Force-Velocity Profiling among Different Maturational Stages in Young Soccer Players: A Cross-Sectional Study

Abstract

Speed is a key component of football performance. An individualized approach may be necessary to achieve optimal speed development. Force-velocity profiling breaks down linear sprint performance into force, velocity, and mechanical effectiveness on an individual basis. In young footballers, these factors are related to maturation and have a strong influence on physical performance. The aim of this study is to investigate horizontal force-velocity profiling at different stages of maturation.

As an indicator of maturity, the age of peak height velocity (APHV) of 85 young soccer players (age: M = 15.7, ± 1.63 years) was determined using the Mirwald formula. According to temporal distance from their individual estimated APHV, players were divided into four groups (mid-peak-height-velocity (PHV, N = 26); 1-2y-post-PHV (N = 21); 2-3y-post-PHV (N = 21); >3y-post-PHV (N = 17)). 30-meter sprint performance including five split times was measured with timing gates in all athletes. These splits were used to calculate an individual horizontal force-velocity profile with its components maximum theoretical force (F_H0), velocity (V_H0), and power (P_max). These profiles also included peak ratio of force (RF_max), actual relationship of maximum force and velocity (FV slope), as well as the theoretically optimal relationship of maximum force/velocity (FV_opt).

APHV-based group differences were found for F_H0, V_H0 and P_max, RF_max, and the difference between FV slope and FVopt. Values of absolute F_H0, V_H0, RF_max and P_max were increasing with maturation. In all groups, a lack of velocity in relation to force production of 24% (p < .001, d = 1.15) was detected, with the largest deficit at mid-PHV (M = 35.74 ± 21.73%) and the smallest deficit at >3ypost-PHV (M = 15.90 ± 20.15%).

The current finding of a velocity deficit in 30m-sprint performance of young soccer players suggests a need for velocity-oriented training - pronounced around APHV.