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

After ACL reconstruction, one open question is what type of strength training best restores leg power and jumping ability before athletes return to team sports. This randomised trial compared 6 weeks of eccentric-oriented flywheel training against traditional strength training in 22 professional team sport athletes (11 per group) already in the late-stage rehab phase after ACL reconstruction with a BTB graft, alongside the same overall rehabilitation program. Both groups improved over time on all measures tested, including isometric squat strength, vertical jump, single-leg jump and hop tests. However, the flywheel group showed significantly larger improvements than the traditional training group on several measures, including isometric strength in both legs, standard vertical jump, and single-leg jump and hop performance in the injured leg, with effect sizes described as large to very large.

The study was small, and details on blinding, adherence, and longer-term outcomes such as re-injury or actual return to play were not reported in the abstract.

If you've had ACL reconstruction surgery, one big question during recovery is which strengthening exercises help you get your leg power and jumping ability back fastest. This study looked at 22 professional team sport athletes in the later stage of their ACL rehab, split into two groups of 11.

One group did flywheel training, a method that emphasizes the lengthening phase of a muscle contraction, while the other did standard strength training, both alongside the same overall rehab program for 6 weeks. Everyone improved over the six weeks, which makes sense since they were all still recovering. But the flywheel group showed bigger improvements in leg strength, jumping height, and hop distances on the injured leg compared to the traditional training group. This was a small study of only 22 people, and it did not report whether these differences translated into safer or faster actual return to sport, or whether injury rates differed between groups.

The findings are promising for this type of training but need confirmation in larger studies before broader conclusions can be drawn.

This is a summary of research, not medical advice. Talk to your own healthcare provider about anything affecting your care.

This RCT compared 6 weeks of flywheel-based eccentric-oriented strength training against traditional strength training in 22 professional team sport athletes (11 per arm, mixed sex) undergoing late-stage ACL rehabilitation after BTB graft reconstruction, with both groups receiving an otherwise equivalent rehabilitation protocol. Outcomes included isometric semi-squat strength, countermovement jump, single-leg jump, single-leg hop, and triple hop tests, plus limb symmetry indices. Both groups improved over time across all outcomes, but significant group-by-time interactions favored the flywheel group for isometric strength in both injured and uninjured legs, CMJ, and injured-leg single jump, single hop, and triple hop performance, with reported effect sizes ranging from large to very large.

Limb symmetry index outcomes were calculated but interaction results for these specific indices were not detailed in the abstract. The sample size is small for each arm, and the abstract does not report blinding procedures, adherence data, or longer-term functional outcomes such as return-to-sport timing or re-injury rates. These findings suggest a between-group difference in intermediate performance measures during rehabilitation, but do not establish whether this translates to safer or more successful return to sport, and replication in larger cohorts with clinical outcome tracking would strengthen confidence in the effect.