It just so happens that the best day of my current split falls on Mondays. And come to think of it, I should just do it this way all the time. Today was my Back/Bi/Abs day. All the favorites. And wow, I had no idea that my body would respond so well to lifting heavier, but it has and it's showing me mad appreciation :D
Tris feel harder after last week's heavier session, and I found myself giving em squeezes throughout the day, thinking "Wow, are these really MY arms!?!?! Awesome!". Another nice thing: putting my hand on my hip only to notice that there's less squishyness there and more dense muscley-ness. What a delight, haha! If there's anything that will make me not want that ice cream cone this summer, it's gonna be that little reminder when I squeeze the old Tum.
Ab work sucks when you first start working out. Pumping out a few crunches makes you feel uncomfortable like an irritated hermit crab lyin on its back. But you gotta push through, and then you slowly start to realize that all those annoying people who talk about how great it is to have a strong core actually have a point, even though they're still annoying. Having a strong core just feels good - I really can't explain it any better than that!
And back work, well let me just put it this way. Backs are beautiful. And having great posture expresses that confidence and self-esteem that lifting gives you. So back work also goes in my favorite glamour muscle group.