‘He’s Got Growth’: Coaches Understanding and Management of the Growth Spurt in Male Academy Football

The majority of studies investigating maturation in football have focused on the impact of maturity status or timing upon athletic performance. There is comparatively little research investigating the impact of the adolescent growth spurt, and few research articles that have focussed on injury incidence and burden rather than performance. The aim of this study was to explore and better understand how the adolescent growth spurt impacts youth football players within professional academies. This longitudinal mixed-methods study aimed to understand youth football coaches’ perceptions, experiences, and management of male adolescent football players. Players’ maturity status, growth velocities, and match performance were measured and interviews with coaches were conducted in parallel. The qualitative and quantitative data were combined to generate a deeper contextualised understanding. This study revealed that academy football coaches describe adolescent growth as a ‘condition’; players are diagnosed with growth through perceived signs and symptoms, which coaches must manage and treat. Growth was also seen to impact coaches’ perceptions and therefore had implications for selection and release decisions. The findings from this study emphasise the complexities of experiencing and managing adolescent growth and maturation in the context of elite youth football

Raw acceleration from wrist- and hip-worn accelerometers corresponds with mechanical loading in children and adolescents

This is the final version. Available on open access from MDPI via the DOI in this recordData Availability Statement: The data presented in this study are available on request from the corresponding author.The purpose of this study was to investigate associations between peak magnitudes of raw acceleration (g) from wrist- and hip-worn accelerometers and ground reaction force (GRF) variables in a large sample of children and adolescents. A total of 269 participants (127 boys, 142 girls; age: 12.3 ± 2.0 yr) performed walking, running, jumping (5 cm) and single-leg hopping on a force plate. A GENEActiv accelerometer was worn on the left wrist, and an Actigraph GT3X+ was worn on the right wrist and hip throughout. Mixed-effects linear regression was used to assess the relationships between peak magnitudes of raw acceleration and loading. Raw acceleration from both wrist and hip-worn accelerometers was strongly and significantly associated with loading (all p’s < 0.05). Body mass and maturity status (pre/post-PHV) were also significantly associated with loading, whereas age, sex and height were not identified as significant predictors. The final models for the GENEActiv wrist, Actigraph wrist and Actigraph hip explained 81.1%, 81.9% and 79.9% of the variation in loading, respectively. This study demonstrates that wrist- and hip-worn accelerometers that output raw acceleration are appropriate for use to monitor the loading exerted on the skeleton and are able to detect short bursts of high-intensity activity that are pertinent to bone health.Economic and Social Research Council (ESRC