Depends, I used to have the same attitude, but then I realized that when I was lifting that I was not doing the proper movements, you know, I was jerking and snatching the weight,basically cheating myself. If your not doing this, and your able to keep good form, then no, I would say that it is a good mental attitude to have. Though remember that no matter what kinds of changes you are trying to make it is going to take time, and hard work, and allow your muscles to have a break and treat them well and everything should work for you.
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Reason
No other system of thought in history has proven more effective. If truth is the goal, rationality is the way. A good Virion will endeavor to hold a consistent set of beliefs and act in accordance with those beliefs. Think critically, act rationally.