One can stay physically active by walking, running, biking, swimming or exercising at a gym. One should do proper warm up and cool down.
Saw Maung Maung Htwe (Intake of 64) was Inter-Institute Marathon Champion. He stays fit by running daily and competing in long distance events all over Myanmar. He is the most senior among the active Marathoners. In 2018, I met him in Mandalay, where he had just completed his long distance race. We had a quick chat. In 2019, I saw him running all the way to attend the Reunion and Acaiya Pu Zaw Pwe of the Combined 1st BE Intake of 64 and 65.
Khin Maung Myint (M71) stays active by competing in events in several countries. He represented RIT in Rowing. There are three Khin Maung Myint in the Class of 71.
Mentally Active
One can stay mentally active by reading, writing, playing word games & cards, and meditating.
One can also exercise one’s mind (e.g. recalling the events associated with a picture).
Ivan Lee’s mother lived up to be 102 by being mentally active. She played Mah Jong two hours daily.
Socially Active
One can stay socially active by attending events (e.g. Toastmasters International, Meetups, celebrations).
One can also be active on the Social Media.
I have 2600+ posts in my web site hlamin.com I am Admin or Moderator in selected Facebook groups such as RIT Updates Fun with Learning RU Centennial