While I realize that the subject of DVTs (deep vein thrombosis) in endurance athletes is certainly not at the top of the list of health crises in the world, I do think that it’s important to talk about since it’s not something that many people are aware of. And hey, I’m a healthcare provider so I’m supposed to think and talk about these things!
Please note that while I am a nurse practitioner the information in this post is not intended to provide diagnosis (also, I don’t have my license yet…so I can’t technically diagnose you…). This is simply intended for informational purposes only. If you think you may have a DVT contact your medical provider or go to your nearest Emergency Department.
What is a DVT?
A DVT occurs when a blood clot (also called a thrombus) forms in the deep veins of your body, most commonly in your legs. They can cause pain or swelling, but also can occur without any symptoms.
People with certain medical conditions (clotting disorders, etc.) are more prone to DVTs as are people who are stationary for long periods of time, such as people who have undergone and are recovering from surgery.
A DVT is a serious medical condition because it is possible for the clot to break free from the vein and travel into your lungs (a pulmonary embolism).
DVTs affect about 2 million people every year and are failure to diagnose them causes up to 100,000 deaths per year. Also, about 85% of those who suffer from thrombosis during air travel are athletes (usually endurance athletes).
Who is at risk for a DVT?
There are three major risk factors for developing DVTs:
- Venous stasis: The veins in your body have valves to keep the blood from flowing backwards in them (veins carry unoxygenated blood back to your heart), when these valves are damaged, it becomes more difficult for the blood to travel against gravity and up to your heart causing it to sit in your veins for longer. Inactivity, damage to vessels, or surgery also can cause venous stasis. People who are on their feet for long periods of time also often have venous stasis, which is why so many nurses wear compression socks to work all day! The contractions of your muscles (especially in your legs) help move the blood in your veins towards your heart, so if you are not using your muscles then the blood does not move as quickly. What happens to blood when it isn’t moving? It clots.
- Hypercoagulability: This is essentially blood that likes to clot. Some people are prone to this on their own, but there are several factors that can make anyone’s blood hypercoagulable. Dehydration, pregnancy, oral contraceptive pills, as well as some other medical conditions can all contribute to this.
- Vessel damage: Surgery and trauma are the two greatest risk factors for damage to vessels, and vessel damage = increased clotting risk.
What are the symptoms of a DVT?
Symptoms of a DVT include:
- Pain/discomfort in one or both arms or legs
- Swelling, redness, and/or warmth in one or both arms or legs
- Decreased ability to tolerate standing or exercise
- Pain is often relieved by elevating the affected limb(s)
Why does this matter for endurance athletes?
Endurance athletes are exposed to many of the three major risk factors for DVT development on a daily basis. Repetitive micro trauma and increased vessel damage occur during long periods of intense exercise which increases the likelihood of getting a DVT. Dehydration contributes to hypercoagulability. These risk factors are then often combined with prolonged periods of immobility (traveling to or from a race, sleeping, recovering, etc.) which compounds the risk factors (especially venous stasis) putting athletes at an even higher risk.
There is also the issue of athletes having a lower resting heart rate than the general population (good for athletic performance, bad for blood clots). Lower resting heart rate means slower blood flow through the body. Is this starting to sound familiar? Slower blood flow means blood is more likely to clot. Add some dehydration on top of that and you’ve got yourself a recipe for a blood clot.
None of this is meant to scare anyone, I simply want to make sure that we are all aware of the risk factors and listen a little more closely to what our bodies are telling us. I often have pain or cramps in my calf muscles (they are horribly tight…I’m working on it), and every single time I worry about a blood clot. I have not had one, but it’s always in the back of my mind. If the pain in my calf lasted longer than an hour or two, it was swollen, or I had any shortness of breath (a symptom of a pulmonary embolism) you bet I’d be on the phone with my doctor immediately (who would probably tell me to go to the ER).
What can you do to prevent a DVT?
- Hydrate! (Also, coffee does not equal water and is not hydrating…)
- Move! If you are on a plane, get up and move every hour or so. If that is too difficult to do, make sure you do some exercises (ankle rolls, foot flexes, knee lifts, shoulder rolls, etc.)
- Wear compression socks. Yes, the good ones are expensive, but they are worth it (they are much cheaper than a trip to the Emergency Department). They help to keep the blood from pooling in your lower legs during periods of immobility, but are not a substitution for the first two things on this list.
If you have any symptoms that you think might be a DVT, please get in touch with your healthcare provider. Again, my goal is not to strike fear in the hearts of endurance athletes everywhere, it’s simply to give you the knowledge to know what goes on inside your body.