Forearm Pump (Arm Pump)
Most of us have dealt with it after a hard day of riding or racing – arm pump or forearm pump. Some dirt bike riders seem to get hit with it all the time, others almost never. We’ve looked all over for as many tips as we could find – here are a few that have worked for us and others. If you have any to add, make sure you let us know.

Stretching seems to be one of the best things you can do to avoid or reduce forearm pump. Most racers do some stretching before hitting the track but a lot of trail riders and ditch bangers just hop on and go. Here’s a good forearm stretch. With arms extended in front of you, and fingers straight, pull back on the fingers to flex the wrist joint backwards. Then push on the knuckles to flex the wrist forwards.

Once you’re on your bike, put both hands below the handlebars with your finger tips on the grips and press forwards.

If you’re riding a lot, take time to quickly stretch during the ride.

Loosen up. The tighter you grip, the more it’ll hurt later. That’s why you’ll often find the first ride of the season the most painful as far as arm pump goes – you’re not as relaxed and comfortable on the bike and gripping too tightly as a result.

Ride a lot. Lots of riding not only builds up the right forearm strength, it builds up your confidence and gives you a more relaxed grip.
Exercise. There’s a lot of debate about this one. You hear about riders who go to the gym and still get forearm pump, and then about the skinny, lazy dirt bike riders who never get arm pump. If you’re inclined to try exercise, a squeezable rubber ball, or firm foam ball works well. Another exercise is to tie a weight to one end of a rope and a 1 to 2-inch dowel on the other end. Lift and lower the weight by twisting the dowel, with your arms held as far forward as you can manage.

Get the right gloves, not the tight gloves. You don’t want to restrict blood flow or finger motion.

Brake and clutch levers should be set up so that they’re easy to manipulate while riding. The rule of thumb is to have them in line with your forearms when you’re in the proper riding position.
If you have small hands or short fingers, you may want to try smaller handgrips.

Keep your forearms warm. Too much cool air restricts blood flow and increases the chances of forearm pump.