The following is an excerpt from my book
Achieving Total Muscularity
Suppose we ran an experiment. We take two bodybuilders of similar age, height and weight, and have them do the same amount of exercise each day for three months. The only difference is that one of the bodybuilders was highly motivated. In each training session, our motivated trainee used heavier and heavier weights, forced out last repetitions and prepared mentally before the actual training started to make each workout more intense than the last one. Our motivated trainee learned to concentrate fully on the muscles worked, making each rep count. The other trainee never missed a workout, but to put it in the vernacular, his heart was not into what he was doing. He would talk to others in the gym between sets, lose concentration in the middle a set and start thinking, "how much more before I can relax in the sauna?" The results: the motivated athlete, of course, has to make better gains. Bodybuilding is like a bank, you get out what you put in with interest. Half hearted attempts net mediocre results in bodybuilding. I've seen so many students use the same weight, the same sets and reps for years and not change their physiques at all. The reason is lack of positive self-motivation. You can lead a horse to water, but you can't make him drink.
The philosopher, Bishop Berkeley, was concerned with creating his own philosophy of life. He realized that before he could go on creating a philosophy, he had to start with the fundamental ingredient of his own existence. His proof was simple, but irrefutable. Since I can think about the question at all, my thinking about the question proves my existence. Once Berkeley proved his existence he could do something about it. He made himself the center of his own universe, he became his own source of motivation. 
You, too, must become the source of your own motivation for all your bodybuilding endeavors. Take the word "can't" out of your training vocabulary and replace it with the word "will". Say to yourself, "I think therefore I am, I will therefore I can."
Spend 10-15 minutes "psyching" yourself up before your workout. Go over each exercise in your mind taking mental note of the exact exercise performance you will use. Each workout should be a performance and each performance must be more productive than the last. Imagine your goals to be at the top of a stairway and insure that after each workout, you can honestly take one giant step forward and upward.

Steve DavisSteve Davis - IFBB Mr. World 1977 - competed at the highest level during the Golden Era of bodybuilding. Steve appeared on the cover of 7 bodybuilding magazines. He trained closely with Vince Gironda for 3 decades. More bio

Raw Muscularity, by Steve Davis

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