This week we discuss tendon stress and strain. This article was a review written by one author which was published in 2022. We found the definitions provided in the article to be particularly helpful. Strain is the change in tendon length relative to normal length, while stress is the amount of force relative to the tendon (force/CSA). These describe what is happening to a tendon. Stiffness and Young's modulus are physiologic properties of a tendon. Stiffness is a change in tendon length relative to the force applied which is dependent on cross sectional area (CSA). Young's modulus is the relationship between stress and strain, which is independent of CSA (stress/strain). This review discusses a few different articles, but one of the key points we took from this is that you can increase strain on a tendon by using heavier loads or by working at a stretched position of the joint. While this review focuses on healthy populations, this could be applied to injured populations when treating patients with tendinopathy. If the goal is to try to induce tendon strain, you could explore a variety of loading options.

The abstract can be found here: https://pubmed.ncbi.nlm.nih.gov/36135039/

As always, if you enjoy what you hear, be sure to follow us on your favorite podcast platform and on Instagram @readingrehabpod. If you have any article recommendations be sure to send them our way!

Data Nerds is a new series that we are introducing which will be alternating weeks with our usual journal club podcast. In this series, we share cases from our clinical practice where we utilize objective testing to inform our decision making, with most attention paid to the results of the tests and interpretation of the information. Therefore, this works best when you can see the numbers. Luckily, these are uploaded to our YouTube channel! Check us out at https://www.youtube.com/@ReadingRehab.

This is a continuation of the case from Episode 1: Isometric testing. You can find that episode on our YouTube channel.

Since IE, Pat has been utilizing CPM mode for eccentric training of knee extension to both qualitatively and quantitatively improve his patients torque production capabilities throughout challenging ranges of motion.

The graphs demonstrate the progression his patient has made across 4 treatment sessions. We do not attribute this success to this sole intervention, but believe it is a great adjunct to track qualitative force production and provides a good stimulus along the way.

Pat discusses his rationale for modifying the exercise procotol and answers questions provided by Mike and Bryan.

This week we discuss knee and shoulder isokinetic torque strength targets among healthy athletes. This study had a sample of 233 athletes from 27 different sports! This is a little worrisome in that there is not a large sample for any one sport. They even grouped sports up into six different categoies, but there was still not enough data per category. Lumping sports could also be problematic because basketball and baseball are both team sports, but they have very different kinetic and strength requirements. The large standard deviations for knee torque are likely due to the variety of sports tested. So what can we take away from this? Across a variety of sports, it is standard to have above 3.0 Nm/kg knee extension torque, and at least 1.8 Nm/kg knee flexion torque. There is a strong correlation between peak torque and rate of force development. Shoulder external rotation and internal rotation peak torques are similar across two different speeds.

The abstract can be found here: https://www.jospt.org/doi/10.2519/josptopen.2025.0095

As always, if you enjoy what you hear, be sure to follow us on your favorite podcast platform and on Instagram @readingrehabpod. If you have any article recommendations be sure to send them our way!