resistance, e.g., exercise on the bullworker' instrument.
As the voluntary efforts are withdrawn in the final stage of asanas the activity of the motor cortex is greatly reduced or even stopped completely.	In an attempt to achieve the goal in exercises, one makes lot of voluntary efforts. These increased efforts cross the normal limits of endurance and stamina.
Asana can be done anywhere including remote area.	You need a dedicated space for exercise.

Thus we find that the basic purpose, motivation and therefore the technique of asanas and exercises are quite different. Their mechanism and the effects are also different.

Therefore there should not be any confusion regarding asanas and exercises and their nature.

Namaste.