Athlete's knee glowing with energy during eccentric exercise.

ACL Recovery: Can Eccentric Training Be Your Secret Weapon?

Reese Marlowe in Health & Wellness November 2025 • 4 min read.

"Discover how eccentric exercises can significantly enhance strength and function after ACL reconstruction, getting you back in the game faster!"

Anterior cruciate ligament (ACL) injuries are a common setback for athletes and active individuals. Reconstruction surgery is often the first step, but the journey to full recovery requires a comprehensive rehabilitation program. Traditionally, rehabilitation focuses on regaining strength and stability through various exercises. However, one specific type of training, known as eccentric training, is gaining recognition for its potential to maximize recovery outcomes.

Eccentric training involves exercises where the muscle lengthens while under tension. Think of slowly lowering a heavy weight during a bicep curl – that's the eccentric phase. This type of training has been shown to be particularly effective at building strength and improving muscle function. The research article "CORRELATION BETWEEN ECCENTRIC TRAINING AND FUNCTIONAL TESTS IN SUBJECTS WITH RECONSTRUCTED ACL" dives deep into eccentric training and jump tests and they are widely used to recover and measure deficits in knee strength and functionality after anterior cruciate ligament (ACL) reconstruction.

This article aims to translate the research into practical insights. We will explore how eccentric training can be a game-changer in your ACL recovery, bridging the gap between scientific findings and real-world application for a stronger, more functional knee.

Unlocking the Power of Eccentric Training

Athlete's knee glowing with energy during eccentric exercise.

The study, featured in the article "CORRELATION BETWEEN ECCENTRIC TRAINING AND FUNCTIONAL TESTS IN SUBJECTS WITH RECONSTRUCTED ACL", investigated the impact of eccentric isokinetic training on individuals who had undergone ACL reconstruction. Sixteen male subjects with unilateral ACL reconstruction were assessed before and after a 12-week eccentric isokinetic training program. This program focused on strengthening the knee flexors and extensors, using controlled movements at specific speeds.

The training involved performing eccentric exercises at 30°/s (degrees per second) for both extension and flexion. Researchers measured peak torque (MPT), which indicates the maximum force a muscle can generate, and compared the results with functional jump tests like single, triple, cross, and figure-of-8 hops. These tests are designed to assess overall lower limb function and agility, crucial for returning to sports and daily activities.

Increased Torque: The affected limb showed significant gains in both extension and flexion torque across various test categories and speeds.
Improved Jump Performance: Participants saw an increase in jump distance (single and triple hops) and a decrease in completion time (crossed and figure-8 hops).
Specificity Matters: The most significant gains were observed in the training mode and speed (Ecc_30°/s), highlighting the principle of specificity in exercise.
Neural Adaptations: The non-affected limb also showed gains, potentially due to the crossover education effect, where unilateral training benefits the opposite limb.

While the study confirmed that eccentric training leads to improved knee strength and jump performance, the correlation between torque and jump performance was not as strong as expected. This suggests that knee functionality involves other factors beyond just muscle strength, such as motor control and coordination. Therefore, a comprehensive rehab plan should address these aspects.

The Takeaway: A Holistic Approach to ACL Rehab

While eccentric training offers significant benefits for ACL recovery, it's essential to remember that it's just one piece of the puzzle. A successful rehabilitation program should incorporate a variety of exercises to address strength, motor control, balance, and proprioception. Always consult with a physical therapist or sports medicine professional to develop a personalized plan that meets your specific needs and goals. With the right approach, you can return to your favorite activities with a stronger, more resilient knee.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1590/1517-869220182406184218, Alternate LINK

Title: Correlation Between Eccentric Training And Functional Tests In Subjects With Reconstructed Acl

Subject: Physical Therapy, Sports Therapy and Rehabilitation

Journal: Revista Brasileira de Medicina do Esporte

Publisher: FapUNIFESP (SciELO)

Authors: Heleodório Honorato Santos, Catarina De Oliveira Sousa, Christiane Lanatovitz Prado Medeiros, José Angelo Barela, Ana Maria Forti Barela, Tania De Fatima Salvini

Published: 2018-12-01

Everything You Need To Know

What exactly is eccentric training, and how does it specifically aid in ACL recovery?

Eccentric training focuses on lengthening a muscle while it's under tension, like slowly lowering a weight during a bicep curl. In the context of ACL recovery, eccentric exercises for the knee flexors and extensors can significantly improve muscle strength (peak torque) and functionality. This type of training is valuable because it builds strength and enhances how the muscles function during movement, contributing to better rehabilitation outcomes after ACL reconstruction.

According to the "CORRELATION BETWEEN ECCENTRIC TRAINING AND FUNCTIONAL TESTS IN SUBJECTS WITH RECONSTRUCTED ACL" study, what were the key improvements observed after implementing eccentric training?

The study "CORRELATION BETWEEN ECCENTRIC TRAINING AND FUNCTIONAL TESTS IN SUBJECTS WITH RECONSTRUCTED ACL" showed that eccentric training led to increased peak torque in both extension and flexion of the affected limb. Participants also showed improvements in functional jump tests, such as single and triple hops (distance increased) and crossed and figure-8 hops (completion time decreased). Importantly, the specificity principle was highlighted, meaning the most significant gains were seen in the trained mode and speed (Ecc_30°/s). This indicated that the benefits were closely tied to the specific type of exercise performed.

If eccentric training is so effective, why did the study mention that the correlation between torque and jump performance wasn't as strong as expected? What does this imply for ACL rehab?

While eccentric training improves knee strength and jump performance, the study found that the correlation between torque and jump performance wasn't as strong as expected. This suggests that factors beyond muscle strength, like motor control and coordination, also influence knee functionality. Therefore, a comprehensive ACL rehabilitation program should address these additional aspects to ensure a well-rounded recovery. Addressing motor control and coordination could involve balance exercises, agility drills, and proprioceptive training.

What is the 'crossover education effect' mentioned in relation to the study's findings, and how does it relate to ACL recovery?

The "crossover education effect" refers to the phenomenon where training one limb (unilateral training) can lead to strength gains in the opposite, untrained limb. In the study, even the non-affected limb showed gains, suggesting that eccentric training not only benefits the operated knee but also provides some benefit to the non-operated knee through neural adaptations. This effect underscores the interconnectedness of the nervous system and how training one side of the body can influence the other.

Besides eccentric training, what other components are essential for a comprehensive ACL rehabilitation program, and why is a holistic approach so important?

To maximize recovery outcomes after ACL reconstruction, incorporate a holistic approach that combines various exercises. This includes eccentric training to improve strength and function, but also exercises to address motor control, balance, and proprioception. Consulting with a physical therapist or sports medicine professional is crucial. They can develop a personalized plan tailored to individual needs and goals, ensuring a safe and effective return to activities. Without considering all factors like balance, there is an increased risk of re-injury.