How Marathon Training Increases Achilles Tendinopathy Risk: What Recreational Runners Need to Know

Achilles tendinopathy represents one of the most challenging running injuries, affecting approximately one in every twenty recreational runners. This painful condition, characterized by swelling, stiffness, and reduced Achilles tendon performance, can derail training and significantly impact a runner's quality of life.

A new comprehensive study has revealed important insights about Achilles tendinopathy occurrence patterns and risk factors, providing valuable guidance for recreational runners about preventive strategies.

Research Findings

A breakthrough study followed 2,378 recreational runners who participated in Dutch running events from 5 kilometers to full marathons. During the study period, researchers identified a 5.2% overall incidence rate of Achilles tendinopathy – meaning approximately 1 in 20 runners develop this condition.

However, risk dramatically varied depending on event type:

⚠️ Marathon runners: Highest risk with 7.4% incidence rate of Achilles tendinopathy

⚠️ Peak occurrence: In the two weeks before and immediately after running events

⚠️ Reason: Increased training demands, higher weekly mileage, and greater mechanical stress

Key Identified Risk Factors

1. Previous Injury (Most Important Predictor): The most significant predictor of Achilles tendinopathy development was experiencing this condition in the previous 12 months. Runners with a history of Achilles problems showed dramatically increased risk for recurrence.

2. Gender: Male runners showed higher susceptibility to Achilles tendinopathy compared to female runners.

3. Structured Training Schedules: Surprisingly, research identified that overly rigid training approaches can increase injury risk. Runners should maintain some flexibility in their training.

4. Compression Sock Findings:

Research showed a surprising finding: compression sock use was associated with higher Achilles tendinopathy risk in this population.

Important clarification: This does NOT mean compression socks are harmful. Researchers cautioned that compression users may represent a different runner population:

• May already be experiencing symptoms
• May be engaged in more intensive training
• May be using compression as a response to pre-existing issues

This is likely correlation, not causation – people with existing issues may use compression socks as part of their management strategy.

Practical Applications for Runners

✓ For runners with previous Achilles issues:

• Be especially careful with gradual return to training
• May benefit from professional guidance for recurrence prevention
• Complete recovery and proper rehabilitation are crucial

✓ For marathon runners:

• Pay special attention to Achilles tendon health
• Include appropriate strength training
• Flexibility work
• Gradual mileage increases

✓ For all runners:

• Maintain flexibility in training
• Listen to your body
• Adjust intensity or volume at early warning signs

Preventive Strategies

Gradual progression: Especially important for runners transitioning to longer race distances

Strength training: Targeted at calf muscles and Achilles tendon

• Eccentric strengthening exercises have shown particular promise

Recovery and load management:

• Research showed peak injury occurrence around major running events
• Combination of intensive training and race participation creates high-risk periods

Conclusion

For recreational runners, this research provides several actionable insights for preventing Achilles tendinopathy. Highest risks belong to marathon runners and those with previous Achilles issues, requiring special attention during preparation and recovery.

If you use compression socks, be mindful of proper fit, appropriate compression levels, and watch for developing symptoms. The key is monitoring how your body responds to any training intervention.

About the Research:

This research was conducted by Lagas, Fokkema, Verhaar, Bierma-Zeinstra, van Middelkoop, and de Vos, who examined incidence rates and risk factors for Achilles tendinopathy development in a large cohort of recreational runners.