Bikes & Tech
Photo: Brad Kaminski

Technical FAQ: More on riding while on blood thinners

Lennard Zinn received myriad responses to a recent column about cyclists taking anticoagulant medication.

Have a question for Lennard? Please email us to be included in Technical FAQ.

Blood thinners and cycling

Dear readers,
I was amazed at all the mail I got about the post on cycling while on blood anticoagulant medication.

As I said in that post, I don’t think the risks are to be taken lightly, as the consequences of getting a bruise or a cut can be dire. And as I found out when it happened to me, it is not that unlikely for a fit cyclist to find him or herself being prescribed an anticoagulant for a short term due to PE (pulmonary embolisms), DVT (deep vein thrombosis), or ischemic stroke, or for the long term due to AFib (atrial fibrillation).

Cyclists of any age can get pulmonary embolisms. One of the risks of transcontinental flying can be PE (that’s why the airlines have videos instructing passengers to keep moving as well as suggest wearing compression socks or tights). Athletes tend to have lower blood pressure and heart rate and may also be dehydrated while flying or driving long distances following hard racing or training (or have had recent surgery, as I had). These things can lead to the pooling-up of blood in the legs or feet with the possible complication of clots forming and then being pushed up into the lungs.

1999 Liège-Bastogne-Liège champion Frank Vandenbroucke died of PE in 2009 after concluding his racing season. The ones who don’t die generally get put on blood thinners (anticoagulants), as I did. Chris Horner had PE in 2011 and went on anticoagulant meds, two years before winning the Vuelta a España.

So, if you or someone you know happens to be on anticoagulant medication and wants to ride, particularly mountain biking or cyclocross in which the likelihood of falling off and getting bruised is high, you might want to keep reading below. The first letter puts a human face on what can happen if you get a bruise while on blood thinners. He sent photos to me, but I deemed them too gruesome to include here.
― Lennard

Dear Lennard,
In April 2002, I had a cryptogenic ischemic stroke. I was 35 and the best shape of my life. Since no cause was found, I was put on blood thinners as a precaution. So, I’d like to share information about my unfortunate accident a year later while on blood thinners.

I was stationed in Germany and riding my MTB on bike/pedestrian paths headed to my favorite trailhead, six miles one way from home. About a mile from the trailhead, I jumped off the path and onto the street to avoid a group of elderly people. When I attempted to jump back onto the path, my rear wheel caught the curb and I slid. Then I jumped over the bars as I was going down and landed squarely on the left butt cheek.

It was extremely painful, so I waited a few minutes and then thought, “it was just a hard fall; I’m tough and will keep riding.” At the trailhead, I started feeling the back of my left thigh getting tight and started feeling light-headed, so I headed back home. The pain became almost unbearable, and I could not sit on the saddle. I got to the ER and was admitted after an ultrasound showed a very large gluteal hematoma. I spent 45 days in the hospital and needed three surgeries over a six-week period. On top of that, the wound became infected, and it was during that horrible heatwave in Europe in the summer of 2003. There is no air conditioning in Germany. I was on the 11th floor.

This is what can happen when you have a hard fall while on blood thinners. Thanks for hearing my long-winded story. Please stay safe and vertical while out riding.
— Kenneth

Dear Lennard,
Contrary to your statement that there are no antidotes for Xarelto and Eliquis, there is an antidote now available for both.

It might be worthwhile to put out a correction.
— Robert

Dear Robert,
Thanks; I had not kept up to date on that. When I had my PE a couple of years ago, there was no antidote for Eliquis or Xarelto. Andexxa was approved less than a year ago (May of 2018).
― Lennard

Dear Lennard,
I wanted to let you know that in addition to Warfarin, Pradaxa (Dabigatran) another blood thinner is used for treatment of pulmonary emboli, atrial fibrillation, and DVT and is reversible. It has its own dedicated and very effective reversal agent (Praxbind), which is widely available. I am a cardiologist in upstate New York, and about 10 of my patients have needed immediate reversal due to trauma, bleeding, or the need for immediate surgery. My surgical colleagues have told me there was zero bleeding once the reversal agent was given. I would not want anyone to be cavalier and take Warfarin or Pradaxa or any other anticoagulant and go out and take unnecessary risks. If you have, for example, a head trauma on Warfarin or Pradaxa, reversing the effect of these drugs does not stop the damage that has already occurred from the bleeding. However, a reversible anticoagulant will make it much easier for a surgeon to do any corrective surgical actions necessary to stop or control the bleeding. Not a situation anyone wants to be in.

I wanted to let you know this. As for my more active patients who are on blood thinners, I try to get them on Pradaxa due to the reversal agent, but sometimes insurance won’t cover it. Xarelto and Eliquis have a reversal agent, but it is not as widely available as the reversal agent for Pradaxa and is harder to administer.

Basically, any trauma, especially head trauma, while on any of these meds is a nightmare for both patient and doctor. I would recommend anyone who goes out and rides on an anticoagulant have a medical alert bracelet and have on their phones the meds they take to alert first responders and that their riding partners have full knowledge of them being on an anticoagulant.
— Dr. James Connelly

Dear Lennard,
In Lennard’s reply to Christian’s question about blood thinners, you wrote, “But there is no such antidote for Eliquis or Xarelto, which have largely displaced Coumadin by being easier to take, not requiring frequent testing of clotting factors.”

Good news! The FDA has approved an antidote that works with Eliquis and Xarelto. Its name is Andexxa and it was developed by a company named Portola Pharmaceuticals.
— William

Dear Lennard,
Good info in your recent Q&A on blood thinners. I have been on Warfarin/Coumadin since a DVT/PE in 2009 and will be for life (I was diagnosed with Factor V Leiden, a clotting disorder). As you note, Vitamin K can help reverse the effects of Warfarin; hence, it is my thinner of choice while leading an active lifestyle. I no longer do road races (crits on thinners just don’t seem like a good idea!) but still do group rides and have replaced road racing with triathlons.

However, there is now a reversal agent for Eliquis & Xarelto. It is the first reversal agent for “next-gen” blood thinners, so they are now, therefore, viable choices for people with active lifestyles.

Unfortunately, my insurance does not cover “next-gen” thinners, so I am stuck with Warfarin. Other than a few dietary and behavior modifications, it does not impact me at all. Athletes on blood thinners just need to make smart, informed decisions and weigh the risks. But you absolutely can still enjoy the activities you always have.
— Mark

Dear Lennard,
Regarding Christian’s question about cycling while on anticoagulants, I have seven years of experience in that department. I’m on Warfarin for life due to two episodes of DVT (blood clots in calves) at ages 40 and 42, the second of which resulted in bilateral PE (pulmonary emboli) with a saddle embolus. Thankfully, I recognized the symptoms and the hospital put me on Heparin quickly, so I’m still kicking.

Naturally, the question of lifestyle changes came up when I was put on long-term anticoagulants. For me, giving up cycling was a non-starter. Having just gotten back into road racing after a 10-year hiatus, I wanted to continue racing as well. I talked it over with my hematologist, and in the end, he shrugged and said, “Well, you can’t just stop living.” Yes, there are risks, most notably a bad brain bleed should I crash and hit my head, but here’s how I manage them:

1. I take Warfarin as my anticoagulant. It’s been around for over 60 years and is well understood, readily available, not likely to be recalled by the FDA, and readily reversible in case of an emergency. I self-perform monthly blood tests to ensure I’m taking the correct dose, and I manage to stay very close to the low end of my “therapeutic range.” None of the arguments I’ve heard for the next-generation anticoagulants have made me consider switching. Warfarin works for me.

2. I typically ride with others, and I tell my riding partners about my situation. On any given day, it’s likely I’m riding with someone who knows I’m taking anticoagulants and might need urgent help if I wreck.

3. I wear a RoadID that includes the line “I AM ON WARFARIN,” and the lock screen on my phone says it too.

4. I manage my risks on the bike. That’s not to say I don’t take risks; I commute in heavy traffic and I still race (I’ve upgraded to Cat. 3 on the road since starting anticoagulants, and I love criteriums). But I’m not a daredevil descender, and I’m not one to duke it out in a big pack sprint. If I’m getting a funny vibe, I’ll sit up and enjoy the scenery.

I realize that mine is a purely roadie perspective, and that off-roaders face the prospect of a bad crash in a remote area with limited access. I’m not likely to take up serious mountain biking now, but I’ve also been told I’m crazy for riding in traffic and for road racing. Everybody’s risk equation is different.
— Garrick

Dear Lennard,
I’m one of the unlucky with a genetic predisposition to clots, Leiden Factor V, so I’m on blood thinners as well. My first clot was 25 years ago, but I was too dumb to take serious the symptoms and lucky enough that it dissolved on its own and didn’t kill me in the process.

The next one came six or seven years ago, and that time I knew something was amiss. My primary care doc is also one of my cycling buddies, and he grounded me from riding for a few weeks and put me on Lovenox to dissolve the clot.

I’ve been on Warfarin ever since, rather than the newer drugs. No. 1, I’m cheap. No. 2, it’s reversible with a shot of vitamin K. No. 3, and with my doc’s OK, I keep my INR (coagulation factor) right at or slightly below the generally accepted level (I aim for 1.8 to 1.9) to lower the risk of excessive bleeding or internal hemorrhaging but still high enough to deter clots. He doesn’t want me racing crits or going gonzo on the mountain bike, but he tolerates me racing ’cross and an occasional road race. At my age of 63, I’m not that interested in wrecking regardless of blood thinners, so I’m generally not pushing the limits of tire adhesion on steep downhill decreasing radius turns. I also wear only Bell or Giro MIPS helmets.
— Dale

Dear Lennard,
I second your advice against laying off mountain biking while on a short-term course of anti-coagulants. Actually, I’d go so far as to say no riding except on the trainer. I had a similar experience six years ago post-op to repair a collarbone that I broke in a crash. Doc originally said he wanted a six-month course of Coumadin/Warfarin. I did my own research that suggested three months was fine and got a second opinion to support it.

I have known people who continued to ride on anti-coagulants, some on a three- to six-month course, others on it for life. If you are on it for life and unwilling to give up the sport (I can understand why), I’d suggest being careful how and where you ride and who you ride with. Understand that you’re assuming more risk, but of course life, even without cycling, is never 100 percent safe anyway.

For a short course, definitely take a break from the sport completely (again, trainer is OK). Try running, swimming, hiking, or hit the weight room harder. Continuing to ride is just not worth the risk.
— John

This one is from a friend of mine who has been a super-strong bike racer for many decades:

Dear Lennard,
I just read your column on riding and anticoagulants. A week or so ago, I was diagnosed with a pulmonary embolism following a DVT in my leg. Since this is not my first time, I’m now staring at having to go on an anticoagulant for the rest of my life. After reading your column, I was wondering if you have any advice on which one to use and, specifically, which one will have the least effect on my athletic performance. I’ve been on Xarelto for about a week and I already suspect it is causing me to gain weight. I’ve been on Warfarin in the past with no ill effects, but don’t know if there are things to worry about long-term.
— Bill

(Since I noticed no ill effects with either Eliquis or Xarelto, I didn’t have any advice for him. –LZ)

Dear Lennard,
I’m on blood thinners also. My cardiologist was more concerned about road riding than mountain biking. I agree with that, as I can control the risks; I take off-road by my caution level. But on the road, some of it is out of my control and depends on the cars passing me. I still ride both. I have the rear-view radar light that communicates with my Garmin to at least warn me about approaching cars, so I can do threat analysis by knowing when to check my rear-view mirror. If they appear to be too far right or swerving, I get out of the way to the extent I can.

And, there is a new reversal drug for Xarelto available. It costs a bunch, though, but it might be worth carrying a dose along because not all first responders have it.

Instead of epic challenge rides, I now do RAGBRAI. Loads of fun.
— Bill

Dear Lennard,
If I were the patient Christian, I would refrain not only from MTB but also road riding. I would restrict my riding to trainers.

The situation is temporary. The consequences of a dislodged clot could be very serious and permanent. Prioritize long-term recovery and goals!

My pelvis was shattered when I was hit by a truck from behind while I was riding on the road. I also had a major vascular injury. During the first surgery, estimated blood loss was 5 L — essentially all of my blood. I was unable to ride (or even bear weight on one leg) for three months. I’m lucky to have survived. Things might not have gone so well had I been on an anticoagulant.
— Ray