Players will experience puberty during this stage, leading to physical, mental, and social development at varying rates. Training programs should be tailored to accommodate individuals who are early, average, or late in their maturation. For instance, a player may be 14 years old but could be physically comparable to an 11-year-old (late developer) or a 17-year-old (early developer). 

Physical maturity does not necessarily correlate with social or mental maturity. It is crucial to regulate training and playing time during puberty to avoid overuse, injuries, and hindered development. As players' skills and game understanding improve, there is a greater emphasis on tactical development. Physical training concentrates on enhancing strength, power, and speed.

Following puberty, anaerobic endurance training becomes more important, aiding players in recovering between high-intensity sprints or play periods. The training focus remains on development: while players naturally want to win, the emphasis should be on individual progress rather than team success.