Eccentric Training: Strech Less, Train Smart, Move Better!

A common belief in the Sports Industry is the “Lift heavy, get stiff” way of thinking. 

But recent research is actually challenging this belief. The correct type of eccentric-only training, increases strength, improves flexibility and decreases Passive Muscle Stiffness over time (1).  The catch is, understanding that short-term effects differ from long-term adaptations. 

PASSIVE MUSCLE STIFFNESS

One important measure of how muscles respond mechanically to stretching without active contraction is the Passive Muscle Stiffness.It’s your body’s natural resistance to stretch - like how easy or hard it is to bend your knee when you’re fully relaxed (1). The stiffer the muscle, the more effort it takes to move it. One could think of it as “built in tightness” that muscles have, even at rest. Traditionally, static stretching has been used to reduce this stiffness. However, emerging research suggests that eccentric resistance training may also be an effective — and potentially more functional — way to improve this aspect of mobility.

SHORT-TERM SORENESS VS LONG-TERM FREEDOM

Eccentric training is focused on the lengthening phase of a movement, e.g. slowly lowering during a deadlift, or performing exercises such as nordic curls. It’s well-known for triggering Delayed Onset Muscle Soreness (DOMS) due to the micro-damage it causes to muscle fibers.

In the short term, eccentric training does in fact increase muscle soreness and can cause temporary stiffness (4). Past studies have shown that muscles showed greater muscle stiffness and muscle damage, after performing eccentric rather than concentric movements (4).

STRENGTH & FLEXIBILITY ARE NOT OPPOSITES

A surprising takeaway from recent research is that the separation with strength and flexibility in training is not needed. It was believed for decades that lifting weights only makes us stiffer, but eccentric training actually shows a different story.  By controlling the lowering phase of a movement, a powerful stimulus can be created and it increases both strength and flexibility (2). In a study involving dancers training, eccentric training led to improvements in hamstring flexibility and strength (2). Dancers are a group that already requires a high demand of flexibility, this proves even highly flexible individuals can benefit from this approach (2).

NOT ALL MUSCLES REACT THE SAME

The effectiveness of eccentric training varies by muscle group. Different muscles have different structural properties and baseline stiffness levels (5). Hamstrings tend to be more prone to stiffness and injuries, which makes them a prime target for eccentric work. Additionally muscles like the trapezius, calves and quads can also benefit from it (5).

However, in the example of the hamstrings, it was shown that different hamstring heads can respond differently to eccentric loads, which reinforces that exercise selection, execution and volume can influence the results (3). Professional football clubs are increasingly integrating eccentric exercises like the Nordic Hamstring Curl in their training routines to protect against injuries and build strength. A study by Oliveira et al. (2020), showed that implementing a four-week Nordic Hamstring program during preseason significantly increased eccentric knee flexor strength in u20 players from a Brazilian first division club. This highlights how eccentric-focused work is not only effective in theory but it is also practical and feasible within the demanding schedules of elite football environments (6).

HOW TO USE IT

• Slow the lowering phase: Perform the eccentric portion of each exercise slowly, around 3-6 seconds to maximize muscle adaptation.

• Use full range of motion: Train through a full, controlled range to improve flexibility and reduce stiffness.

• Train 2-3 times per week: Include eccentric focused movements two to three times weekly for consistent long-term results.

• Start light, build gradually: Begin with lighter loads to reduce excessive soreness and increase intensity over time.

  • Target Specific Areas: Focus on commonly stiff or injury prone muscles like hamstrings, glutes, calves, & upper back.

KEY TAKEAWAYS

• Eccentric training is more than just a strength tool, if used correctly it can reduce passive muscle stiffness and improve flexibility over time. 

• In the short term, soreness is normal, it is a part of the long-term adaptation that leads to better muscle compliance, resilience, and control.

• Strength and flexibility are not mutually exclusive, eccentric movements offer a practical way to train both simultaneously.

• How you train matters, slow tempo, full range of motion, and consistent frequency are critical for meaningful results.

• This approach challenges the outdated belief that lifting makes you stiff, and offers a smarter, more efficient alternative to endless stretching routines.

Bibliography

Kawama, R., et al. (2024). Can Eccentric-Only Resistance Training Decrease Passive Muscle Stiffness while Increasing Size and Strength of Hamstrings? Medicine & Science in Sports & Exercise.

Zeng, Y., et al. (2023). The Effects of Eccentric Training on Hamstring Flexibility and Strength in Dancers. Scientific Reports.

Šarabon, K., et al. (2022). The Effects of Eccentric Exercise on Passive Hamstring Muscle Stiffness. Journal of Physical Therapy Science.

Hubal, D. M., & Rubinstein, H. K. (1999). The Role of Passive Muscle Stiffness in Symptoms of Exercise-Induced Muscle Damage. The American Journal of Sports Medicine.

Madeleine, N., & Voigt, M. (2020). Eccentric Exercise Reduces Upper Trapezius Muscle Stiffness. Frontiers in Bioengineering and Biotechnology.

Oliveira, N. T. de, et al. (2020). A four-week training program with the Nordic hamstring exercise during preseason increases eccentric strength of male soccer players. International Journal of Sports Physical Therapy.