Whatever it is that gives you that confidence will vary from person to person, but I do believe that it is the key to succeeding at anything in life - career, relationships, anything. ↗
If I'm exhausted and I just don't feel like it, then I don't do it. I am a human being, after all. But I also know I'm the kind of person who, if I take one day off, well, it's very easy for me to take the next day off and then quit exercising. ↗