Today I really dogged it man. I ate too much, and I did my training halfheartedly. I still stuck to the PCP but only in the letter of the law, not the spirit. Sometimes that's all you can do to get by.
I get these low energy days after about 4 weeks of consecutive training. I think the body just knows when it's getting pushed too much and powers down some systems.
Everything in the universe works in wave patterns, from the atoms in your hand, to the light coming from your screen now, to the cycle of your breathing and heart. We seem to think that we are somehow exempt from this cosmic law, that we can keep going up and up without ever experiencing the downs. Of course a wave that only has a peak and no trough is impossible.
The wisest people I know have an innate sense of these patterns and work to attune themselves to them. I am trying to be more like them, and so won't beat myself up over being lazy and inattentive today.