September 23, 2013 5 Squat Biomechanics: Butt Wink – What is it, What Causes it, & How Can it be Improved? By Bret Contreras | Glute Training, Low Back Reconditioning, Spinal Health, Strength Training, Stretching/Flexibility | 48 Comments “Butt wink” is a common issue for the majority of squatters. But what exactly is butt wink, what causes it, and can it be improved? If so, how? In the… Read More