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Arm Pump

by Dr. Dale McDonald BA, DC, CSCS, CCSS(C) Resident

Racing Psychologist, Dr. Patrick Cohn has an audio CD that explains the link between the mind and arm pump.
Arm Pump - The Silent Killer
If there are two words that strike fear into the hearts of motocross racers, its "arm pump" – that mysterious ailment that comes on near the end of your moto, makes your arms feel like concrete blocks and your hands go numb and fly off the grips. Arm pump has been responsible for countless crashes over the years. As a former racer, I remember getting arm pump so badly I couldn’t pull the clutch lever, couldn’t pull the brake lever, couldn’t hold onto the grips and, worst of all couldn’t shut the throttle off! Arm pump ranges in severity from slightly annoying to completely debilitating. One would think that an ailment that affects almost every rider at some point in their career would be thoroughly researched by the motocross and medical communities and a solution common knowledge. Unfortunately, that has not happened and folklore at the racetrack runs rampant as to how to prevent getting rock hard forearms. This article will attempt to boil arm pump down to the simple basics, separate fact from fiction, extinguish the folklore and offer some basic, factually driven solutions.

Layman’s Description
Arm pump is academically known as chronic exertional compartment syndrome (CECS). At its most basic; arm pump is the failure of blood to leave your forearm fast enough. New blood is constantly coming into your forearm, and if the old blood is not removed, backpressure builds up. The forearm compartment is not elastic, so when the pressure does build up, other structures such as nerves and muscles get compressed and lose their ability to function properly. Picture stepping on a garden hose; this compression of important structures is what causes the loss of sensation and inability to contract your muscles. It is important to remember that not all forearm pain is caused by arm pump; you may think that your pain is a result of arm pump when in fact it may be from something else entirely. Many other factors can cause forearm pain including carpel tunnel syndrome, epicondylitis (golfer’s or tennis elbow), arthritis, shoulder and neck problems, fractures and previous injuries. If you suspect any of these other ailments, see you Doctor for a full medical evaluation. In the interest of this article we will deal with forearm pain from arm pump only.

Technical Description
To fully understand arm pump, let’s first take a short lesson in muscle anatomy. Muscles are often found together it what are called "fascial compartments". Fascial compartments contain muscle wrapped in a layer of fascia. Fascia is the stuff that gives muscles their form much like the casing that wraps a sausage. Although fascia is very strong, it is not elastic. Since the fascia compartment is so inelastic, any increase in volume will cause pressure increases within the compartment. During intense exercise, muscles require large amounts of oxygen rich blood to keep the muscle performing at peak levels. This increased volume engorges the muscle within the inelastic fascia resulting in increased pressure within the compartment. Since we all remember that fluids are incompressible, and blood is most certainly a fluid, the increased pressure buildup within the fascia makes the muscle feel hard as a rock. When the compartment pressure builds up high enough, blood vessels can collapse which restricts or stops the flow through the vessel. Veins typically have a lower internal pressure and have thinner walls than arteries. Because of this, veins will collapse from external pressure long before arteries. When this happens, venous flow reduces while arterial blood continues to enter the fascial compartment but is restricted from leaving. This restricted outflow increases the compartment pressure and is what causes the muscle to feel hard. If the compartment pressure rises high enough, even the capillaries and arterial vessels can collapse, resulting in a painful condition of oxygen deprivation. Acute compartment syndrome is the rare worst-case scenario of a compartment syndrome. A medical emergency, acute compartment syndrome is often the result of trauma (i.e. a hard crash). Acute compartment syndrome can afflict any muscle in your body, and should be suspected if the area becomes increasingly more painful, swollen, red and hot in the few hours after an injury.

Training legend, Gary Semics has a video on arm pump detailing what he believes is the most effective way of eliminating arm pump.

Why the Inequality in Blood Flow?
The previous paragraph outlines the discrepancy between blood coming into your forearms versus blood leaving your forearms. Why the difference? The amount of used blood that you can effectively remove from a muscle is called your "venous return" and is a measure of your cardiovascular fitness. The more cardiovascularly fit you are, the better job your body does at removing used blood from muscle and returning it to the lungs (where it gets loaded up with fresh oxygen). If your cardiovascular fitness is not as good as your muscular strength (i.e. holding on to the handlebars with a death grip for two 30 minute motos), you will have problems.

Surgical Approach to a Solution
Pro riders have sometimes taken drastic measures to reduce the pressure that causes arm pump. Fasciotomy is a surgery that releases the compartment that houses the muscle, blood vessels and nerves. Little research exists regarding the effectiveness of surgical fascial release for chronic exertional compartment syndrome; however conservative estimates place its effectiveness at just over 50%, meaning that nearly every other rider who gets this procedure done has no noticeable improvement. (Note that surgery is very successful and in fact necessary for acute compartment syndromes). Further complicating the recovery is the formation of scar tissue over the area that was just released. Scar tissue can actually make the symptoms of arm pump worse than before the surgery. Several top pro riders can vouch for this.

In the U.S., we have become accustomed to modern medicine providing the passive, easy fix. Popular culture is full of solutions to just about any ailment you have just by taking a pill. Bladder problems? Take a pill; Memory loss? Take a different pill; high cholesterol? Take three pills! In a day in age when we all want a drive through solution to what ails us, it’s no wonder that so many are seeking a solution to arm pump through surgery. If you take the time to read and understand the mechanism that causes arm pump, you can most likely eliminate this beast from your life and save your self the time and pain that comes with surgery. Unfortunately, there is no simple, one sentence solution.

The Obvious Solution
The first and most important thing you can do to eliminate arm pump is to ride, ride, ride. There is no better sport specific exercise for MX than riding. If you are a normal weekend warrior and don’t always get to ride, then the most important thing you can do is to improve your cardiovascular fitness through supplemental training. (See the Racer X archives section on training for several complete workouts). Doing substantial amounts of endurance training will promote the growth of more small veins in the body (a process called neovascularization). More veins equal more pathways for used blood to leave a muscle (your forearms in this case).

Please take note that the types of exercises that are most beneficial are total body exercises, NOT isolation exercises like arm curls or squeezing a tennis ball. You must use total body exercises to condition your body to become efficient at delivering oxygen rich blood to muscles and to remove byproducts (like lactic acid) more efficiently. This can only be done with total body, cardiovascular exercises. Running is a personal favorite of Dr. Macdonald’s, as it gives a great cardiovascular challenge and can be tailored to mimic race day (for example – try running 2 sets of 35 minutes at a "tempo" pace (75 – 80% of your maximum heart rate), with the same length of rest as you get between motos. (Use this calculator to determine your heart rate training zones. There are many ways to determine your max heart rate, so if you want to take a more scientific approach check out this website.) You can also calculate your heart rate training zones based on a Lactate Threshold test. Check out this article for details. So remember, to increase your chances of eliminating arm pump, you must improve your total body cardiovascular fitness.

Race Day Solutions

There are also some things that can be done while you are at the track. A very thorough warm up prior to your race will help kick start your circulation. In fact, going for a moderate run (20-minutes) will warm you up to the point where you begin to sweat. This amount of warm up will ensure that your venous return is working well; allowing you to get rid of used blood more efficiently. Don’t worry about being a little tired from your warm up – you can finish your warm up 30-minutes before your first moto and still reap the benefits. Most riders suffer from arm pump worse in the first moto than the second – this is primarily because their venous return is not up and running before they get on the track: When it comes to arm pump, it is better to be a little tired than a little cold. Besides that, since you trained so hard to improve your cardiovascular fitness, a 20-minute warm up should do just that; warm you up not tire you out.

Another important race day factor is hydration and nutrition. Poor hydration can play a major role when experiencing arm pump. Caffeine, sugar, and other ingredients in "energy" drinks not only are a symptom of poor nutrition, their ingredients may leave you dehydrated. While these companies make great sponsor for our sport, they are not the best choice on race day if you take your racing seriously. Muscles perform at their best when they are well hydrated and properly "fed." Hydrating the body should be a part of everyday life not something that is achieved in three days or less before the race. There is no substitute for water so drink as much as you can throughout the day, everyday!

Some products, like Moto 911 pain relieving spray, claim that they have the solution to arm pump.

Riding Solutions
Riding technique will also help tremendously. Learning to squeeze the gas tank with your knees will allow you to loosen your grip on the bars. Remaining relaxed on the bike is also a key point. Forearm muscles only get blood flow when they are relaxed, which may explain why some people pump up more on race day than on practice days.

Non-surgical Solutions
Soft tissue treatments such as Myofascial release (of which Active Release or A.R.T. is a form) are often used to minimize adhesions between muscles and their fascia. This helps to. These techniques are uncomfortable, but can be quite effective in improving the mobility of these compartments. To learn more about this technique, contact Dr. Macdonald.

Mental Conditioning Solutions
Dr Cohn, a mental conditioning expert, has put together an audio CD, "Arm Pump Solved: Mental Strategies for Motocross Racers," where he teaches six mental strategies for eliminating arm pump. While he does not disagree that arm pump is a "real" symptom, he believes that the root cause starts in the mind. Dr. Cohn's hypothesis is based on the assumption that if you can ride all day in practice and not get arm pump but pump up in races, then the cause is more mental than physical. If this is happening to you, I recommend checking out the Mental Coaching portion of this website and see if Dr. Cohn can help.

Other Solutions (the power of Placebo)
There is also a class of solutions that I consider to be less effective at reducing arm pump. They include things like suspension set-up, bar position, lever position, grip size, steering dampers, type of bars (anyone remember the bar snake?), seat grippers, and nutritional supplements. This is the point where the science of arm pump management leaves and the art of bike set-up begins. Just remember, the placebo effect can be a powerful tool!

The Bottom Line
In my opinion, there is no magic bullet that will eliminate arm pump, but the three most important things are being in shape, warming up properly at the track, and making sure you are well hydrated on race day. Along with the other suggestions in this article, if you struggle with arm pump, you should be well on your way to eliminating this nemesis. If you take nothing else from this article, remember this; arm pump is linked to your overall cardiovascular fitness so if you are not in top condition for your riding ability, then your chances of getting arm pump are high. And if you are out of shape and battle arm pump, there isn't a pill or surgery in the world that is going to fix your problem.

Dr. Dale Macdonald, a chiropractor and Certified Strength and Conditioning Specialist in private practice in Calgary, Alberta, Canada, certainly has the knowledge and experience to be considered an expert. A former intermediate / local pro motocross racer, he is the Chief Health Care Coordinator of the CMRC Canadian Pro Motocross National Series. If you follow the Canadian Nationals, look for the good Doctor at each and every round. If you have any specific question don’t hesitate to stop by the booth at the track or drop him a line at

That's it for now, until next time, good luck with your training and remember, if you have a question, log on to the Virtual Trainer Expert Forum and have your question answered by a panel of experts. In addition, be sure and check out the Racer X Virtual Trainer archive section. Your complete one-stop information zone for motocross fitness. VT Signature

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  1. Gravatar
    Jesse Nicola November 27, 2011 at 9:40 pm

    Thank you! This was very informative. I'm suffering from arm pump right now and definitely learned a thing or two from this.

  2. Gravatar
    Racer X Virtual Trainer November 28, 2011 at 3:08 pm

    Excellent. Be sure and let us know if you are able to eliminate your arm pump problem!

  3. Gravatar
    Jeremy Parten December 12, 2011 at 1:22 pm

    Thank you! When I was younger and racing I never understood arm pump, but man is it kicking my butt know, I will jump onto these tips right away and see if I can get back into my old racing days.

  4. Gravatar
    Ryno May 28, 2012 at 7:49 pm

    Hey mate,
    Awesome article, one question though...

    I get armpump AFTER my moto (yes i do prefer it than in the moto). Other than stretching it out, raising my arms to let the blood flow out and having my forearms massaged, is there anything else i can do??


  5. Gravatar
    Racer X Virtual Trainer May 29, 2012 at 12:15 pm

    Ryno - Can you do me a favor and post your question on the Virtual Trainer Expert Forum? That way all of the assigned experts on the forum will have a chance to respond to your question. The forum is not like other forums on the internet. Only appointed experts are allowed to respond to questions so you can be sure that your question is answered by a professional in the industry. Thanks and see you on the board!

  6. Gravatar
    Madison October 10, 2012 at 7:54 pm

    Thanks a lot, I am a girl and it is so very embarrassing whenever people see my arm pump. I will definitely use these tips. THANKS!!!!!!!!

  7. Gravatar
    Dan November 12, 2012 at 1:53 am

    i find really rubbing my arms before i ride, like really dig my thumb in till it almost hurts and i find it reduces it

  8. Gravatar
    Racer X Virtual Trainer November 12, 2012 at 9:50 am

    Dan - I'm sure it does. What you are doing is called Myfascial release and it should be a part of every rider's warm up routine.

  9. Gravatar
    John R December 15, 2012 at 2:42 pm

    Dr. McDonald, isn't the ccs more a result of the continued repetition of riding? As a cyclist I've recently had a fasciotomy of my calf (all 4 compartments) to try and relieve my ccs, and seem to have gotten mixed results. That said I certainly wasn't lacking in cardiovascular fitness prior to its onset. My thought is I got ccs through a combination of genetics and poor biomechanics played out over the last 20 years of high mileage training and racing. Could not the same be said of motocross? Another thing which may be of some relief to sufferers would be compression sleeves as seen on some athletes for recovery which may help in expediting blood flow back out of the arm.

  10. Gravatar
    Laura Pons December 18, 2012 at 2:13 pm

    My son was diagnosed with chronic exertional compartment syndrome and he was referred to have faciotomy surgery but the doctor insisted it was carpal tunnel. They ended up doing the carpal tunnel surgery, which caused so much inflammation that it cut off the blood flow to his hand. My question is: if you have chronic exertional compartment syndrome, should you be careful not to cause any trauma to the wrist area so that it doesnt turn into acute compartment syndrome?

  11. Gravatar
    John R December 23, 2012 at 6:46 pm

    Laura, that may be true. From what I've read online in medical studies, it is possible to cause ecs from acupuncture. Wether or not it would cause acute cs in someone who already has ecs I don't know.

  12. Gravatar
    Racer X Virtual Trainer December 24, 2012 at 4:44 pm

    Laura - Please post this question on the forum. Comments to articles on this site are not monitored so there is a chance no one will see your question. Please click on the Forum menu button above and send me an email to join.

  13. Gravatar
    Sawyer June 30, 2014 at 6:09 pm

    I am 14 years old and I deffenitly don't get to ride as much as I want to but on trick I have found to getting rid of arm pump is once I get it I like to go ride a short section of the track for about 15 min straight. This relaxes my arms and after I am able to go back to riding full laps.

  14. Gravatar
    Aaron April 14, 2015 at 8:21 am

    Compression sleeves help with blood flow, thus it should help with arm pump and muscle fatigue.

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