Updated: Jun 20
Have you heard that tendons have a poor blood supply and that you have to increase the blood flow to your Achilles tendon to speed up its recovery? In this article, I explain why you don’t have to worry about stimulating the blood flow to your injured Achilles tendon and what you should do instead to make it heal quicker. Remember, if you need more help with an Achilles injury, you're welcome to consult one of our team via video call.
In this article:
We also made a video about this:
Low blood supply to tendons is normal
You may have heard or read that tendons have poor blood supply and that's why they heal so slowly.
Yes, tendons do have a poorer blood flow than, for example, muscles, but this is natural.
Muscles need lots of blood to supply them with the oxygen and energy they have to consume to contract and create the necessary forces to do their job.
Tendons have a different function; they anchor your muscles to your bones and act as “shock absorbers” (especially the Achilles tendon).
Also, an injured tendon does not have a poorer blood supply than a healthy tendon. In fact, if you examine a tendon with a tendinopathy under a microscope or with ultrasound, you'll see that actually it has more blood flow and blood vessels growing into it than an uninjured tendon has.
So it's important to understand that, while blood flow helps to explain why certain structures may heal slower than others, it does not mean that a tendon having less blood supply than muscles is abnormal or that increasing its blood flow will make it heal more quickly. That’s just the way it is with tendons!
Why increasing the blood flow to injured tendons is neither feasible nor useful
Some people might think: "Oh well, if the injured tendon has a poor blood supply, then the way to get it to heal better is to increase this blood flow, so let's do things to increase the blood flow."
A common way many people go about this is by applying heat to the injured tendon.
The body’s heat regulation system is pretty efficient. The body doesn't want any of its parts to get too hot, because it wants to avoid tissue damage.
So, your body has very good safety mechanisms in place to deal with external heat. As soon as you heat up that tendon area, the blood vessels in the skin will widen to get rid of the heat, and the heat won’t even reach the blood vessels in the tendon.
If you were heat that area excessively and you do actually manage to increase that tendon's temperature significantly, you can give yourself an additional injury – a heat injury.
So, don't get bogged down because you've read somewhere that the blood flow to the tendon isn't great and that you have to increase it to help the tendon heal. That's just normal tendons for you, and mentioning the low blood flow is just an explanation of why the healing process is slow. You can't increase that blood flow significantly enough through external interventions to speed up the healing process.
The best way to treat your Achilles tendon injury
The way to get better if you've got an Achilles tendinopathy is relative rest plus careful progressive loading with strength training.
No amount of blood flow will help that tendon recover if you're still overloading it by doing activities that it's not ready for.
However, relative rest doesn’t mean putting up your leg and doing nothing. It means that you only reduce or stop doing those things that irritate the injured tendon. If running, or walking, or jumping hurts, you have to stop or reduce it to a level that doesn’t cause an increase in your symptoms.
This article provides a full explanation of how to incorporate relative rest into your Achilles rehab.
When you injure your tendon, it loses some of its strength and endurance. The only way to regain that lost strength is with a strength training programme. If you don’t strengthen up your injured Achilles tendon, you might reinjure it as you start going about your normal business and doing your sporting activities again.
So, combined with the relative rest, you have to do careful strength training to renew and strengthen the collagen fibres that your Achilles tendon is made up of.
This doesn't mean that you should just go for broke with your strength training; the amount and intensity of the exercises have to be at the right level for you and for what your Achilles tendon can handle at any given stage, and these should then be progressed as the tendon grows stronger.
This YouTube Playlist of ours has lots of videos with advice on exercises for Achilles injuries.
Yes, tendons do have poorer blood supply than some other body parts, but that’s normal and it’s not due to injury. You can’t and shouldn’t do much to increase the blood supply to an injured tendon. Rather concentrate on giving your tendon the right mix of rest and exercise.
How we can help
Need more help with your Achilles injury? You’re welcome to consult one of the team at TMA online via video call for an assessment of your injury and a tailored treatment plan.
We're all UK Chartered Physiotherapists with Master’s Degrees related to Sports & Exercise Medicine. But at Treat My Achilles we don't just value qualifications; all of us also have a wealth of experience working with athletes across a broad variety of sports, ranging from recreationally active people to professional athletes. You can meet the team here.
About the Author
Tol, Johannes L., Filippo Spiezia, and Nicola Maffulli. "Neovascularization in Achilles tendinopathy: have we been chasing a red herring?." Knee Surgery, Sports Traumatology, Arthroscopy 20.10 (2012): 1891-1894.
Van Der Vlist, A. C., et al. (2021). "Which treatment is most effective for patients with Achilles tendinopathy? A living systematic review with network meta-analysis of 29 randomised controlled trials." British Journal of Sports Medicine 55(5): 249-256.