Arm pump takes place when the blood flow entering your arms is greater than the amount of the blood flow out, this creates a backlog of pressure, as well as a lot of pain. Don't worry though, by making a few bike modifications and increasing your motocross fitness, you could be getting rid of arm pump for life!
Luckily, there are a few ways you can try to prevent arm pump:
Although this may seem slightly basic, the logic is not. By riding regularly you are exercising the same muscles that are causing your forearms to pump up during motocross races or practices, as well as increasing your level of motocross fitness. By working these muscles of a regular basis, you will be constantly building their strength and stamina, increasing your level of motocross fitness and decreasing the amount of pain for you, the rider!
Many riders do not realise that most cases of arm pump derive from holding on to tight, rather than their level of motocross fitness. As you can imagine, the scenario here is pretty basic, instead of tightening your grip, focus your brain into allowing you to ride with more flow, and relieving some of the pressure from your forearms. The seat time you build up here will also increase your motocross fitness!
This may seem difficult and believe me it is, as holding on tight is human instinct. Many riders spend short sessions every time they ride literally practicing to relax on the bike, which may sound silly, but you will reap the rewards when arm pump disappears for ever!
Work it out
An important part of increasing your motocross fitness is visiting the gym every now and then. One mistake many motocross riders make when trying to increase their level of motocross fitness is lifting weights that are too heavy. When I say to heavy, I mean for what they are trying to achieve, rather than their capabilities.
Motocross relies on cardiovascular endurance more than anything, faster blood flow and a greater supply of oxygen to muscles, so light weights, running, cycling, jogging and swimming are all good options to increase your motocross fitness. Lifting heavy weights in small sets is training your body to go all out for a short space of time, rather than maintain pace, something you definitely don't want as a motocross rider.
Simple stretches and rotations for your fingers, wrists and forearms can reduce arm pump a greater deal, so ditch the weights!
Personally I have made a few minor modifications to my bike, all aided by trial and error and all have decreased my level of arm pump, even though my motocross fitness has stayed the same.
Seat Cover/Rad Shrouds - My bike now has a seat cover that uses a gripper material. Previously I was using force via my arms and legs to keep myself stable, but I find that the seat cover relieves some of that pressure. The same goes for my radiator shrouds, which have now been fitted with gripper material which comes into contact with my knees.
Suspension set up - While it's nice to blow a few hundred dollars buying graphics plastics and new riding gear, the best money you can spend is setting up your suspension for your size and weight. This is the key to a faster lap time and decreased arm pump, without increasing your motocross fitness!
I have been using a Powerball now for around 2 years; I use it on a daily basis and also use it to as a 5 minute warm up for my arms before riding. Since starting the gym and using the Powerball I have a lot more strength in my wrists as well as a lot less arm pump.
Obviously the Powerball is not perfect, but it has definitely worked for me. (Don't bother with my more expensive versions; they all work in the same way!)
For more hint and tips on how to keep yourself fir for motocross as well as bike maintenance tips, please take a look at Motocross Mania