Effects of Eccentric-Oriented Strength Training on Return to Sport Criteria in Late-Stage Anterior Cruciate Ligament (ACL)-Reconstructed Professional Team Sport Players

Abstract

Background and Objectives: An effective post-injury training program is essential to regain performance and fulfill criteria for return to sport for team sport athletes following anterior cruciate ligament (ACL) reconstruction. The aim of this study was to compare the effects of 6 weeks of eccentric-oriented strength training vs. traditional strength training during the late-stage ACL-rehab phase on leg strength and vertical and horizontal jumping performance in professional team sport athletes. Materials and Methods: Twenty-two subjects (14 males, 8 females, age 19.9 ± 4.4 years, mass 77.4 ± 15.6 kg, height 182.4 ± 11.7 cm) (mean ± SD) with a unilateral reconstructed ACL (BTB graft) were included in the study. All participants enrolled in the same rehabilitation protocol prior to the training study. Players were randomly assigned to an experimental (ECC: n = 11, age 21.8 ± 4.6 years, mass 82.7 ± 16.6 kg, height 185.4 ± 12.2 cm), and a control group (CON: n = 11, age 19.1 ± 2.1 years, mass 76.6 ± 16.5 kg, height 182.5 ± 10.2 cm). Both groups underwent an equivolumed rehabilitation program, with the only difference being in strength training, which consisted of flywheel training vs. traditional strength training for the experimental and control groups, respectively. Testing was organized before and after the 6-week training programs and included isometric semi-squat tests (ISOSI-injured and ISOSU-uninjured legs), vertical jump tests (CMJ), single-leg vertical jump tests (SLJI-injured and SLJU-uninjured legs), single-leg hop tests (SLHI-injured and SLHU-uninjured legs), and triple hop tests (TLHI-injured and TLHU-uninjured legs). In addition, limb symmetry indexes were calculated for the isometric semi-squat (ISOSLSI) test, the single-leg vertical jump (SLJLSI), and the hop (SLHLSI) tests, as well as the triple-leg hop (THLLSI) test. Results: Main effects of time across training were observed for all dependent variables (posttest > pretest, p < 0.05). Significant group-by-time interactions were found for ISOSU (p < 0.05, ES = 2.51, very large), ISOSI (p < 0.05, ES = 1.78, large), CMJ (p < 0.05, ES = 2.23, very large), SLJI (p < 0.05, ES = 1.48, large), SLHI (p < 0.05, ES = 1.83, large), and TLHI (p < 0.05, ES = 1.83, large). Conclusions: This study suggests that eccentric-oriented strength training in late-stage ACL recovery, undertaken twice or three times weekly for 6 weeks, results in better outcomes than traditional strength training in leg strength, vertical jump ability, and single and triple hop tests with injured legs in professional team sport athletes. It seems that flywheel strength training can be recommended in late-stage ACL recovery for professional team sport athletes in order to regain recommended performance outcome levels faster.

Tubularization of Bone-Tendon-Bone Grafts: Effects on Mechanical Strength and Postoperative Knee Stability in Anterior Cruciate Ligament Reconstruction

“…The effectiveness of postoperative rehabilitation is critical for ensuring optimal outcomes following ACL reconstruction. According to a recent study, a 6-week eccentricoriented strength training during the late-stage ACL-rehab phase demonstrated superior leg strength and jump performance for professional team sport athletes compared to traditional strength training [47]. Such findings suggest that the integration of eccentric-oriented strength training, potentially coupled with the benefits of the tubularized graft, might offer a comprehensive approach to expedite recovery and return to sports.…”

Effect of Step Load Based on Time under Tension in Hypoxia on the ACL Pre-Operative Rehabilitation and Hormone Levels: A Case Study

“…Training with an extended eccentric phase may be a better option for recovery after ACL reconstruction because it provides improved lower limb strength and improved performance in various jump tests. Stojanovic et al [17] showed that a 6-week eccentric training programme produced a significantly greater improvement in lower limb strength than standard strength training. A longer duration of the eccentric phase has proven to be a good method of accelerating rehabilitation or PR as a result of ACL rupture due to unique neural patterns and increased mechanical muscle tension, which provides a better neuromuscular response to strength training.…”