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While they live next door to muscles, tendons (the structures that attach muscles to bones) differ in their response to injury. It’s not the same as their next-door neighbor’s aka muscles. In this blog post I’ll explain the make-up of a tendon, one of the main causes of tendon pain and what you can do about it.
What is a tendon made up of?
Collagen
Tendons are made up of well-organized collagen fibres (type 1 to be precise). Collagen is a protein. Picture steel wires neatly bundled together, super strong and very capable of resisting “tensile loading” strain basically.
Ground substance
Next enveloping the tendon is a, well let’s call it a “glue” called “ground substance.” This substance keeps it all together, composed of cells that are hydrophilic (attract water) called proteoglycans among others drawing water into the tendon.
What happens when a tendon gets injured?
Chances are your tendon pain didn’t suddenly come on in the same way you feel immediate pain when you pull a muscle. Tendon injuries often stem from overuse/overload that creeps up on you. Tendons take their time telling you if they’re unhappy or not. The way tendons react to overuse/overload is not the same way muscles heal when they’re injured. While a muscle strain will have an inflammatory phase, muscle fibres then regenerate and repair tendons don’t behave the same way.
1.“Puffer Fish”
First things to react are those water-loving cells, proteoglycans. Excessive loading (plus a combination of individual risk factors etc) will activate these cells. The number of those water loving cells increases and they start to balloon up from sucking more water in to the tendon. This is what causes tendons to thicken and swell (but notice I’ve not said “get inflamed” because there isn’t any inflammation).
2.“Ship Gets Flooded”
Ground substance starts to increase flooding the tendon
3.“Pirates are Scattered”
If the overuse/overload continues all these puffer fish onboard the ship start disorganizing your crew as they take up more and more room
4.“New Recruits”
Think of the type I collagen I mentioned earlier as your “highest quality pirate.” Well in the interest of urgency, your body starts lowering the bar and recruiting type III collagen, the bottom of the barrel type. It’s thinner and less resilient than type I collagen. So all in all, a flooded ship with a poor quality crew is a shipwreck. The tendon is disrupted and less capable of dealing with stress, absorbing forces and releasing them without pain.
5.“The Kraken Tentacles”
With your pirate crew disorganized it creates a chance for “neovascularization” the growth of new vessels to creep their way onto the ship (these vessels are theorized to be a cause of tendon pain)
“Can I keep training or do I need to rest?”
It’s the wrong question to ask because you’ll just get the black or white response i.e. either rest completely and tendon gets weaker, ignore and tendon keeps getting worse.
There is a phrase which I think sums up the answer nicely:
“The Poison is The Medicine”
Let me explain. It’s either a sudden spike in overuse or a gradual overuse, excessive loading lets say which has caused the problem, DOSAGE is what stops medicine being lethal and providing therapeutic effect. So just as your GP would prescribe a very specific dosage with medication, the same is true when correctly dosing exercise.
“What is the best way to load my tendon to get it better?”
So it’s not a question of “to load or not to load” it’s a question of “what’s the optimal loading strategy.”
Good thing I’ve got another blog post to answer exactly that question 😉
