Maybe even if you don't make it, you'd look back fondly on your time as a competitor as a formative period. I'm sure you'd gain lots of skills by having such discipline and rigor.
I did not learn any discipline because everything was scheduled for me. I really didn't like most of my experience.
Two positives:
1. I kept a lot my agility, muscle, and flexibility. Even after ceasing all physical activity for over 10 years.
2. Sharpened the connection between my mind and body. I'm really good at learning new physical skills that require fine motor control.
Though I'm sure many, many other activities can provide these benefits as well.
If I could go back, I would spend less time in those tennis camps, less time playing WoW, and more time in shop class, and hanging with the robotics people.