Avoiding Injury in Marathon Training: The Importance of Gradual Mileage Increases to Prevent Tendinopathy
- Gemma Extence
- Feb 14
- 5 min read
Recently, I’ve seen a lot of tendon pain in the clinic. Many runners, whether seasoned marathoners or newcomers, are dealing with tendinopathy—pain and irritation in their tendons, often in the Achilles, knees, or hips. One of the primary causes of tendinopathy in runners is increasing mileage too quickly during training. It’s easy to get caught up in the excitement of a training plan and push your body faster than it can adapt, but this can lead to painful injuries that derail your progress. In this post, we’ll dive into the importance of gradually increasing your mileage to prevent tendinopathy, the risks of terrain change, and how to stay injury-free throughout your marathon training.
1. Understanding Tendinopathy and Its Risks
Tendinopathy refers to the irritation or degeneration of a tendon, often caused by repetitive strain or overuse. For runners, tendinopathy typically affects the Achilles tendon, patellar tendon (in the knee), and the iliotibial (IT) band. When you run, your tendons absorb the shock of each stride, and when the intensity or volume of running increases too quickly, the tendons don’t have enough time to adapt to the increased load, leading to micro-tears and inflammation.
Tendinopathy is often a result of "training errors," such as suddenly ramping up your weekly mileage or increasing the intensity of runs without proper progression. The body needs time to strengthen and adjust to the physical demands of running, and skipping this gradual adaptation process can increase your risk of developing painful tendon injuries.
2. The 10% Rule: Gradual Mileage Increases
One of the key principles for avoiding tendinopathy is to increase your weekly mileage gradually. A well-established guideline for runners is the 10% rule, which recommends increasing your total weekly mileage by no more than 10% each week. This gradual progression allows your muscles, ligaments, and tendons to adapt to the increased workload without being overwhelmed.
For example, if you're running 30 miles in one week, the following week you should aim for no more than 33 miles. This incremental increase reduces the risk of overloading your tendons and muscles, giving them time to build the strength needed to handle higher volumes of running. By following this approach, you can maintain a steady, sustainable training load while minimizing the risk of injury.
3. Why Gradual Progression Matters
The body's tendons are designed to handle stress, but they do so gradually. When you increase your mileage too quickly, the tendons are not able to strengthen at the same pace as the muscles, leading to potential imbalances and increased strain. Tendons are slower to adapt than muscles, and a sudden jump in running distance forces them to absorb too much force too quickly, which can result in tendinopathy.
This is why gradual progression is key: it allows your tendons to build strength and elasticity over time, providing them with the capacity to handle more load without succumbing to injury.
Additionally, slow increases give you the opportunity to listen to your body and adjust your training if you feel any discomfort or signs of strain in the tendons.
4. Listen to Your Body and Adjust Accordingly
While following the 10% rule is a useful guideline, it’s also crucial to listen to your body. Every runner is different, and some people may need to progress at a slower pace based on their previous running experience, biomechanics, or injury history. If you experience any early signs of tendinopathy, such as localized pain or stiffness in your Achilles, knee, or hip tendons, it’s essential to reduce your mileage and allow for proper recovery.
Incorporating rest days and cross-training into your schedule will also help your body adjust without overloading the tendons. Cross-training activities like swimming, cycling, or strength training can help you maintain fitness while reducing the impact on your tendons, giving them a break from the repetitive motion of running.
5. The Impact of Terrain on Tendon Health
It’s not just about increasing mileage; the type of terrain you run on can significantly affect your tendons as well. Running on uneven or hilly terrain places different stresses on your body compared to running on flat roads. While varied terrain can be great for strengthening muscles and preventing boredom, it can also increase the risk of tendinopathy, especially if your tendons aren’t conditioned for the increased load.
Hills: Uphill running can put more strain on the calves and Achilles tendons as they work harder to propel you forward. On the other hand, running downhill places a greater load on the quadriceps and knees, which can increase stress on the patellar tendon and IT band. Sudden increases in hill running without proper adaptation can result in tendinopathy.
Uneven surfaces: Running on trails, dirt paths, or other uneven surfaces increases the risk of ankle sprains and overuse injuries to the tendons, especially if you are not accustomed to it. Your tendons need time to adjust to the varying surface types, which require additional stabilization.
To reduce the risk of tendinopathy caused by terrain change, it’s important to gradually introduce different surfaces into your training. If you’re used to running on the road, try incorporating trail runs or hill repeats into your routine slowly and with proper technique. Make sure to wear appropriate shoes that provide support for the type of terrain you're running on.
6. Strengthen Your Tendons to Prevent Injury
In addition to gradually increasing your mileage and adjusting to terrain, it’s important to include strength training in your marathon training routine to help prevent tendinopathy. Targeting key muscle groups, especially those around the hips, knees, and calves, can improve tendon health and function. Stronger muscles help absorb some of the impact forces during running, reducing the load on the tendons and lowering the risk of injury.
Focus on exercises that strengthen your glutes, quads, hamstrings, and calves, as these muscles work together with your tendons to stabilize your body during each stride. Eccentric exercises—where the muscle lengthens while under tension—are especially beneficial for tendon health, as they help promote tendon strengthening and repair.
7. Monitor Your Recovery and Adjust Your Training Load
Proper recovery is another key factor in preventing tendinopathy. When you increase your mileage or change terrains, it's just as important to give your body time to recover and adapt. Rest days and sleep are essential for tendon repair and overall injury prevention. Additionally, pay attention to other aspects of recovery, such as nutrition and hydration, to support the healing and strengthening of your tendons.
If you’re feeling fatigued, don’t be afraid to scale back your training for a few days. Running through pain or discomfort can worsen a developing tendinopathy issue, so it’s always better to err on the side of caution and allow your tendons adequate time to recover.
8. Incorporate Rest Weeks
Every few weeks, it’s wise to schedule a “down” week where you reduce your mileage by about 20-30%. This allows your body—especially your tendons—to recover and reset, reducing the risk of cumulative stress and injury. During these weeks, focus on maintaining fitness through lower-impact activities, and give your tendons time to fully recover before ramping up your mileage again.
Final Thoughts
Avoiding tendinopathy in marathon training comes down to one key principle: gradual progression. By increasing your mileage slowly, listening to your body, adjusting to changes in terrain, and incorporating strength training and rest, you can ensure that your tendons remain strong and resilient throughout your training. Remember, marathon training is a long-term process, and by building up your endurance and strength in a sustainable way, you’ll be able to stay injury-free and cross the finish line feeling strong.
Happy running, and take care of those tendons!
Comments