Killer Workout

Two years ago, a young woman named Valerie was burned after entering a tanning salon. Now, her twin sister, Rhonda, runs a local gym where, all of a sudden, people are being murdered.

Killer Workout is a 1987 horror movie directed by David A. Prior, starring David Campbell, Marcia Karr, Fritz Matthews. It holds an IMDb rating of 4.6/10 from 3,388 votes and runs 1h 25m.