Thumb catches: how your thumb turns a bad hold into a good one

The finger nobody uses

Watch most people climb and their thumbs are just along for the ride. Four fingers on the hold, thumb tucked away or waving in the air. On big jugs that is fine. On anything small, flat or awkward it means you are climbing with eighty per cent of your hand.

A thumb catch is any time you put the thumb to work: hooked under a ripple, pressed against the side of a hold, or wrapped over your own finger. It rarely turns a terrible hold into a jug, but it often turns a hold you can only touch into one you can actually move off.

Where it turns up

Pinches. The obvious one. A pinch is a hold you squeeze between thumb and fingers, so the thumb is doing half the job by definition. If the thumb side feels bad, you are usually squeezing with the fingers and only resting the thumb there. Pinch strength covers how to build the squeeze itself.

Crimps with something underneath. Look below a small edge before you pull on. Very often there is a little bump, a seam or the bottom of the hold itself where the thumb can sit. Even a few millimetres of thumb gives the hand something to pull against.

Slopers and rounded tops. On a sloping hold the thumb can press in from the side or underneath and stop the hand rolling off. It turns a pure friction hold into something closer to a pinch.

Sprags. On gritstone and sandstone you often meet two features close together, like the sides of a pocket or two little edges. Fingers on one, thumb on the other, pushing them towards each other. That opposing pressure is called a sprag, and it can hold a surprising amount.

The thumb lock on a crimp

There is one more way to use the thumb. In a full crimp you can wrap the thumb over the top of your index finger and press down. It adds real strength to a small edge, and plenty of strong climbers use it on the hardest moves.

It also puts a lot of load through the finger joints and pulleys. Save it for the one move that needs it rather than every edge on the problem, and only once your fingers are properly warm. Crimp grips explained goes through when each grip makes sense.

How to set a good thumb

Look before you grab. Most missed thumb catches are simply not seen. Before a hard move, run your eyes round the hold for anything the thumb could use. If you are working a problem, do it from the ground between goes.

Place the thumb first on a bad hold. On a pinch or a poor crimp, set the thumb, then bring the fingers down to meet it. Doing it the other way round leaves the thumb wherever it lands.

Press, do not just rest. The thumb only helps when it pushes. Squeeze towards the fingers on a pinch, push up from underneath on a crimp, press in from the side on a sloper. A thumb that is touching but not pressing does nothing.

Keep the wrist in line. A thumb that is twisted round at a strange angle tends to slip and can strain the base of the thumb. Turn your body or move your elbow so the thumb pushes in a straight line.

Chalk it. People chalk their fingertips and forget the thumb. A sweaty thumb pad slides first, and the whole grip goes with it.

When it goes wrong

The thumb slips as you move. Your body is moving away from the direction the thumb pushes. Keep your hips close to the hold until you have the next one.

The base of the thumb aches. Usually from cranking hard sprags or wide pinches cold, or from the wrist being bent sideways. Warm up on bigger pinches first and back off if it stays sore.

It feels like it makes no difference. On some holds it will not, and that is fine. The habit is checking. You are looking for the one hold in five where it changes everything.

Drills that make it stick

Thumbs-only lap. On an easy circuit, make a point of finding something for your thumb on every hand hold. It feels forced at first, which is the point. You will start seeing thumb catches you walked past for months.

Pinch traverse. Traverse a section of wall using only holds you can pinch. Easy angle, big holds, lots of moves. It builds thumb strength and the habit of squeezing.

Same hold, two ways. On a crimp with a thumb catch, try hanging it for a few seconds with the thumb tucked away, then with the thumb pressing. Feel the difference while your feet stay on.

Hunt it on your project. Next time you are stuck on a move, go back to the hold you are leaving and the one you are going to and look only for thumbs. It is one of the quickest bits of beta to find.

Cold rock, better thumbs

Autumn is when grit and sandstone come into condition, and friction season is where thumb catches shine. Cold rock makes small ripples and sprags feel far more positive than they do in summer. The flip side is numb hands, so keep them warm between goes or the thumb loses feel first.

The short version

A thumb catch puts the fifth finger to work. Look for something under, beside or opposite the hold, set the thumb first on bad holds, press rather than rest, keep the wrist in line and chalk the thumb as well as the fingers. Save the full crimp thumb lock for the move that really needs it.

Small grip changes like this are easy to forget by next week. Sendit lets you keep beta notes and video with every attempt, so the thumb catch that unlocked the move is still there when you come back to it.