One of the biggest challenges in running is staying healthy through training progressions. It’s common to feel strong — but still be sidelined by tendon pain or overuse injuries. This comes down to a fundamental biological difference: muscles and tendons adapt at very different rates.
Muscles adapt quicker to strain and stress. As evident from strength and muscle size changes within weeks of resistance training. This is due in large part due to the blood supply muscles have.
Tendons on the other hand are slower to adapt. Tendons are largely made of collagen with relatively limited blood supply. This difference results in a more prolonged period for changes to occur.
This mismatch in adaptation timelines means that we build muscles faster than tendon strengthening.
What Research Tells Us About Tendons
- Tendon adaptation require longer, consistent loading. Systematic reviews show that changes in tendon stiffness are seen when resistance training programs exceed 12 weeks.
- Muscle strength can increase before tendon strengthening catches up. Often we have a period of time where muscle growth exceeds tendon growth, during this time frame injuries can develop.
- Patience pays off; While muscles can show notable changes in weeks, tendons require months of progressive heavy resistance training.
- The best way to develop tendon health is by doing some of the following exercises:
- Progressive strength training
- Isometric loading
- Gradual progression
- Balance active loading and recovery appropriately
Summary
It is crucial that athletes, in particular runners invest in appropriate resistance training to promote tendon stiffness and resiliency. Running offseason can serve as the perfect opportunity to develop a regular routine to promote tendon health.