Blood Clots and the Endurance Athlete

Blood Clots and the Endurance Athlete

The Diagnosis

I am Steve Lehman, a 58-year-old, endurance athlete and I developed blood clots.  As a World and National Champion and World Hour Record holding bicycle racer, I believed I was “bomb-proof”.  I’m not. In fact, I’m lucky to be alive. The same blood and vascular system that have helped me achieve these lofty goals are also prone to producing a deadly, silent killer, the blood clot.

On August 25, 2005, I won the 2000 meter Pursuit in my age category at the US National Track Championships in Indianapolis, Indiana.   The next day I woke early, packed my car and began the nine-hour drive home.  I stopped two times en route to fill one tank and empty the other.   The first night home I cramped in the right calf while sleeping.  My poor wife, Sandy, was startled awake and immediately rubbed the cramp out.  That was pretty much it.  For the next several days I suffered from the effects of my effort at Nationals. Both calves were extremely tight and sore and I had a rather severe case of “Pursuiter Cough.” Pursuiter Cough is a malady common among pursuiters. When competing in dry air while breathing heavily through the mouth there is a burning or abrasion of the lower throat and bronchial passages.  It can be mistaken for asthma, although the subsequent cough and shortness of breath are usually gone within several days and there are no lingering effects.

Late August is usually the end of the season, but I still had an obligation to members of my track training group.  Several riders were in their final preparation for the World Track Championships in mid-September and I still had to remain fit for the Bermuda Grand Prix Stage Race beginning on September 23.  So, during the next two weeks I continued to do two to three hour road rides to stay fit and early morning track sessions, in part, to help maintain speed. The calf tightness subsided, but there remained a dull ache just behind and below the left knee.  My cough also disappeared, but I still became short of breath at efforts that wouldn’t normally cause me distress.  I would implore my road riding mates to keep the pace down and I couldn’t even finish a proper track warm-up.  Again, I was writing this off as lingering effects of the race in Indianapolis, although deep down I knew something was dreadfully wrong.  Little did I know each time I even got out of a chair I was playing Russian Roulette. I was throwing clots.

Having had a history of blood clots following a bike/auto related trauma in 1996, I started to wonder.

Having had a history of blood clots following a bike/auto related trauma in 1996, I started to wonder. I went to my computer and did a search by simply typing in “cyclist with calf pain.” From that search I went to and that started the ball rolling.  Here I learned some elementary information about signs and symptoms of DVT’s(deep vein thrombosis).  Through further investigation I stumbled upon a most frightening web site .   At this site I found account after account of athletes'(or their surviving family member’s) experiences with DVT’s and pulmonary embolisms(PE’s), clots in the lungs, which are often discovered postmortem.   Now they really had my attention.

I called my best friend, who happens to be a doctor (a general internist), and told him of my suspicions and desire to have a test of my calf.  He agreed and ordered a Doppler Ultrasound.  Despite no real symptoms other than an ache, I had a clot in a most common location, the popliteal vein at the top of the calf. To prevent any further movement of the clot, I was instructed to remain at the lab until a wheelchair would arrive. I was then taken directly to express admissions at the adjoining hospital.  Not having to go through the long wait at the emergency department indicated the seriousness of my condition. While in the express admissions unit several vials of blood were drawn to check for any genetic predisposition to clotting. Unfortunately, I would find out later, the collected blood clotted on the way to the lab. Before I had a bed, I was whisked away to radiology for a CAT scan of my lungs.   Bingo, my worst suspicions were realized, I had bilateral pulmonary embolisms (PE’s).

The next three days at the hospital I was ordered to stay in bed. I was put on an intravenous drip of heparin, a fast acting blood thinner, and warfarin (more commonly known as Coumadin), a long term blood thinner that is to be taken for a period of three to six months.  While on warfarin, the blood is maintained in an anticoagulant state. Which means your blood is kept in a condition where it flows freer and therefore does not clot as readily. Contact sports such as falling off your bike are not recommended, as the serious effects or chance of death from even a slight head trauma, and the resulting pressure on the brain, are considerably greater.  Basically, this means no road riding for several months. So, I guess I’ll be seeing you next year. This brings me, however, to the real reason for this lengthy report.  I want to make you aware of this danger that faces any of us that have conditioned our bodies for endurance athletics. Basically, this means if your butt hits the saddle on a regular basis or you have more than one pair of running shoes (that you actually use), this report applies to you.

Who’s at risk?   Why?  What can you do to limit the risk of blood clots?

Of the studies I came across concerning so called “economy class syndrome” it was reported that 1% to 10% of air travelers on flights from two to ten hours in length developed blood clots.   This is a very wide range.  However, the most comprehensive and generally accepted study, LONFLIT by Gianni Belcaro, determined that 4.5% of long distance air travelers developed blood clots.   Also noted was the fact that there was no real difference in the frequency of clotting cases in economy, business or first class.  The’s two year registry determined “about 85% of air travel blood clot (thrombosis) victims are athletic, usually endurance-type athletes . . . ”  Obviously, no risk factor even came close to that of the athlete. Another important point revealed by this study was that the victims in this group were younger than you may expect, 82% of them were under 60.   Hey, that’s you!

Why are we at risk?

Well, through our conditioning we have developed bodies that are a bit different from the average person.  We are unique and need to be aware of that.  Modern medicine deals mainly with sick people, not otherwise healthy, physically fit individuals.You must understand that you are your best advocate.   There are the obvious differences like larger quadriceps, leaner physiques and better tan lines, but what about our blood. Cycling, or any endurance sport, generally develops the muscle that pumps blood, the heart. To that end we typically wind up, and relish, our lower heart rates.  My resting rate is usually pegged at 40 beats per minute. Our training also “improves” our hematocrit or red blood cell count by keeping it’s oxygen carrying capabilities at our genetic maximum. This maximum performance of our blood also increases its viscosity or resistance to flow. My hematocrit level is at 46% or about just a bit above normal for an adult male.   However, dehydration has a tremendous effect on the reduction of plasma in our blood which increases the viscosity (thickness) dramatically. It should go without saying, we are typically in some state of dehydration. Make a note of that.

So, what can we do to help prevent blood clots on long flights, bus trips or in an automobile.

Frequent leg flexing is one of the simplest and best preventive measures.  Effective seated exercises can be found at  Along with frequent (every 15 minutes) flexing, you should get up and walk at least three times on a trans-Atlantic flight.  If driving, stop the car and walk every two hours.   While the benefit of compression stockings is sometimes disputed, I will be wearing a pair on future trips.  They have stronger compression at the ankles and gradually less and less compression as they move up the leg.   This design actually forces the blood flow up the leg, thus increasing velocity in the most at risk area of the body. Understand support stockings are not the same and should be avoided.  Remember the advertisement for Camelback(a backpack drinking system), “Hydrate or die?”  Well, this expression has relevance in this case. Drink an eight-ounce serving of an electrolyte-laced beverage, like Gatorade, every hour. Studies have shown that water alone provides no benefit.It only causes you to urinate more and increase the viscosity (thickness) of the blood. Three 20 oz. sports drinks will handle an eight-hour flight. Finally there is pharmaceutical prophylaxis for those of you who are, like me, at serious risk or must sleep during a long flight or drive.   As an athlete involved in a “contact sport” you should talk to your doctor about the use of a quick acting and quick clearing drug such as Lovenox.  While Aspirin is effective in the prevention of many disorders to include the prevention of arterial clots, it does not work on venous clots.

Symptoms and Self-Advocacy

Here is the list of symptoms as found on the website:

  • Leg symptoms (DVT) may appear during flight or in the next few days:
  • Sudden swelling in one lower leg. (A little swelling in both legs is normal in flight)
  • Cramp or tenderness in one lower leg
  • Bruise or swelling behind knee

Chest symptoms (PE) usually appear 2-4 days or more after the initial blood clot, which you may or may not notice:

  • Shortness of breath
  • Rapid breathing, panting cramp in your side, painful breathing
  • Chest pain, sometimes accompanied by shoulder pain
  • coughing up blood
  • fainting (often the first sign, especially in older people)

Tell the doctor that you have flown [or driven a great distance] recently and that you suspect a blood clot.


DVT is usually mistaken for a cramp, even when the victim is a physician. Those who seek treatment are usually misdiagnosed at first, increasing the risk of permanent vein damage and increasing the risk of death.  Here are two simple ways to avoid misdiagnosis.

  1. If you have leg symptoms and the doctor says you have only a muscle sprain (or anything else other than a DVT), insist on an ultrasound scan of the leg. We [] haven’t heard of any case where an ultrasound scan failed to identify a symptomatic leg clot.
  2. If you have chest symptoms and you are being told you have a chest infection, anxiety attack, heart attack, or anything else other than PE (pulmonary embolism), ask for a blood oxygen measurement.  A small clip (no needle) placed on your fingertip measures blood oxygen.  If the reading is below 80, you need a lung scan to check for PE (unless there is some reason for low blood oxygen, such as emphysema). Since you won’t remember this when the time comes go to for a free leaflet to carry with your travel documents.

Understand, you know your body.  You know when something is wrong.  Two weeks after I did an explosive event like the Pursuit and won the National Championship, my calf muscle hurt.  Of course it would!  Okay, if that wasn’t enough evidence of clots, I became short of breath when I was doing 30 miles per hour on my bicycle.  Poor Baby! Who wouldn’t?  There was no swelling or bruising of my calf, just a dull ache.   With “normal” activity I had none of the chest symptoms, but I knew something was wrong.  That first evening in the hospital my vital signs were – temperature at 97 degrees; heart rate, 42 beats per minute; blood pressure, 106/60; respiration normal and oxygen level high at 98%.   Except for the clots coursing through my body, I was asymptomatic, but I knew something was wrong.  I advocated for myself, requested the test, and am alive to tell you about it.

Remember we are different. Viva la Difference!


Photo by Markus Spiske on Unsplash

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