sprinting and achilles

Sprint Smart: Tending to your Achilles Tendons

At Primal Speed, we promote the myriad of benefits of sprinting and power work because we want people to experience a higher quality of life, enabling them to perform their desired physical activities with vim and vigor. But we would be remiss to ignore the injury risk that exists with ballistic and high-effort activities such as sprinting.

Every physical activity presents the body with potential benefits and drawbacks, and sprinting is no different. Besides the obvious risk of muscle strains, overload to tendons is a common occurrence. This is especially true for the middle-aged and older individuals out there who desire to keep higher levels of speed and power as they age.

Of all the tendons in the lower body that are at risk for becoming irritated and overloaded from sprinting, it is the Achilles tendon that most frequently succumbs to conditions such as tendinopathy (aka “tendinitis”).

Other tendons that are at risk are the patellar tendon, the gluteal tendons, and even the plantar fascia, which behaves similarly to the other mentioned tendons when overloaded.

Tendons 101


Since tendons connect muscles to bones, they help to transmit forces from muscular contractions so that movement can occur. The lower extremity tendons, especially the Achilles tendon, also behave like a spring and help to store and release elastic energy to make movements like walking, running, and especially jumping and sprinting, more efficient.

This storage and release of elastic and mechanical energy has also been called the “stretch-shortening cycle,” or “SSC” in the scientific literature. Unfortunately, when too much of this type of loading is performed or too high of an intensity occurs, a tendon can get overloaded, strained, and injured. The most graphic example of overload is tendon failure, or rupture.

Tendon Overload

When tendons get overworked, they can go into what’s termed “reactive tendinopathy.” The tendon becomes sore and painful, perhaps even a bit swollen.

Despite what appears to be an inflamed area, reactive and cranky tendons don’t have a significant inflammatory process going on; therefore, researchers and clinicians have been moving away from the term “tendinitis” since inflammation, although present, is not the primary driver of the condition.

The major culprit in irritating a tendon such as the Achilles tendon for example, is the adage “too much too soon.”

With sprinting, the foot hits the ground on the forefoot (ball of foot) and this puts large forces through the metatarsal heads, the plantar fascia, and the gastroc-soleus-Achilles tendon complex.

If the force or the volume of the foot strikes exceeds the capacity of the tendon, it can get irritated. Additionally, doing too much hill work, being overweight, having diabetes or blood sugar regulation issues, hyperlipidemia, and even taking certain antibiotics (floriquinilones) can all increase the risk of tendon overload and injury.

However, since pain in the region of a tendon can be coming from a more serious cause, it’s always important to check with a competent health care professional such a physical therapist, athletic trainer, sports medicine physician, or podiatrist before trying to treat something like this on your own.

The Bottom Line and Key Take-Aways


The bottom line is that tendons are “change-phobic,” meaning they do not like large fluctuations in volume and intensity of loading. The key is to find the appropriate amount of continuous loading that promotes the biological adaptations we are looking for, but without overloading the tendon and causing a reactive and painful tendinopathic type of condition.

This is why my brother and I can be found saying that sprinting and plyometrics are like playing with fire; it’s easy to get burned if you’re not careful! Thus, a little can often go a long way.

When learning to perform true alactic (without lactate) types of sprints (less than 6-7 seconds), it can be euphoric, a feeling we like to call the “sprinter’s high.” This is similar but different to the well-known “runners high.”

This euphoric feeling can cause many sprinting enthusiasts, especially the middle aged and more “seasoned” ones, to overdo it, thinking that they’re back in high school again reliving their glory days!

This can lead to a subsequent stirring up of their Achilles tendons or other muscle strains and pulls such as the ubiquitous hamstring “pull” that plagues many weekend warriors. With respect to tendons, once they get flared up, the pain, stiffness, and inhibition of muscle function can last for weeks to months. It absolutely sucks.

In an upcoming article, some tips and suggestions will be given on how to incorporate the powerful and euphoric drills and skills of primal speed sprinting, but with a common-sense approach to volume, intensity, and progression. When approached rationally, sprinting and power work (jumps, throws, skips, etc.) can be weaved into a health and wellness-approach to life-long fitness and athletic development (intentional athleticism).

In speed, strength, and health,

Keats Snideman

Trackback from your site.

Keats Snideman

Keats Snideman is a health and fitness-promotion specialist and owner of the Reality-Based Fitness, a Training Center in Tempe, AZ. He specializes in evidence and science-based strength & conditioning and soft-tissue therapies. His hobby and passion is in the development and maintenance of speed, strength, and dynamic mobility as the human body ages.

Leave a comment

You must be logged in to post a comment.