The Use of the Functional H:Q Ratio to Assess Fatigue in Soccer

Abstract

The aim of this study was to investigate the effects of fatigue induced by a field test representative of soccer specific movements on different hamstrings:quadriceps ratios in the dominant and non-dominant legs at two different velocities. Eight male football players (age: 21.3+/-2.3 years; height: 178+/-8 cm; body mass: 78+/-9 kg; playing level: British University Southern conference-3B) performed a pre-test to assess the concentric and eccentric strength of the hamstrings and the quadriceps at 60 degrees x s(-1) and 180 degrees x s(-1), The Loughborough Intermittent Shuttle Test (LIST) to simulate soccer, and a post-test similar to the pre-test. The main findings demonstrated significant decreases in the H(con):Q(con) ratio (calculated as the maximal concentric hamstrings strength divided by the maximal concentric quadriceps strength) in the dominant leg at 180 degrees x s(-1) and in the functional ratio H(ecc):Q(con) (calculated as the maximal eccentric hamstrings strength divided by the maximal concentric quadriceps strength) in the dominant leg at 60 degrees x s(-1) and 180 degrees x s(-1). In addition, significant correlations were observed between physiological parameters measured during the soccer-specific exercise and H(ecc):Q(con) only. These results suggested that the functional H(ecc):Q(con) ratio is more representative of fatigue induced by soccer than the conventional H(con):Q(con) ratio. Eccentric strength training at high velocities may be necessary to reduce injury risk in soccer players.

Changes in Isokinetic Muscle Strength in Adolescent Soccer Players after 10 Weeks of Pre-Season Training

“…It is possible that the high volume of soccer-specific training included a lot of kicking exercises and the DL (i.e. kicking leg) was more accustomed to rapid eccentric actions in the hamstrings in order to slow the movement of leg during the followthrough of repetitive kicking actions [20,48]. Thus, the increase in the H:Q FUNC of the DL seems beneficial, as an increase in the antagonistic eccentric hamstring activation may act as a natural protective mechanism because it reduces unnecessary tension of the anterior cruciate ligament [49,50].…”

Effects of treadmill versus overground soccer match simulations on biomechanical markers of anterior cruciate ligament injury risk in side cutting

“…Together, these findings lead to a speculation that exertion induced by match duration may contribute to injury related to decreased muscle strength (Delextrat, Gregory, & Cohen, 2010;Greig, 2008;Small, McNaughton, Greig, & Lovell, 2010) and altered movement mechanics (Greig, 2009;Sanna & O'Connor, 2008;Small, McNaughton, Greig, Lohkamp, & Lovell, 2009). …”

Hamstring Muscle Fatigue and Central Motor Output during a Simulated Soccer Match

“…Muscular fatigue is often identified as a risk factor linked to the high incidence of hamstring strain injuries observed across all levels of soccer [4]–[6], with injury typically observed in the latter stages of training and each half of competitive matches [1]–[3]. Studies have reported reductions in knee flexor maximal torque during and after actual and simulated soccer match play [7]–[10], with reductions most pronounced in the latter stages of each half [8], [10]. No study has examined whether hamstring fatigue during soccer is mediated by peripheral or central mechanisms.…”