The Relationship between Preseason Common Screening Tests to Identify Inter-Limb Asymmetries in High-Level Senior and Professional Soccer Players

Abstract

This study sought to examine inter-limb asymmetries in common screening tests performed during preseason and to analyze the relationship between the performance in the different tests. Nineteen high-level senior and professional soccer players (age: 23.2 ± 3.1 years; height: 181 ± 0.06 cm; body mass: 75.2 ± 4.8 kg) performed several common screening tests during preseason: Dorsiflexion lunge test (DLT); bent knee fall out test (BKFO); y-balance anterior test (YBT A); y-balance posterolateral test (YBT PL); Y-balance posteromedial test (YBT PM); Heel-rise test (HRT) and single leg hamstring bridge test (SLHBT). High levels of reliability (ICC > 0.88 and <0.94) were observed in all the studied variables. Inter-limb significant differences were observed in DLT and YBT PM test (p < 0.01) but YBT A, HRT and SLHBT presented trivial effect size (ES) (0.03; 0.07 and 0.13, respectively), contrary to DLT, BKFO and YBT PL, all with small ES (0.20; −0.23 and −0.22) and YBT PM, which revealed very large ES (2.91). Considering all data, high-level senior and professional soccer players present fairly good mean values of lower limb symmetry. Performance considering all tests was different, a fact associated with different biomechanical dynamics (e.g., YBT), nonetheless, the correlations between tests underline the relationship between these, which could represent important evidence to consider for injury prevention and performance enhancement programs.

Lower Limb Unilateral and Bilateral Strength Asymmetry in High-Level Male Senior and Professional Football Players

“…Thus, from a practical applications perspective, it seems prudent to suggest that strength training should be considered in high-level male senior and professional football players, as recently suggested for football academy players [73,74]. Finally, football club structures (in concrete, some of those associated with decision making regarding daily training conditions) should assume that collaborative work developed by professionals of different areas is a plus for athlete's global condition and may represent an important support in the definition of evaluation procedures, specifically protocols aiming to improve injury prevention and, at the same time, to improve sports performance [18].…”

“…A minimum symmetry target of 10% has been previously suggested for evaluation and rehabilitation protocols [16], being equally considered for clearance to return to practice after anterior cruciate ligament reconstruction (ACLR) [17]. Lower limb injuries are a serious issue in professional athletes because they may be associated with long-term absence from match and health-related problems and related to decreased performance and financial costs [18]. On average, for example, typical hamstring strain injuries causes athletes to miss 2 weeks of training or competitive play [19], with this timeline potentially representing up to 6 fixtures being missed, with professional football teams often experiencing 5-6 hamstring injuries per season [5].…”

Relationship between Femur Mineral Content and Local Muscle Strength and Mass

“…For example, the involvement of boys and young adults in specific sport training regimens, such as soccer, without an appropriate monitoring of the healthy progression of players’ conditioning level has increased the occurrence of injuries, most frequently compromising soft tissues, with the possibility to exacerbate impairments on both physical and technical levels [ 17 ]. In this sense, regular training monitoring is vital, and the collaborative work developed by professionals from different areas such as sports sciences, physiotherapy, and biomedical technology may represent an important support for the detection and prevention of injuries and, at the same time, improve sports performance without compromising tissue integrity [ 18 ].…”