Eccentric Hamstring Strength and Hamstring Injury Risk in Australian Footballers

Abstract

Low levels of eccentric hamstring strength increased the risk of future HSI. Interaction effects suggest that the additional risk of future HSI associated with advancing age or previous injury was mitigated by higher levels of eccentric hamstring strength.

Changes in agonist neural drive, hypertrophy and pre-training strength all contribute to the individual strength gains after resistance training

“…Muscular strength, the maximum force or torque a muscle group can produce, is a major contributor to function in both athletic (Wisloff et al 2004) and day-to-day tasks (Samuel et al 2012), and is a risk factor for muscle injury (Opar et al 2015) as well as the development (Slemenda et al 1998) and progression (Amin et al 2009) of joint degeneration in osteoarthritis. Consequently, resistance training (RT) is frequently employed when aiming to: improve athletic performance (Wilson et al 1996;Comfort et al 2012); enhance mobility of middle-aged and older adults (Brochu et al 2002;Brandon et al 2003); reduce injury risk (Brooks et al 2006;Noyes and Barber Westin 2012); prevent or slow the progression of joint degeneration (Zhang and Jordan 2010).…”

ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION & THE HAMSTRINGS Implications for injury prevention & rehabilitation

“…Meanwhile, athletes with a history of ACL injury or HSI display similar eccentric knee flexor weakness and shorter BFLongHead fascicle lengths in previously injured limbs compared to the uninjured contralateral limbs (Opar et al, 2015a;Timmins et al, 2016b). These findings suggest that a prior ACL injury and HSI may both significantly increase the risk of future HSI.…”

“…Previous work has shown that deficits in eccentric knee flexor strength during the performance of the Nordic hamstring exercise are associated with a 4.3 to 4.4-fold increased risk of future hamstring injury in elite Australian rules footballers (Opar et al, 2015a) and professional soccer players (Timmins et al, 2016b), although no such relationship was noted for Rugby players (Bourne et al, 2015). Meanwhile, athletes with a history of ACL injury or HSI display similar eccentric knee flexor weakness and shorter BFLongHead fascicle lengths in previously injured limbs compared to the uninjured contralateral limbs (Opar et al, 2015a;Timmins et al, 2016b).…”

“…The proposed mechanisms for HSIs include kicking, tackling, cutting, stooping while running and excessive stretching (Brooks et al, 2006;Ekstrand & Gillquist, 1983;Verrall, Slavotinek, Barnes, & Fon, 2003;Woods et al, 2004). However, the majority of HSIs in running based sports occur during high-speed activities (Bourne, Opar, Williams, & Shield, 2015;Brooks et al, 2006;Opar et al, 2015a;Timmins et al, 2016b;Woods et al, 2004).…”

“…For example, elite Australian footballers older than 23 years are at a heightened risk of HSI if they display low levels of eccentric knee flexor strength, but the effects of age are significantly smaller in stronger players (Opar et al, 2015a;Timmins et al, 2016b). More recently, Timmins and colleagues (2016b) found that higher levels of eccentric knee flexor strength and longer BFLongHead fascicles reduced the risk of HSI in older elite soccer players.…”