Runners and Blood Clots: What You Need to Know

January 17, 2013

I just heard that you developed two blood clots in three months! How is it possible for a person like you, who is fit and healthy, to develop clots? —My family and friends.

"Listen to your body."

I’ve heard it a thousand times and have written it just as many. Little did I know those four words would save my life.

I was flying home from Munich last fall. I was in Europe for a site visit for our upcoming Danube River Marathon Adventure and had quite the expedition to arrive home. It included a two-hour cab ride and a two-hour flight, followed by a 10-hour flight to ORD. Needless to say, it was a lot of sitting and a lot of time in the air—but not something that was new for me.

About halfway through the flight, my calf started aching like it was going to go full throttle into one of those nasty charley horses. It never seized, but it continued to ache. A little voice whispered, “It is a blood clot,” but I thought to myself, “Not me! I’m an athlete who’s healthy and fit. I just finished running Rim to Rim and the Inca Trail Marathon!”

Fast forward one week later. I am still walking around with a dull ache in my calf, and I know in my gut and my head it just may be a blood clot. It didn’t feel like an injury because it didn’t respond to rest, flexibility, or ice. It remained a dull ache that felt like it would seize at any moment.

I connected with my doc and she immediately sent me to get a Doppler ultrasound to rule out a clot. After 60 minutes of ultrasound searching, the technician found a small but deep blood clot. Thank goodness she had tenacity, as the first technician was ready to call it day after about five minutes.

I was put on a round of aspirin, sentenced to wearing really ugly compression hose for two weeks, and allowed to run at easy efforts for a month.

I went on living my life, traveling, taking my aspirin like a good patient, moving more, and sitting less. Until late-December, when after flying home on a four-hour flight from California, the calf pain returned. This time, it was more intense and a little higher in my calf. My gut told me it was another clot, and this time I reached out to my doc sooner and listened more quickly.

After a trip to the ER, it was official. I had a second clot, and this time it was larger and more significant. The risk is that the clot would travel to my lung (pulmonary embolism), a condition that can quickly turn fatal. I have a friend who raced an Ironman this fall and had the very same symptoms, and by the time he got the diagnosis, he had developed two clots—one in either lung. Fortunately, he’s doing well and recovering.

So, I went on three rounds of injectable blood thinners and pill-form thinners to prevent further clotting and reduce the coagulation factor in my blood.

I’ll spare you all the drama (more ugly hose, fear, and a few tears), but I’m sharing this with you because I never thought it could happen to me, an athlete. I moved all the time, ate well, and was in good health.

How could I develop two blood clots in such a short period of time?

Good question! I’ve been analyzing the heck out of this for weeks, and there are several circumstances that increase the risk factors for athletes developing blood clots. What confused me the most was I travel for a living. I’ve been all over the world—so why now? Please keep in mind, this relates to my health and it may not be true for you. The intent is not to scare, but to inform.

• Inactivity. I sat for a prolonged period of time. Immobility is on the top of the list for risky behaviors for clotting. In total I sat for over 14 hours with very little movement on my way home. I usually get up on flights every one to two hours and walk around, but I fell asleep for hours this time and didn’t move as much. I also forgot to wear my compression socks as I normally would.
• Dehydration. It decreases the plasma in our blood and increases the viscosity, making it thicker. I confess I enjoyed the free wine aboard the riverboat and was likely quite dehydrated on my journey home. In general, most endurance athletes likely walk around in a mildly dehydrated state due to training and racing.
• Fitness. With fitness, our body increases the red blood count and oxygen-carrying capacity, which can increase the thickness of the blood.
• Medications. I was in a state of hyperthyroidism due to over-medication. Short story is I made some serious diet changes upon finding out I wasn’t hypothyroid (gluten-free/Paleo-ish), and in that time I went from being hypo- to hyperthyroid.  That can increase the coagulation factor in the blood.
• Genes. Finally, it could be that I carry a genetic trait that lends itself to the development of blood clots. That doesn’t seem likely, as at 45 years old this is the first time this has happened. My money is on the Perfect Storm theory, as I had a host of variables that all came together at the same time to create the first clot. At that point, I was at risk for developing another in the same leg. But I’m not House. I’m not a doctor and I don’t play one on TV. I’ll let the doctors continue to search for the whys.

The key is to be aware as you train, travel, and race. Airhealth.org says that about 85% of air travel thrombosis victims are athletic, endurance athletes like marathoners. They also cite the following athlete risk factors for air travel:

• Low heart rates and blood pressures
• Bruises or fatigued, sore muscles (i.e. post race)
• 82% are under the age of 60
• Altitude can increase coagulation factors

Be Aware of the Signs and Symptoms During or a Few Days After Flight (or Long Drive)

• Often feels like a muscle cramp that doesn’t let up in time
• Can feel worse when standing or walking
• Swelling in one leg (versus both as is normal in flight or driving)
• Bruise or tenderness in lower leg or behind the knee
• The area is warm to the touch (this wasn’t the case for me)

More serious Signs and Symptoms

• Unexplained, sudden shortness of breath
• Rapid breathing
• Cramp in your side or chest, painful breathing (my friend said it felt like back pain)
• Chest pain radiating to the shoulder
• Fever
• Coughing up blood
• Feeling lightheaded and dizzy or fainting

I was lucky because I knew in my gut it was likely a clot, but had I been coming home from a race like my friend, I might have blown it off for a calf strain. In some cases, your doctor may miss it as well. Be informed, listen to your body, and know the signs and symptoms. If these symptoms line up with your condition, insist on an ultrasound.

Prevention Strategies

How can we can help prevent blood clots on planes, trains, and automobiles?

• Perform leg extensions every 15 minutes while seated.
• Get up and out and move around every one to two hours.
• Hydrate with an electrolytic beverage (tomato juice, sports drink) versus water and avoid alcohol – read why here
• Be aware of your medications and the risks, and you and your family’s health history
• Graduated compression socks can reduce edema and risks of developing clots. Talk to your doctor before wearing as they are not recommended for people with circulation problems caused by arterial insufficiency.

To learn more about DVT (deep vein thrombosis) visithttp://www.preventdvt.org/.

I’m going to write it again because it is so important – listen to your body, know your body, and be mindful as you travel through life. It something doesn’t feel right, get it checked out.

Happy Trails.

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