One of the Masungulo males chasing away a lioness from a warthog kill in order to let the cubs feed. Photographed by Robert Prehn at Pondoro Game Lodge.
There's what I'd call effort or discomfort - this emerges as we push into higher reps. Some days, the whole workout is effortful. I think this can be good for us in the right dose! It trains us to be stronger and more physically mentally capable.
On the other hand, there is a type of pain that is physically bad for you. If you can imagine the pain associated with trying to lift more weight than you should (in a movement you're not familiar with) - that's what I mean! In this case, I don't think this is always good for us. Contrary to popular belief, damage isn't always good. Some damage only harms us.