By this point in time, we all know that there are better options for your abs than situps, but in having that knowledge, planks, Paloff presses, and other stability-based tools—as great as they are—can feel redundant with the absence of variety. It’s important to review the abdominals’ functions to better equip you with the right moves for your arsenal. Here’s a quick lesson.

The core of the matter: A better way to train your abs

Some people think “core” training deals with the good old six-pack—the superficial abs muscles you can see. But in truth, the core comprises everything between your hip bones and nipples. That means properly training it involves training from multiple angles, in several directions. Your abs serve four major purposes: