P90X, or Power 90 Extreme, is a home exercise system developed by Tony Horton in conjunction with Beachbody and director Mason Bendewald. It claims to improve physical fitness in 90 days through a rigorous segmented training program combined with a nutrition and dietary supplement plan. P90X's advertising emphasizes "muscle confusion", a method of cross-training and periodization achieved through switching the order of exercises and incorporating new and varied movements.