oa Muscle Mechanical Determinants of Sprint Performance Across the Professional Life-Span in Soccer Players

Background: The functional relevance of strength and power measures as an index of functional performance (i.e., sprinting speed) in soccer remains unclear.

Objective: The aim of this study was to investigate the relationships among mechanical variables related to strength and power tests and their influences on sprinting speed in professional soccer players across their life-span.

Methods: Isokinetic measures (quadriceps (Q) peak torques and power at 60°/s and 300°/s), kinetic outputs of the counter-movement jump (CMJ), and sprinting speed (the first 5 m split time (i.e., initial speed) and the 15 to 20 m split time (i.e., leading sprint) of a 20 m sprint), were measured in 224 professional soccer players (age 23.7 ± 4.4 y, body mass 71.4±8.8 kg and height 1.75±0.06 m).

Results: The values for each variable for the fast and slow groups are displayed in Table 1. All the mechanical variables were significantly different between the fast and slow players regardless of the results were ranked according to 5 m or 15–20 m times. The results of the multiple regression analyses identified CMJ height as the best predictor of sprinting performance for the 5 m (R=0.39, P=0.000) and 15–20 m (R=0.51, P=0.000) sprint.

Conclusions: All the mechanical variables could discriminate between the fast and slow players. However, a great degree of unexplained variance still remains indicating there may be better mechanical predictors of sprinting speed in soccer players.