Games are played to keep oneself fit. It depend on many factors that which one to play.
If you like to play Cricket then most probably you have to go outside and on the other hand if you like the table tennis then there is no need to go outdoor.
I can not tell you which one is better among the two because both are good and different games have their own significance. Like they say swimming is the best exercise. So all you need to know is the names of the games which you like.
To give you a general answer I think the people who are introvert play the indoor games while the people who are extrovert play the outdoor games.
For me both games are good. I can say it usually depends on the situation in which we are. Example in offices one can play only indoor games like badminton, TT etc, in break time. If we are on holiday we can play any outdoor game by going in the fields nearby our area.
I would like to vote for outdoor games and it is better than the indoor games. While playing outdoor games, we can give some exercise to our body. Also it will keep our mind fresh and active.
I prefer indoor games. You don't have to play in the sun and risk getting a tan or worse skin cancer. You won't be as fatigued either. High intensity games like squash or even tennis can be played indoors(as in a closed are..not at home).
Well as said both have their own significance and are useful for everyone who wants physical and mental strength both. I think outdoor games will keep a person fit and free from some problems associated with obesity. However, people can choose a substitue for outdoor game like walking, jogging which can help in solving obesity. But indoor games cannot be substituted hence i prefer them for mental strength.
Both have their own advantages. If you want to improve you physical fitness, you can play outdoor games more often. However if you are looking to sharpen your mind, indoor games are perfect. Game like chess is one of the excellent game that can be played in the home to hone up your skill and sharpen your mind :)