Lantana, Fl — MyBodySite.com, a social networking site similar to Facebook, has grown its membership to 13,000 registered members and expects further growth in the coming months, says John Cummings, president of MyBodySite.com. In addition to allowing members to network and compare workouts, the site recently added a meal-tracking component and a custom workout builder. MyBodySite.com was designed to build community and boost retention, Cummings says.