As The Pro nailed a 15 foot putt for his par on the next green he continued talking about physical energy:

“So where does energy fit in? The more fit you are the more efficiently your body converts what you put into it into energy for performance. The key to making your body an efficient converter of food and oxygen into energy is exercise. Cardiovascular fitness helps you turn the air you breathe into immediate energy. It also is a key to being able to focus and concentrate. Research has shown that mental performance is significantly better in those who are physically fit. Fit people are better at complex decisions. They can sustain energy over the course of the day and are less prone to the kind of fatigue that steals away performance.”

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