All About Your Tendons


It’s Monday morning after an exhausting weekend full of your favorite activities. The 7:00 a.m. alarm sounds, you jump out of bed ready to take on the week and…ouch! Sore joints. It seems you may have overdone it. The culprit may have been the company softball game Saturday morning or perhaps it was the intense CrossFit workout at the local box later that afternoon. Come to think of it, it was probably running the impromptu 10k on Sunday, particularly given the fact that you didn’t warm up beforehand!

We have all been there — doing more physical activity than our body is accustomed to and then later paying the price. Commonly, this is the mechanism that causes mild injuries, or strains, to our tendons. Tendons are the tissues that connect your muscles to your bones to help control how your limbs move. They are like thick, strong, elastic bands that function in a manner similar to a spring. In fact, they are so strong you can suspend 12 times your body weight from your Achilles tendon.

Tendons are composed of tiny repeating units of elastic collagen proteins. When we over work our tendons, it results in microtrauma to this collagenous substructure, leading to a buildup of inflammation. Typically, your joints will feel stiff and tender to the touch around the body of the tendon. Normally, with rest, it is possible to recover from light strains in about a week. Resuming high-impact activities too soon can turn a small setback into a big one. So whether it’s your shoulder, knee, or ankle, don’t rush it.

Tendons heal much more slowly than muscle tissue, making it tempting to get back at it prematurely. The danger here is when you begin continually loading your tendons despite the fact that they haven’t fully recovered at a structural level. Initially, any pain is easy to manage with ice and ibuprofen.  Over time, however, you may become accustomed to the discomfort to the point where it feels normal. This type of chronic pain around a tendon is called tendonitis and indicates a pathological state of under recovery. The tendon tissue is struggling to keep up and has essentially done a rough patch job on itself, rendering it weaker and less elastic.


The slow degradation and change in the collagen composition of the tendon increases the risk of one of the most brutal injuries in sport — the full tendon rupture. Even with millions of dollars of financial interest in preserving their health, some of the world’s best athletes have fallen victim to this season-ending injury. The most common area to injure is the Achilles tendon. You need to look no further than major league sports such as the NBA to see the impact of this brutal injury. With the punishing game schedule and the volatile nature of the sport, the strain placed on connective tissues is immense. Stars including Dominique Wilkins, Kobe Bryant, DeMarcus Cousins, Rudy Gay, and many others have suffered through Achilles ruptures. For many, their careers never got back on track post injury.   

What are the Risk Factors?

The risk of an injury is the product of interactions between intrinsic risk factors and extrinsic risk factors. The former are elements innate or internal to the body. These are often heavily influenced by your genetic makeup. Extrinsic risk factors represent environmental inputs that place stress on your body, joints, and muscles. These factors are in our control by way of the choices we make every day. Knowing the internal state of your body, or injury predisposition, will help you make better decisions in managing your injury susceptibility. If you participate in a sport or activity that is high impact, high velocity, and involves repetitive movement, developing a preventative mindset could be key in preserving your long-term health. Up next, we will highlight three areas that are important to consider if your goal is to reduce injury risk.

Injury Graphic

Program Design & Monitoring   

Often times, chronic tendon injuries are the product of poorly designed training programs. The stress placed on the body becomes maladaptive, leading to injury over time. Here are two steps to ensure your programming doesn’t end up giving you flat tires.


Periodization, at its core, means to plan your training out in advance in a thoughtful manner. Two first principles to keep in mind here are that of loading variation and recovery residuals. The former posits that in order for our bodies to adapt to training we need variation in loading. This doesn’t mean you have to switch it up all the time, but it does mean that if you did the identical workout routine over and over again for months on end, not only would you get very bored but you’d also likely get hurt due to the chronic repetitive strain on your tissues. This is partially why overuse injuries like tendonitis tend to be common in athletes as they are putting in many more reps of very similar movement patterns than those in the general population.

In the second principle, planning recovery is a crucial aspect of your training, whether you are a recreational or professional athlete. Every workout you complete has a residual recovery period attached to it. The length of this residual is highly specific to the intensity, fitness level, and type of the work performed. As far as your tendon health is concerned, high-impact activities like sprinting, jumping, cutting, and decelerating demand the greatest recovery time. Ideally, after performing 60-90 minutes of these intensive exercises you wouldn’t repeat them for roughly 72 hours.  

Monitoring with Training Load

Working out entails putting your body through an arbitrary amount of physical stress. You can never be completely sure how your body will respond due to the multitude of influencing factors at play. The old adage “listen to your body” couldn’t be truer. A simple and valid method to measure and quantify the internal stress your body is under is to keep a training journal. In your journal, you should calculate and record your daily training load (TL). TL is calculated by multiplying the difficulty of the day’s workout — measured on a scale of very easy (1) to very difficult (10) — by the total time spent working out (in minutes). By plotting this value over time you should observe peaks, valleys, and trends. When your TL remains moderately high for long periods of time, your risk for injury will increase dramatically.

The Genetic Factors  

The contraction and relaxation cycles that occur during movement stimulate growth within the collagen matrix of tendons. This process is complex. However, scientists have identified many of the key genes involved in conducting this regenerative process.      

Researchers have found that variations in how tendons respond to strain and how your cells repair tendons are linked to your DNA. Athletigen’s Optimum Movement and Recovery Report contains analyses of five genes that have variants associated with the risk of tendon pathologies. Each of these genes has its own special role within the tissue maintenance and regeneration process.  

Specifically, the matrix metalloproteinase-3 (MMP3) gene helps create enzymes that break down excess damaged tissue. Essentially, these are the waste collectors being sent into the tendon to ensure that non-functional debris is cleared away after collagen homeostasis has been disrupted.

Vascular endothelial growth factor A (VEGFA) is involved in the regulation of blood vessels around tendons. While tendons are predominantly an avascular tissue, after microtrauma blood vessels begin to proliferate around the tissue, bringing the nutrients required for its repair.

Tendons are largely made up of type-1 collagen. The 5A1, 1A1, and 12A1 collagen genes all encode for structural sub-units within the type-1 collagen tissue. Some variants of these genes may negatively affect the manner in which tissue is rebuilt, leaving it less elastic and more prone to re-injury.    

Some athletes are able to “genetically buffer” poor technique for long periods of time without injury, while others succumb to their poor mechanics quickly and get hurt. Regardless, it makes sense to address sloppy mechanics — if not to prevent injury, then to increase the efficiency of your performance.

Preventative Care

Soft-tissue therapy is the cornerstone of injury prevention. Tendons like going through uniform ranges of motion so they can stretch and recoil in an elastic, spring-like manner. Poor mechanics can result in excessive shear and twisting forces that unduly stress the tissue. Because of this, it’s worth ensuring you keep the mobility of your joints in check so you can support perfect technique and loading patterns. Massage and trigger-point therapy are the mainstay for physiotherapists when they work with athletes. However, most of us aren’t lucky enough to have a personal therapist. Enter MobilityWOD and Dr. Kelly Starrett — the king of DIY therapy. Below are several effective techniques to help maintain function in areas susceptible to tendonitis.  

Lower Body Mobility Maintenance

Did you know that tight quadriceps and calves can increase the risk of patellar and Achilles tendonitis, respectively?



Upper Body Mobility Maintenance

If you train overhead frequently or participate in throwing sports you’ll want to get this in 2-3 times per week!


Interested in learning more about how your genetics influence your tendon health? Check out Athletigen’s Optimum Movement and Recovery Report. You’ll find information on 70+ genetic markers related to injury prevention, exercise recovery, sleep performance, and more. It also contains 40+ hours of video content featuring our partner M|WOD and Dr. Kelly Starrett, making this the ultimate package to keep you healthy now and going forward!



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