Calculate Your Ape Index

When struggling on a route or boulder, excuses are always welcome. ‘Too reachy’ or ‘too bunched’ are both excellent excuses when applied correctly.

The next level excuse is taking the perceived disadvantage and applying it not one boulder, but to all of them. Here, the Ape Index provides the perfect pseudo-scientific excuse. But what is the ideal body type?

What is the Ape Index?

The Ape Index describes the ratio of arm span and body size. The concept was founded by the climbing scene, but has since made its way into a number of scientific papers.

Generally speaking, humans have evolved relatively symmetrically; Our feet are around as long as our forearms, our eyes lie in the middle between chin and the apex of the forehead - and our arm span corresponds to our body size.

The theory of the Ape Index now states that people who have a particularly wide span have an advantage when climbing - similar to our distant relatives, the apes.

What is a good Ape Index?

As already mentioned, a particularly high span should theoretically have an advantage. This means that the arms should be longer than the total body height. Using the Division method, any value above 1 is positive, and with the Subtraction method, the bigger number the better.

Is a positive Ape Index a real advantage?

Now comes the bad news: scientific study finds no concrete link between ape index and climbing performance. Studies have shown that this also applies to dynamic moves - so says German Wikipedia. English Wikipedia, on the other hand, introduces scientific examples which are supposed to have found evidence of an advantage. Opinion stacks against opinion, and the discussion around Ape Index as a legitimate excuse for bad climbing continues.

However, all of them agree on one thing: gear, flexibility, strength and experience all play a decisive role in climbing and bouldering. If you don’t train, you’ll get no benefit from your fabulous Ape Index ;-)

How is the Ape Index calculated?

Division: This variant is the more common and also the one that has been scientifically mentioned. The formula for calculation is as follows:

Ape Index = Arm Span ÷ Body Height

Subtraction:The faster version that can be taken easily on many occasions. The formula for calculation is as follows:

Ape Index = Arm Span - Body Height