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what's your ape index?

have you ever considered how you body type might effect how you should swim?


The length of your arms relative to your height can have a big effect on your swimming. In the rock climbing world this is known as your 'Ape Index' and is normally expressed in inches. So if your arm span is two inches wider than your height, then that gives you an ape index of +2. If your arm span is 3 inches less than you stand tall then your ape index is -3.

It's very easy to quickly find your ape index: stretch up against a wall or post and just touch the ground with the fingertips of your middle finger. Then stretch up as high as you can with the other hand. Keeping your top finger in place, stand up and compare it to your height. You don't have to be too precise with this, you can look at the difference and estimate it in inches:


We can see here that Paul has an Ape Index of about +3.

But what's this got to do with swimming? If you have short arms for your height (an ape index of zero or less) it's very unlikely you will be able to make a long stroke style work for you. Swimmers with short arms will become slower and less efficient by trying to match the strokes per length of long-armed swimmers - it simply doesn't suit them.

If you have shorter arms don't despair, you are capable of swimming at a higher strokes per minute ("stroke rate") than other swimmers without fighting the water. A shorter stroke with a faster turn-over is your route to swimming speed and efficiency. Copying the style of elite swimmers (who nearly all have long arms) really won't help much.

You might want to think about arm length like crank length on bikes: cyclists with shorter femurs tend to favour a shorter crank length that allows them to turn their legs over faster. It's really the same principle here with swimming.

Swimming With Shorter Arms

If you have shorter arms, it's worth watching this clip. Hannah's an intermediate level swimmer, swimming around 1:40/100m pace :

Hannah's not an advanced or elite level swimmer but the same principle applies for this level of swimmer too: a higher stroke rate style is essential.

At Swim Smooth we think there are two ideal styles of stroke, the Smooth style and the Swinger style. The Smooth style is what most people think of to be an efficient stroke - swimmers such as Ian Thorpe and Michael Phelps use this style: www.swimtypes.com/smooth

However, a shorter faster stroke can be equally quick, especially when combined with a two beat kick - we call this the 'Swinger' style because the arms tend to come around the side.

Swimming legends such as Janet Evans, Shelley Taylor Smith and Laure Manadou used this stroke style to devestating effect, winning Olympic Golds and World Championships, and setting World Records with it. Find out more about the Swinger style here: www.swimtypes.com/swinger


If you have short arms don't despair, you can swim just as fast as anyone else when you've adopted a stroke style that suits you.
Besides, our ape ancestors had very long arms, which must mean you're more highly evolved! :)

swimming with long arms

If you have long arms relative to your height then a long smooth stroke style probably suits you best. However, be careful not to overdo this and try and add glide into your stroke. By gliding you create a deadspot or pause which makes you inefficient. It also tends to harm your catch because you have to hurry it to get your stroke going again. The true Smooth Swim Type doesn't pause in their stroke, they keep that lead hand constantly in motion, taking longer over the catch phase of the stroke than an Overglider.

Further Thoughts

Ape Index is just one of the many physical and psychological attributes that make up your swimming individuality. If you've found that following a particular piece of swimming advice hasn't improved your speed (or even made you slower) then question if this was good advice for your stroke.

Remember: the biggest misconception in swimming is that everyone should try and swim the same way!

Tell Us About Yourself!

If you have an ape index greater than +5 or less than -4 inches then we'd love to hear about your experiences of swimming and the stroke style that works for you. Send us a quick email to: feedback@swimsmooth.com

If you have any video clips of your stroke we'd love to see those too.

Info on ape index in Wikipedia here.

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Swim Smooth Links

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all about front crawl breathing here.
tips on triathlon swimming for you.
get a better front crawl catch and swim quicker.
all about swimming technique in your language.
all about freestyle technique to swim faster.
kick ass triathlon training plan for you.