So like recently I've been making pretty good gains, but they started to wear out not so much because I'm a lifting machine, but mainly because my abs couldn't support me. I'd attempt to bicep curl, and my body would rock back and forth, taxing my form and making me have to swing even further. Tricep cable pulldowns - same story. It was my abs that prevented me from going further. I deadlift and squat regularly, so it's not like I was totally neglecting my core. Now that I actually started weighted ab work (last ab-workout was oh, let's see...two years ago!), my lifts are increasing again.
That is all.