To get the most out of your plyo box workouts, you’ll want a plyo box that’s tall enough to challenge you—but not too tall to jump on top of. (Remember, if you’re sacrificing your form, you probably need to scale back.) This just-right height will vary from person to person. So start with a shorter box, and look for an adjustable or 3-in-1 box you can use to try a few different heights.