Biological maturation rate and its relationship with physical fitness indicators in 14 year old youth soccer players

Individual differences in biological maturation constitute one of the key factors affecting the effectiveness of long-term athletic development in youth football. During adolescence, considerable variability in the rate of biological maturation limits the informative value of chronological age as the sole criterion for planning training loads and evaluating athletes’ physical capabilities. Consequently, the assessment of biological development has become an important component of individualized training strategies.Purpose. The purpose of this study was to determine the pace of biological development of 14-year-old football players using sensorimotor reaction indicators and to identify its relationship with physical fitness characteristics.Methods. Thirty male football players aged 14 years participated in the study. Sensorimotor reaction time was assessed using the Diagnost-1 hardware and software system according to the patented methodology for evaluating human sensorimotor reactivity. The pace of biological development was calculated as the ratio between the measured and age-standardized sensorimotor reaction values, while biological age was determined using the calculated biological development pace. Physical fitness was evaluated by means of the standing long jump, 30-m sprint with intermediate timing at 10 m and 20 m, the 7 × 30 m repeated sprint test, and the Illinois agility test. All running tests were performed using the Witty photoelectric timing system.Results. Considerable inter-individual variability in biological maturation was identified among football players of the same chronological age. Although the mean chronological age of the participants was 14.02 years, estimated biological age ranged from 11.0 to 16.2 years. Athletes with a normal pace of biological development accounted for 53.3% of the sample, whereas accelerated and delayed maturation groups each represented 23.3%. Comparative analysis demonstrated consistently superior physical fitness outcomes in the accelerated group across all performance tests. These athletes achieved better results in the standing long jump, sprint running, repeated sprint ability, and agility compared with players characterized by delayed biological maturation.Conclusions. The findings indicate that the pace of biological development determined from sensorimotor reaction indicators is closely associated with the level of physical fitness in young football players. The observed relationships support the validity of the sensorimotor approach for biological age assessment and confirm its practical value for optimizing individualized training programs according to athletes’ biological maturation rather than chronological age.