Ever wondered how Spartans, Victorian gentlemen, or extraterrestrial beings achieve those enviable washboard abs? Time to embark on a belly-busting journey through the ages (and galaxies)! Spoiler: No crunches in space. 1. Caveman Core: 2. Spartan Stomach: 3. Victorian Gentleman’s Gut 4. 1980s Disco Belly: 5. Alien Abs from...