A novel device to assess hip strength: Concurrent validity and normative values in male athletes

Adductor Muscles Strength and Strength Asymmetry as Risk Factors for Groin Injuries among Professional Soccer Players: A Prospective Study

“…Given that the position of the dynamometer (externally fixed in the current study vs. handheld in the study by Mosler et al [17]) and the normalization procedure were similar in both studies, and considering the phenomenon of bilateral strength deficit [31], these findings suggest that the manual handling of the dynamometer could underestimate player's true adductor strength. Related to that, O'Brien et al [27] recently reported that only 40-50% of the common variance exists between adductor strength measured with a handheld dynamometer and an externally fixed dynamometer similar to the one used in the current study. While our prospective study is not the first one that used an externally fixed dynamometer for testing soccer players' adductor strength at the ankle level [13], no previous study has related this type of adductor strength measure with groin injury risk in soccer.…”

“…After a standardized warm-up (running 5 min at a comfortable pace, 2 min of dynamic stretching, 2 min of skipping and footwork drills, 10 body-weight squats, 10 sit-ups, 10 forward lunges, 5 short sprint accelerations, and 1 set of three 5-second submaximal ball squeezes with the feet), players performed bilateral isometric hip adductor strength testing using externally fixed dynamometry (Figure 1), similar to the one recently described by Bourne et al [13] and O'Brien et al [27]. In brief, players were required to lie in a supine position with their knees and hips fully extended.…”

Strength development and non‐contact lower limb injury in academy footballers across age groups

“…Isometric hip ADD strength and ABD strength were assessed using the Force Frame (Vald Performance Albion, Australia). This device has previously reported moderate‐to‐good correlations (0.53 to 0.71) against current practice devices in football players 10 and high reliability (CV = 6.6% 11 ). Players first adopted a standardized position, where they lay in a supine position.…”

“…In an effort to account for significantly different body weights, as seen in youth athletes of a wide age range, allometric scaling of all assessed strength variables was employed 15 . It is possible that the practical arrangements required to allow the testing of a large cohort might have provided some players with insufficient recovery periods between maximal contractions, but the protocols are consistent with past research 10‐12 . Our study was also unable to include training and match exposure, or training load data, limiting our knowledge of the transient increases in competition/training volume/intensity and their impact on strength levels and injuries in academy football.…”

“…Force data for the right and left ADD and ABD exercises were measured from force transducers sampling at 50Hz. Isometric hip strength was determined for each leg from the peak force during the best of three repetitions of 5 seconds of ADD and ABD, 11 each repetition was separated by a period of 10 seconds 10 …”