Exertion Games

Lots of references to follow and makes some sensible sounding points for things you might want to consider when design such an interface.

Mueller, F. ‘., Gibbs, M. R., & Vetere, F. (2009). Design influence on social play in distributed exertion games. In Proceedings of the 27th international conference on Human factors in computing systems (pp. 1539-1548). Boston, MA, USA: ACM. doi:10.1145/1518701.1518938ß