I used to play DDR all the time, and then my mat broke. In the past I was talking Ballet classes as well so I was in shape, but it didn't give me muscles. Dancing is a good way to burn calories, a good cardio workout and a fun way to get your body moving.
Now I try to do the Bad Apple dance whenever I can. It's fast and rather intense. It will make me feel cool in my Touhou costumes as well.
Start out simple it you are out of shape, like twice a day and then do more for longer periods of time.
Newcon 2013 (Portland OR):
Sylveon - Pokemon: 50%
Akihito Kanbara (Idol) - Kyoukai no Kanata: 5%
Eren Jaeger - Attack on Titan: 10%
Sakuracon 2014 (Seattle WA):
The Hooded Man - Final Fantasy 4: The After Years: 0%
Yuuka Kazami - Touhou Project: 0%
Witch Elly - Puella Magi Madoka Magica: 0