Sometimes it gets easier to train the more you do it. It’s like toughening yourself up to handle more physical stress. You might have felt pretty pooped from the first time trying something. But then the next day you realize you have the energy to do it again.
Sometimes it’s just time to rest. You’re tired not because you’re weak, but because you’ve done a lot.
It’s important to figure out when to push and when to train. I find that if I default to train, I benefit from waiting until the moment I have to get out and train to see whether I’m really ready or not. And if I do start training, I get to feel how much energy I really have. Rather than trying to mull over it in my head beforehand, I simply know I will come to the moment of truth.
With this come the element of design. Figure out what level of training, and the frequency, that you can reasonably do. You can only really find out by trying. Yes, you may overdo it at first. Then pull back. If it’s easy, though, have no qualms about pushing a little more next time.