Running injuries: focus on the knee joint
In this second article about running-related injuries, we will focus on the knee joint.
This anatomical area is usually the one that most frequently causes problems for our runners, both professional athletes and amateurs. First, we need to distinguish the type of injury: in most cases, it is not a traumatic event (for example, knee sprains with ligament or meniscal injuries), but rather “overuse” injuries. This term refers to a category of problems related to overload (whether articular, muscular, or capsulo-ligamentous).
At the root of overuse injuries is, as the term implies, an imbalance between the load capacity of a given structure and the amount of work we subject that structure to; in simpler terms, we train too much without adequate recovery.
Within this second category of injuries, we can mention three musculoskeletal conditions that most commonly affect our runners:
1. Patellofemoral syndrome: this term refers to various issues involving the joint between the posterior surface of the patella and the femoral trochlea. Both excessive patellar mobility and excessive compression of the patella on the femoral groove can cause localized pain in the anterior knee and the retro-patellar area.
2. Iliotibial band syndrome: it seems to be caused by excessive compression of a highly vascularized and innervated fat pad located between the iliotibial band and the lateral femoral epicondyle, resulting in pain on the lateral side of the knee.
3. Patellar tendinopathy: this is a condition affecting the patellar tendon, the structure that connects the lower pole of the patella to the tibial tuberosity, causing pain just below the patella.
Unlike traumatic injuries, which force the athlete to suddenly stop practicing sports, overuse injuries develop gradually and progressively, initially presenting as mild pain that does not limit running, and later becoming more persistent both during training and at rest; symptom duration can range from a few weeks to several months.
Since each individual needs to be assessed individually, our recommendation is to rely on a professional who can design a rehabilitation program based on your needs and critical issues, rather than following exercise protocols found online and standardized for the general population. For these reasons, in this article, it does not seem appropriate to go into detail on how to “heal” and “resolve” the above-mentioned problems; however, with the help of scientific literature, we can look at the risk factors that may make a person more or less prone to developing certain musculoskeletal conditions and propose preventive exercises to minimize the incidence of these types of injuries.
The main risk factors, or contributing factors, for the onset of knee joint pain are:
- Reduced hip and ankle mobility: two predisposing factors that could lead to knee joint overload are, specifically, limited hip extension and limited ankle dorsiflexion. As suggested in the previous article, instead of performing passive stretching exercises as a pre-run warm-up, we recommend joint mobility exercises, focusing on the joints that feel more “stiff” or “blocked.” Here are two exercises for hip and ankle: perform the movements slowly and continuously for about 1 minute. The first mobilizes both hip joints in extension, moving from the first image position (hips flexed) to the second image position (hips extended). The second exercise mobilizes the ankle in closed-chain dorsiflexion: from a lunge position, with hands pressing above the knee, try to reduce the angle between the leg and the foot while moving the knee forward. It is important that the foot remains fully in contact with the ground; repeat the movement rhythmically for about one minute.
- Reduced strength of the hip abductors, quadriceps, and hamstrings: weak hip abductor muscles lead to what is called “dynamic valgus,” i.e., the inward collapse of the knee during exercises involving this joint, increasing compressive and shear forces on all joint structures. Similarly, strong quadriceps and hamstrings allow for more efficient force generation and absorption during running. Therefore, it is recommended for every runner to integrate, alongside running training, two weekly sessions of lower limb strengthening exercises. Three basic exercises that should never be omitted for knee health prevention are: squats, lunges, and single-leg bridges, possibly with additional weights such as dumbbells or kettlebells, performing 3 sets of 8-12 repetitions for each exercise.
- Poor training programming: as mentioned in the previous article, one of the most important factors to prevent various injuries is proper training planning. For amateur runners, we recommend always leaving 1–2 rest days between runs, and after any break longer than two weeks (for reasons such as work, injury, lack of time, etc.), a gradual return-to-run phase should be implemented, avoiding resuming the previous pace and distance immediately. These are preventive exercise suggestions for healthy individuals, based on the most common risk factors for knee problems in runners. Each person should be assessed individually, and a safe return-to-run program should be developed together with the individual.
The knee is undoubtedly one of the most stressed areas during running, and therefore also one of the most vulnerable. But it is not the only one. If you want to learn more about other areas prone to injury in runners, we recommend reading the articles dedicated to the ankle and foot and muscle injuries and tibial stress syndrome:
