This *is* interesting reading. I'm in the younger set in this thread (I'm 27) and I feel worst the week before my period starts. No energy, draggy feeling, I need more sleep, any exercise is a real chore--though I do feel a little better after I exercise, if I can force myself to do it. Definitely "less pushing", as Irulan said, only in my case I often feel like I can barely push at all. Just a sad little 13mph spin or so, and usually a short ride. I feel hugely better the day after my period starts. Then I'm strong, raring to go, all's well with the world. 20mph? Great! Let's go!

I do wonder what all's going to happen when I hit 40, when things are this bad for me at 27.