As a former swimmer and coder, I understand exactly what you're talking about. Whenever I was in excellent shape, code would just flow from my fingers. I think it had to do with the fact that my body and mind were in sync.

Recently, I won the Ohio State Championships for Magic, the Gathering. I'd been close before, but the change was that I decided there was no option but to win. I wanted it so bad I could taste it, and I didn't allow myself any distractions. Before, being in the Top 8 would rattle me, but I didn't allow for that to happen this time.

What does that have to do with coding? Well, if you're constantly distracted or thinking about what is going on around you, then you won't be able to concentrate on what you're doing. That applies to both coding and swimming.

What I used to do before meets was to try and enter a slight meditative overlay, almost a mild auto-hypnosis. That would help me retain my calm and focus. Then, right before I entered the pool, I would shift out of that and start getting myself pumped up. This would allow me to go from a rested state to an active state very quickly and efficiently.

Don't worry about not doing well your first few meets. I remember a football player joining the team in college to keep fit during the off-season. He sucked. But, he kept at it and became a valued member of the team by the end of the year. Swimming is arguably the hardest sport to excel in at the lower levels, because it's the most alien sport for humans. Keep at it, and welcome to the best sport in the world. :-)

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We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.