I love to go to swimming.
Today have been the first day, from December 20th December, that I have come back to swim. The reason is because the swimming pool was closed from that day to do cleaning tasks. It’s needed to do it once a year.
I know that it must do exercise (due the age, the mind,) but the point why I chose, and that why I love swimming. Firstly, because is a sport with low body impact: my knees give thanks for that. Secondly, it’s outdoors swimming pool and I like to do sport in contact with the environment and, usually, if I can, I'm going to go at noon: sun is life; and finally, because I can spend the time that I want: for example 30, 45, 20 minutes… it doesn’t matter: no timetable, open all day and all week.
In summary, I recommend you do daily exercise since you feel better, and outdoors instead indoors.