Ability of Countermovement Jumps to Detect Bilateral Asymmetry in Hip and Knee Strength in Elite Youth Soccer Players

Abstract

Clinicians frequently assess asymmetry in strength, flexibility, and performance characteristics as a method of screening for potential musculoskeletal injury. The identification of asymmetry in countermovement jumps may be an ideal method to reveal asymmetry in other lower extremity characteristics such as strength that otherwise may require additional testing, potentially reducing the time and burden on both the athlete and clinicians. The present study aims to examine the ability of asymmetry in both the single-leg and two-leg countermovement jump tests to accurately detect hip abduction, hip adduction, and eccentric hamstring strength asymmetry. Fifty-eight young male elite soccer players from the same professional academy performed a full battery of functional performance tests which included an assessment of hip adductor and abductor strength profiles, eccentric hamstring strength profiles, and neuromuscular performance and asymmetries during countermovement jumps. Bilateral variables attained from both the single-leg and two-leg countermovement jump tests included concentric impulse (Ns), eccentric mean force (N), and concentric mean force (N) computed by the VALD ForceDecks software. Average maximal force (N) was calculated bilaterally for the strength assessments. Asymmetry was calculated for each variable using 100 × |(right leg − left leg)/(right leg)| and grouped into three categories: 0 to <10%, 10% to <20%, and 20% or greater. Analyses were performed for the two higher asymmetry groups. The accuracy to detect strength asymmetry was assessed as the sensitivity, specificity, and predictive values for positive and negative tests. The outcomes from the accuracy assessments suggest that the single-leg countermovement jump concentric impulse variable at the 20% threshold is indicative of a youth male soccer player having hip adduction strength asymmetry while also demonstrating more accuracy and applicability than the two-leg countermovement jump concentric impulse variable.

Long Jump Performance Is Not Related to Inter-Limb Asymmetry in Force Application in Isometric and Vertical Jump Tests

“…The same was observed in the present study. In general, the assessment of the mechanical performance and, in particular, the examination of maximal force is effective for the study of inter-limb asymmetries due to its high reliability [21,25]. In addition, the results showed that the h JUMP did not differ between the unilateral vertical jump tests.…”

“…The evaluation of the specific strength and power of track and field jumpers using common laboratory tests provide information about their fitness level, their performance capacity, and the inter-limb asymmetry in these factors. These tests are the squat jump (SQJ) and the countermovement jump (CMJ) with and without an arm swing, executed bipedal or unilaterally [19][20][21]. Despite the fact that the isometric muscle contraction is different than the function of the acting muscles during sport movements, isometric [22] and isokinetic [23] tests have been suggested as well.…”

“…From the above-mentioned tests, those who evaluate the effectiveness of the stretch-shortening cycle with regard to the force-length relationship of the muscular actions in the LJ are suggested to be related to LJ performance [24]. Furthermore, unilateral vertical jump tests are suggested to monitor the specific strength parameters [20], as well as to evaluate the inter-limb asymmetry in force application and its effect on the jumping ability [21]. Due to the higher observed reliability in the assessment of inter-limb asymmetry, the force application recorded in the unilateral CMJ is suggested to be the parameter of interest [25].…”

Jumps and Lower Limb Strength Asymmetry in Young Soccer Players: Differences Between Sand and Conventional Surfaces

“…Therefore, not only the type of exercise but also the duration of training loads on sand must be carefully considered to prevent fatigue from increasing the interlimb asymmetry value (Guan et al, 2021;Wrona et al, 2023).…”

Pedagogical control scales of vertical jumping performance in untrained adolescents (13–16 years): research by strata

“…The improvement of basic physical skills is one of the essential contents addressed by the physical activity sciences and sport, including other applied disciplines such as medical sciences ( Wrona et al, 2023 ; Sagarra-Romero et al, 2017 ), being also a component managed by the pedagogy that is part of the evaluation of the educational process ( Herrmann et al, 2019 ), which provides interpretable and useful results for making the right decisions to optimize the teaching process ( Natriello, 1987 ).…”