Eliminate Arm Pump & Avoid Hand Fatigue When Mountain Biking

Sore hands and tight forearms are very common issues for mountain bikers since often the weight distribution is towards the handlebars. Especially when riding downhill sections hands are tasked with high loads and impacts. But even on long rides with harsh impacts, hand fatigue can be prevented or at least reduced by anyone.

To avoid hand fatigue and arm pump when mountain biking, loosening the grip on the handlebars is vital. For this, body position has to be good and the grips and brake levers must be set up well. Additionally, nothing helps more than comfort, and self-confidence on the bike, which comes from practice.

Your hands are vital contact points to the bike, responsible for turning, braking, stability and actually staying on the bike. Naturally, they get tired from time to time. And if your hands get so tired that you can’t even grip the handlebar or brake anymore, the joy of riding is lost.

By the way, here I will not be going into how to prevent hand palm blisters from mountain biking. That’s a separate issue with different (and some overlapping) reasons than sore hand and arm muscles.

Arm pump and hand fatigue basically occur for the same reasons: Strenuous grip for long periods of time. The muscles responsible for tightening the grip of your fingers are located in the forearm. They get pumped with blood to provide oxygen and that swelling of the muscles also leads to blocked blood flow, which in turn leads to numb and powerless hands, making it difficult to brake, steer the bike or even hold on.

But there are ways to ride all day – long pain-free and full of energy.

Bike fit & saddle position

The saddle position may be overlooked here often when it comes to strain on the hands. But your butt is actually there to carry the majority of the weight. When it doesn’t the arms and hands get worn down more than necessary.

Sometimes if the saddle nose is tipped down, your weight gets distributed towards the front and you place too much weight on your hands. Similarly, sliding off the back of a saddle pointed up, requires holding onto the handlebar all the time. You should be able to take your hands off the bars and support yourself with your core and legs only.

Your hands make up pretty much half of the contact points with your bike. Like with the feet, a good connection and positioning are required for good feedback and controllability. Furthermore, hand positioning and grip translate through the whole upper body and overall body position.

For downhill riders, all information in this article is even more relevant with the load put onto the hands and arms when pointing down a steep track and through turns.

Cockpit setup

By cockpit, bikers mean the assembly of everything connected to the handlebar, like brakes, grips, shifters, a dropper post remote, and the stem. The first three of those have a direct tangible impact on hands and in turn body position.

Everything in the cockpit relies on a good handlebar position or bar roll and the correct handlebar length. Everybody’s upper body is sized differently and handlebars are not entirely straight. So adjustment is needed. When viewed from the side, the handlebar should point in the same direction as the fork stanchions, and by extension your forearms when in the riding position.

Brake lever angle dictates how the hands and arms are positioned. What you want is a strong in-line position of hand, wrist and forearm like you would have doing a bench press to be able to use all your upper body strength.

Softer grips with the right diameter

Of course, the bike part actually connected to both hands has a big role in how your hands feel. I’ve had a number of different MTB grips over the years. from minimal slick race grips for maximal feedback, to fully ergonomic ones, to now padded offset-design ones.

Thinner but harder grips are preferable for direct feedback and control but are also harsh on the hands. On the flip side, big chunky grips are softer due to more rubber material but are also difficult to grip with smaller hands. But there is actually a choice here, no matter the hand size thanks to creative offset designs like from the American grip brand ODI.

Among other models, they make the “Aaron Gwin” signature line of grips. The newer AG2 grips, which I run on my downhill bike, are designed in a way to feature maximal padding for a given diameter – combining control with comfort.

One other aspect of MTB grips to look at ist the surface. Similar to the tread pattern of an MTB tire, it’s designed to provide actual grip to the grip. More “mechanical grip” between glove and grip means less energy required by the rider.

Suspension setup

Correct fork and damper setup are fundamental not only for handling but also for efficiency.

Bad suspension settings lead to many more problems like harsh feedback through the handlebar, hand fatigue, arm pump and of course more energy required to stay on the bike.

Harsh-feeling suspension can have two major reasons: slow rebound or too much compression. The former has the suspension not rebound with subsequent impacts, while the latter doesn’t compress enough. Both ends of the spectrum feel violent because the suspension isn’t working at all, not utilizing its full travel.

Missing balance between fork and damper can also lead to tiring riding. Like when the fork is dramatically softer than the rear suspension, sending the center of gravity and more workload to the front and your hands.

Tire pressure

Pump up the tires to the ideal tire pressure, which usually is lower in the front than the back tire. Too high pressures have many negative impacts like harsh feedback and reduced damping. Check out a full PSI chart here and get to know why tire pressure matters so much here.

Line choice

How active you have to be on the bike not only depends on the track difficulty but also on the actual line you pick on it. Bike park tracks are usually a couple of feet wide, while you actually only require a tire width on them. Choose where you put your tires consciously.

By picking smoother, creative lines with less big compressions and bigger corner radius’ you can make a rough natural track not as physically demanding.

And on the other hand, a mellow line can (and often does) have loads of braking bumps that will vibrate your hands off the handlebars when riding those all day.

Most of the time, there are less-abusive lines further to the edges of a trail or can be done creatively by pumping and jumping.

Pause regularly and pace yourself

Don’t overdo it, if riding long is the goal. That is applicable for individual laps and for entire days.

If you go all out on one lap, the next might be lacking concentration or strength. Same with a full day of full-throttle riding. Great, give it your all if you plan on resting the following day. But it’s not such a hot way to start out on a multi-day trip.

Exercise & training

Why train? Mountain biking is hard enough as it is. And counts as exercise anyway.

That’s what keeps me coming back to the gym to pick up some heavy objects. And I can’t overstate the positive effect that’s having on my riding and overall well-being. I even created a mountain biker’s training guide for gym muffs and gym rats where I share the exercises and routines I myself do to prepare for the MTB season as an amateur rider.

I value a balanced workout routine, but specifically for grip strength, my favorite exercises are kettlebell swings, deadlifts, pull-ups, power cleans, farmers walks, and inverted rows.

Time in the saddle

It’s a cliche to say nothing beats time on the bike. And that’s because there’s truth to that statement. And only partly because of the physical aspect. It’s a mental thing too.

Even with your bike setup and body position dialed, if your head is not in the right space, your body will tense up. This can be for a lack of comfort, riding unknown trails, riding scary features, difficult tracks, no warming up and generally being out of your comfort zone.

Being completely off a bike for a couple of weeks or swapping between two is usually enough to lose some confidence. Only with comfort on the bike can you know when to grip hard and when you can let loose a bit and rest your hands. Uncomfortable or inexperienced riders tense up for the entire time, instead of for the few times a tight grip is actually needed.

The tension of your body should come from your core and legs, not your arms and hands. But keeping your arms and hands light and loose is easier said than done. There is no way around actual time in the saddle and getting familiar with your equipment and the trails.

It’s not a fast solution, but the best long-term hack against sore hands.