Growth until Peak Height Velocity Occurs Rapidly in Early Maturing Adolescent Boys.

The timing and tempo of growth rate varies inter-individually during adolescence and can have an impact on athletic performance. This study aimed to determine the difference in growth rate for each maturity status. We combined data collected both retrospectively and prospectively from 78 adolescent boys aged 12 years old; growth charts were collected from their elementary school records, and the height of each participant was subsequently measured every six months over a period of two years. Take Off Age (TOA), Peak Height Velocity Age (PHVA), and Final Height Age (FHA) were estimated using the AUXAL 3.1 program. Growth Tempo 1 and 2 were calculated by dividing the height increase by the time difference between TOA and PHVA, and FHA, respectively. Our results showed three group differences based on the maturation status of PHVA: Growth Tempo 1 and 2 were both higher in the early than during middle and late maturation. Additionally, entering the height at each event as a covariate, the group differences for Growth Tempo 1 did not change; however, for Growth Tempo 2, group differences were eliminated. Therefore, we conclude that during early maturation, growth from TOA to PHVA occurs rapidly and in a shorter period.