Athletes of all shapes and sizes need to become powerful. If you are a distance runner you should squat!!! If you are a sprinter you should do stability work and have great general strength. The best athletes are those who have a body in balance. However, to get enough training across all the biomotor abilities requires a huge commitment from both coach and athlete in terms of time. I also believe the athlete must surrender their talent to the coach. Surrender of talent must happen before an athlete can truly make gains long term under their coach.