Numb Forearms and Sore Elbows in the Aero Position: Causes and How 3D Lattice Pads Fix Them

The aero position problem nobody talks about

You can have huge engine in your legs, but if after an hour and a half in the aero position your hands go numb, your elbows burn and you have to sit up for air every few kilometres, your time trial or your triathlon bike leg falls apart on its own. The aero position isn't won by whoever gets into it: it's won by whoever can hold it.

And the point where almost everyone breaks isn't the legs or the back: it's the forearm and elbow resting on the aerobar pads. That is where a large part of your weight sits for hours, and that is where a bad pad ruins the experience. In this article we explain why it happens and how we solve it with our 3D lattice pads for triathlon and road aerobars.

Why your arms go numb in aero

Numbness and tingling in the hands and forearms have a very specific mechanical cause: sustained pressure on nerves and blood vessels. In the aero position, much of the weight of your upper body rests on a small surface —the elbow and forearm area— supported by the pad. If that pad concentrates the load on one point, three things happen:

• Nerve compression: the ulnar nerve, which runs near the elbow, gets compressed and the classic tingling towards the ring and little fingers appears.
• Reduced blood flow: constant pressure restricts circulation and the arm "goes to sleep".
• Muscle fatigue: because you can't relax on the rest, the stabiliser muscles overwork and you end up shifting around, losing aerodynamics.

It is the same mechanism that causes numb hands on the handlebar, just moved to the forearm. And the conceptual solution is identical: spread the pressure instead of concentrating it.

Where traditional EVA foam fails

Most aerobars come from the factory with simple EVA rubber or foam pads. At first they seem comfortable, but they have two underlying problems:

1. They sink and "bottom out"

The foam compresses under your weight until it stops cushioning: there comes a point where you feel the rigid base of the bracket through the pad. The longer the effort, the sooner it happens. And over time the foam packs down and loses its rebound, just as happens to a foam saddle.

2. They spread load poorly and don't breathe

A uniform foam doesn't distinguish between the area where your elbow bone rests and the area where your forearm lies: it cushions the same everywhere. And being a closed material, it traps sweat and heat exactly where it feels worst during a hard effort in the sun.

The alternative: 3D lattice pads

Our large-format pads aren't a block of foam with a nice shape: they are a 3D-printed lattice structure, made with Carbon DLS technology and EPU elastomeric material. Instead of a solid material, they are a three-dimensional network of hollow cells that behaves very differently.

Variable density: firm and soft at the same time

By designing the geometry cell by cell, we can make the lattice softer where you put your weight (to absorb vibration and pressure) and firmer at the edges (to give you stability and control). Foam can't do this: it is the same throughout its volume. A 3D lattice can.

It doesn't bottom out or pack down

The lattice structure recovers its shape again and again and doesn't compact with use like foam. That means the pad that gives you comfort at kilometre 10 still gives it to you at kilometre 90. Hour 4 feels like hour 1.

Real breathability

Because it is an open structure, air circulates through the lattice. It doesn't trap sweat or heat like a closed foam, a detail you really appreciate in long-distance triathlon and on hot days.

More support surface

A pad with a larger contact surface spreads the same weight over more area: pressure per square centimetre drops and you relieve tension in your neck and shoulders. Fewer hot spots, less need to reposition. (And if you race on a time trial bike, there is also a large-format version designed specifically for TT base bars.)

Biocompatible and hypoallergenic

The EPU material of the lattices is biocompatible and hypoallergenic, designed for prolonged contact with the skin without irritation. It is the same type of material and process we use in our NEXUS 3D saddles and our Race Days grips: high-performance contact technology applied to every point where your body touches the bike.

3D lattice pads at a glance

How to tell if you need them

If you recognise yourself in any of these situations, the problem is almost certainly your rest:

• Your hands go numb or your fingers tingle after a while in aero.
• Your elbows or forearms hurt and you have to sit up to rest.
• You can't stay still in the position: you keep repositioning.
• You notice the original pad "bottoms out" on long rides.

Changing just the pads is by far the cheapest and highest-impact comfort upgrade you can make to your aero setup, without touching the bike or the handlebar.

Frequently asked questions

Why do my arms go numb in the aero position?

Because the weight of your upper body falls on a small surface at the elbow and forearm. That sustained pressure compresses the ulnar nerve and reduces blood flow, and tingling and numbness appear. Spreading the pressure over a larger surface reduces or eliminates the problem.

How are they different from EVA foam pads?

Foam cushions the same throughout its volume, sinks until it bottoms out and packs down with use. The 3D lattice has variable density, recovers its shape without compacting and breathes because it is an open structure.

Are they compatible with my aerobars?

They are designed for CarboXtrem triathlon and road aerobars (clip-on). If your bike is a time trial bike with a TT base bar, there is a dedicated large-format version. If you have any doubts about your setup, message us and we'll confirm.

What material do they use and is it safe for the skin?

They are 3D printed in EPU material using Carbon DLS technology. It is biocompatible and hypoallergenic, designed for prolonged contact with the skin.

Hold the position, win the race

A very aero position is no use if you can't hold it. If your hands go numb or your elbows hurt on every long ride, your pads are the weak link. Swap them for 3D lattice pads and discover what it's like to ride for hours in aero without thinking about your arms.

Discover the 3D Lattice Aerobar Pads →