This is not your father’s rock & roll. Actually, it’s your grandfather’s rock & roll. Young@Heart is a chorus of seniors, all between 70 and 90-something, who sing rock, R&B and punk tunes, and this documentary follows the troupe through rehearsals and a concert in their Northampton, MA hometown. In between there are several MTV-style videos (including “I Wanna Be Sedated”) and profiles of several chorus members, but the film skates around the question of how they feel about performing in an ensemble that simultaneously exploits and celebrates their advanced age. Nevertheless, there are many moving moments, largely due to the added poignancy of their renditions of songs like Coldplay’s “Fix You” and “Forever Young.” It’s a testament to the chorus and their leader, Bob Cilman, that their story overcomes the film’s news-magazine-style format — it was originally made for British TV, and looks it.