Every time one of my athletes or friends say they do clamshells to help with their glute strength I want to scream. Clamshells have a place in rehab, especially post-surgery or for individuals who are just beginning to engage in exercise. But for runners, clamshells are not enough. Running demands dynamic, upright, and single-leg control. Clamshells are performed lying on your side, in a non-weight bearing position, and they do not train the glutes the way they're used during