Iliac artery endofibrosis #1 – symptoms

It's obvious once you know

In my latest post, I mentioned that I would be start a mini-series about my experience with iliac artery endofibrosis. Since I have plenty of time on my hands at the moment, I’d like to share what I’ve learned about dealing with this condition. Although awareness of this injury is growing, athletes still waste valuable time before receiving an accurate diagnosis. Or worse, they never get diagnosed at all, potentially putting their entire careers at risk or losing their joy in cycling. I guess a good starting point for this series is where every injury story starts: with the symptoms.

Pick up the vague stuff early

The symptoms pinpoint why an early diagnosis is so challenging. They tend to be vague and inconsistent. The classic symptom of one leg giving out when riding above your FTP might not be that apparent, especially in the early stages. Looking back, I think first signs appeared about six months ago, long before I ever considered artery problems. You could see these as early warning signs, although they might not mean anything on their own. Then there are red flags that should raise concern, along with obvious indicators that become easy to recognize once you know what to look for. Finally, there’s the weird stuff I experienced, which may or may not be related. Let’s break them down.

Early warning 🧐

• Unexplained inconsistency – alright this might not be an actual symptom, but it’s still important. Coming into key sessions or race days well-rested yet underperforming can be a sign. Of course, everyone has off days where the legs just don’t show up, but if it happens repeatedly, it’s worth taking a closer look at what’s going on. Keep in mind that if you’re unaware of a unilateral problem, you might not even realize that one leg is actually responsible for the issue.

• Only one bullet – in races, my single-effort power was still solid, but I struggled with repeated efforts. This was probably because one leg wasn’t able to recover as it should, leading to an overall decline in performance. Remember when I wrote about my ‘mentally failing’ in races. I have second thoughts on this one now.

Red flag 🚩

• Unsymmetrical post-ride recovery – this stood out to me even more than the differences I noticed while riding. After hard or long sessions, I consistently felt more muscle soreness and heaviness in my left leg compared to my right.

• Tingling sensations – during long rides, I experienced tingling, particularly in my lower leg and shin.

Obvious 🆘

• Constant urge to stand up – I became much more aware of this behavior after doing my blood pressure tests. During longer tempo efforts, I felt a constant need to stand, even though I normally prefer to ride seated most of the time.

• Aero is the enemy – riding in a tucked position or in the drops while pushing above zone 2 became nearly impossible. My left leg would start to “blow up”, making 280 watts feel more like 400.

Weird Stuff 🤔

• One foot is colder – during winter rides, my left foot often felt slightly colder than my right. There can be many reasons for this, since no one is anatomically perfect, but I suspect it might be related.

• Office chair tingling – if I sat in my office chair for longer periods, especially after a training ride, I would feel tingling in my left foot. It is similar to the numb, pins-and-needles sensation you get after sitting on your hand for too long.

• Stretching numbness – certain stretching positions would trigger numbness and tingling. For example, child’s pose would make my left leg feel numb.

You’re not crazy, but don’t drive yourself crazy either

You will almost always feel something somewhere in your body. When you become hyper-focused on every sensation, whether on or off the bike, it’s easy to convince yourself you have an injury. The key is to identify true asymmetries and abnormalities. Try to recall how things felt a year ago – endofibrosis develops gradually, so sensations that feel “normal” now may actually be abnormal. Its symptoms are often vague and can fluctuate from day to day, creating the perfect recipe for driving yourself crazy.

I’ll cover the diagnosis in the next article of this mini-series, including a more detailed explanation of the blood pressure tests I performed myself and the assessments carried out at the hospital. Thanks for reading!