This is the second part of our tendon stiffness discussion. In the first post, found here https://petroskiphysio.com/ucl/ we discuss how tendons get stronger and why it is important. In this discussion we will discuss why it matters and how to achieve this tendon stiffness. For young pitchers and overhead athletes, UCL (ulnar collateral ligament) injuries can be game-changing, often requiring extensive rehab or even Tommy John surgery. At Petroski Physio, we prioritize the latest evidence-based practices to help athletes get healthy and perform at their peak. One of the most exciting topics we’ve recently explored is the role of tendon stiffness in protecting the UCL and improving overall performance.
This post will break down key takeaways from our team’s clinical discussion and continuing education on the subject. The discussion is originally based off a presentation given by Driveline’s Baseball Physical Therapist, Dr. Newman. Our team debated the presentation and used it to provide you with some actionable insight.
What Is Tendon Stiffness and Why Does It Matter?
To refresh, tendon stiffness refers to a tendon’s ability to resist deformation under stress. For pitchers, stiffer tendons in the forearm and shoulder can help reduce stress on the UCL, improve force transfer during throwing, and ultimately lower the risk of injury. Achieving optimal tendon stiffness involves targeted training methods, including isometric and eccentric exercises.
The Training Protocols That Build Resilient Tendons
Here are the top strategies our team discussed for increasing tendon stiffness and protecting the UCL:
- High-Intensity Isometric Holds
- Why? Sustained tension during isometric holds stimulates collagen cross-linking, leading to tendon remodeling and increased stiffness.
- How? Focus on exercises targeting the flexor digitorum superficialis (FDS), flexor digitorum profundus (FDP), and flexor carpi ulnaris (FCU)—key muscles that stabilize the UCL.
- Parameters:
- Hold each rep for 6–20 seconds.
- Use at least 70% of maximum voluntary contraction (MVC), scaling to 90–95% for shorter holds.
- Perform these exercises 2–4 times per week during training.
- Eccentric Loading
- Gradual lengthening of the muscles under load strengthens tendons and prepares them for the demands of throwing.
- Incorporate exercises like controlled wrist or forearm curls with resistance bands or light weights.
- Progressive Overload and Consistency
- Tendons adapt slowly—minimum measurable changes occur after three months of consistent training.
- Plan long-term conditioning blocks to allow sufficient time for tendon adaptation.
Early Injury Management and Safe Loading
When dealing with athletes recovering from UCL or other tendon injuries, the focus must shift to safe, low-intensity loading to avoid setbacks.
- Start with low-intensity, long-duration holds:
- Use 20–30% of MVC for 30–45 seconds to reduce fluid retention and stimulate collagen remodeling without aggravating the injury.
- Gradually increase intensity as pain subsides and tissue tolerance improves.
- Consistency prevents detraining effects: Incorporate low-load exercises daily or every other day to maintain progress even during rest phases.
Off-Season Training: The Key to Long-Term Success
The off-season is the perfect time to focus on tendon health. Here’s why:
- Tendons can benefit from a period of sustained loading without the stress of in-season competition.
- Building resilience during the off-season allows pitchers to handle higher throwing volumes during the season.
Athletes should view off-season training as an investment in their career longevity. Tendon stiffness gains protect their ability to perform long-term but require consistent effort over months to achieve meaningful results.
The Role of Education in Preventing UCL Injuries
Many athletes underestimate the importance of tendon health and the time required to see results. Here’s how we help bridge that gap:
- Educating athletes early:
- We explain the connection between forearm and shoulder strength, UCL protection, and overall performance.
- Empowering athletes with data:
- Regular assessments of grip strength, pronation/supination range, and UCL-specific metrics help track progress and fine-tune programs.
- Providing individualized programs:
- Exercises are tailored to specific pitching mechanics, such as the grip variations between fastballs and sliders, which engage different muscle groups.
Takeaways for Young Athletes
Preventing UCL injuries and improving tendon stiffness isn’t about quick fixes—it’s about consistent, intentional work. Whether you’re a high school pitcher or an aspiring pro, here are some actionable steps:
- Start incorporating isometric and eccentric forearm exercises into your routine.
- Commit to long-term training, especially during the off-season.
- Focus on quality over quantity—proper technique and intensity matter.
- Communicate with your coaches and trainers about any pain or discomfort.
By prioritizing tendon health and resilience, you’re not just reducing your risk of injury—you’re building a stronger foundation for success on the mound.
Optimize Off-Season Training for Tendon Health and Injury Prevention
At Petroski Physio, we’re dedicated to helping athletes reach their full potential through science-backed training and rehab. Tendon stiffness is just one piece of the puzzle, but it’s a critical one for protecting your UCL and elevating your game. Want to learn more about our individualized programs for pitchers? Contact us today to get started.