What should you choose between yoga and the gym ?

It depends on what end result you are looking for. Strength and stemina can be gain from both yoga and gym. If you are looking for natural ways, go for yoga. If you are patient enough to seek progress after yoga, go for it. Gym on other hand provides you an image that you want your body to achieve. Everyday you will be fancied by new gym techniques, machines, repeatations, which might boost your confidence that you are gaining body progress. If you want this, go for gym. Going to gym needs discipline. Its not like you take membership and go to gym till you are excited and once your excitement fades away, you find it boring and hard to go to gym. Yoga on other hand will start coming effortlessly once you begin doing it. Try doing both individually for a month each and see what you find more interesting and challenging to pursue for longer time. Just ask yourself where I find myself more engaging and go for that. 

Yoga is different from Gym.Yoga is a union of body,mind and soul.Gym is working on physical level.Keeping body strong and flexible and healthy.In yoga there is less chance of injury or damage to the part of body whereas there is more chances of injury and damages to the part of body if not done correctly.

Yoga can be done at any age provided he can able to do.Gym is not recommended at very old age.

Yoga you can do at home or any comfortable place.For gym it is compulsory to visit gym.

In yoga one can remain  healthy,flexible and stress free and mently fit and also prevent and cure certain diseases.Therefore Yoga is the best choice.