Leg day is tough no matter what—but if you're Jessica Biel, apparently it's a glutes-burning, legs-shaking kind of tough.
Jessica's trainer Ben Bruno (who also trains Kate Upton and Chelsea Handler, NBD) posted an Instagram video showing the actress and wife of Justin Timberlake doing a skater squat combination that looks absolutely insane.
Even Bruno realizes how intense the combination is. He captioned the post, "Wanna see something crazy?" Duh! Of course you want to see the moves that help build Jessica's famous butt and toned physique.