Watch as Brynn Jinnett, founder of Refine Method, demonstrates how to activate and firm sedentary backsides.

More butt-toning videos from top trainers:

Cassey Ho, Pilates instructor,
Try these power-Pilates exercises to target saddlebags and outer thigh bulge.

Kristin McGee, yoga instructor,
Moms-to-be, watch Kristin demostrate yoga moves to keep your butt in shape during pregnancy.

Mary Helen Bowers, founder of Ballet Beautiful
Ballet-inspired moves to lift and tighten a saggy butt.