Physical fitness is important in everybody's life even if they do not think that it is. You need to get up & stretch once and a while so that your muscles do not get cramped up. Even if you spend about a half hour a day just walking roughly and getting a little exercise you would feel better.
Just think if you did not get any exercise at all in one day. You would be so tired and worn down by the end of the day that you really would not get much of anything accomplished. Even if you would just walk up and down your steps at your house you are getting some exercise for that day.
That is if that is the only thing that you do for the day. You need to do exercise so that you can keep your body fit so that you are able to keep up with the world around you. Your overall health is better when you do some kind of exercise in the day even if it is just a little bit here and there.
Your muscles need the workout to keep them relaxed. It you do not keep them relaxed and free you could end up with muscle cramps throughout the night or even when you are sitting down getting ready to eat dinner with your family. Why don't you just try to take a walk around the block to get a little fresh air and get a little exercise? Another thing that you could do is walk trough the house more so that you can get exercise even if it too cold outside for you to go out there.
In all reality it is not good to sit in one spot for long periods of time because then you really do not want to get and more around because all the muscles think that this is how you want to be even longer. We all need to listen to our body once and awhile so that we do not get too lazy and just sit around and gain more weight from it.