If you’ve been struggling with surfer’s elbow (medial elbow pain), chances are your wrist and finger flexors are doing most of the work. Every paddle stroke, every pop-up, and every time you grip your board, these flexor muscles on the inside of your forearm are activated. Over time, they can become overloaded—especially if the muscles on the other side of your forearm aren’t pulling their weight.

That’s where the wrist and finger extensors come in.

The Balance Between Flexors and Extensors
Think of your forearm like a seesaw. On one side you have the flexors (the muscles that close your fist, pull your wrist down, and help you grip). On the other side you have the extensors (the muscles that open your hand, lift your wrist, and stabilize your grip).

If the flexors dominate, the seesaw tips one way. That imbalance puts extra stress through the tendon attachments on the inside of your elbow—the exact spot that flares up with surfer’s elbow. Training the extensors helps restore balance, keeping the seesaw level and your elbow healthier.

Why Extensor Training Helps Elbow Pain
– Load sharing: Strong extensors take pressure off the flexors, reducing overload at the tendon (Chaler et al., 2025).
– Grip endurance: Balanced muscles mean you can paddle longer without fatigue setting in.
– Joint stability: Extensors help stabilize the wrist and elbow during dynamic surf movements (Takeda et al., 2025).
– Injury prevention: A more balanced forearm reduces the risk of recurring flare-ups.

What the Research Says
Scientific studies have shown that muscular imbalance—specifically, stronger wrist flexors compared to extensorsc an predict relapse in chronic elbow pain (Chaler et al., 2025). Clinicians often use flexor–extensor strength ratios in their assessments, as these measures help guide tailored rehabilitation (Chaler et al., 2025).

Other research highlights how forearm position affects loading: in pronation, extensor activity increases, while in supination, flexor activation dominates (Takeda et al., 2025). This means grip work in different forearm positions is essential to address all aspects of tendon stress.

Finally, eccentric exercises, where muscles lengthen under load are a cornerstone of tendon rehabilitation. They stimulate tendon remodelling and restore load tolerance (JS Performance Lab, 2023).

How This Translates Into Rehab
Because of this evidence, I’ve built my 12-week surfer’s elbow rehab program to include:
– Both flexion and extension strengthening for true balance.
– A variety of gripping exercises in pronated and supinated positions to mimic the demands of paddling and board handling.
– Evidence-based eccentric loading strategies to promote tendon recovery.

This approach ensures clients train both sides of the seesaw so the flexors and extensors share the load, protect the elbow, and build resilience for time in the water.

Takeaway: Training your wrist and finger extensors isn’t just about adding strength it’s about restoring balance. By giving these often-overlooked muscles some attention, you can support your paddling, protect your elbows, and spend more time in the surf doing what you love.

References (APA 7th edition)

Chaler, J., De La Fuente, C., & colleagues. (2025). Strength ratios and relapse prediction in chronic elbow pain: An isokinetic study. Journal of Shoulder and Elbow Surgery. https://www.sciencedirect.com/science/article/pii/S1360859225002177

Takeda, Y., Nakagawa, T., & colleagues. (2025). Forearm rotation influences wrist flexor and extensor muscle activity: An EMG analysis. Journal of Orthopaedic Surgery and Research, 20(1), 1–10. https://josr-online.biomedcentral.com/articles/10.1186/s13018-024-05363-x

JS Performance Lab. (2023). Understanding epicondyle tendinitis: Causes and eccentric loading for recovery. Retrieved from https://www.jsperformancelab.com/blog/understanding-epicondyle-tendinitis-causes-and-eccentric-loading-for-recovery