• Welcome to the DeeperBlue.com Forums, the largest online community dedicated to Freediving, Scuba Diving and Spearfishing. To gain full access to the DeeperBlue.com Forums you must register for a free account. As a registered member you will be able to:

    • Join over 44,280+ fellow diving enthusiasts from around the world on this forum
    • Participate in and browse from over 516,210+ posts.
    • Communicate privately with other divers from around the world.
    • Post your own photos or view from 7,441+ user submitted images.
    • All this and much more...

    You can gain access to all this absolutely free when you register for an account, so sign up today!

Question Is being tall advantage or disadvantage?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.

Aljohn

New Member
Jul 15, 2024
4
0
1
21
Hi freedivers! I'm about 6'5 tall, and I want to ask professional freedivers there if being taller has an advantage in freediving dynamic bi fins. Since being tall also means having longer arms and legs
 
Interesting. I have not thought of this and don't really know the answer. But my guess is that being taller would be an advantage. The fastest elite swimmers are taller. I would think it would contribute to "more distance per kick".
 
Reactions: Aljohn
All else being equal, yes - look up Froude numbers and Reynolds numbers (and be prepared for some detailed reading). However, all else is never equal, and there are some very good divers who happen to be short.

In practice it will depend heavily on how you choose to swim/dive, since the advantage enjoyed by taller people is related to drag, which can be increased by poor body shape, wider fin strokes and increased speed. An aside: I'm not sure whether anyone has bothered to determine through fluid mechanics whether finning in bursts is theoretically beneficial, detrimental or neutral. I think that's probably quite a complicated question once the breath-hold is taken into account and may ultimately come down to how a diver feels during their dynamics.

Note that the Froude number relates to wave drag, i.e., to objects travelling along/through/within the surface of a fluid (or the boundary between two fluids - and note that air, as with other gases, is a fluid). However, it also applies to objects in motion in proximity to a surface, i.e., submerged but not very deep. A simple way to think of this is that if the diver is causing the surface of the water to move, they are close enough to it to experience wave drag. That's a nice little experiment for the pool, actually: work out at what depth your dive technique causes wave drag and seek to reduce it.

Sadly for me I am both short and rubbish in the pool. Good luck with your diving.

(Note that I am not a professional diver, but I do know a little bit about fluid mechanics.)
 
Reactions: Aljohn
Thanks for this information
 
Also not a pro diver (and also happen to be a mathematician/physicist with some experience in CFD), but I'd say that unless you're planning to be an elite freediver, pushing your body and diving to its limits, then I doubt it's going to make any significant difference for you personally as long as you don't have some other health/physical issue that might impact your diving in some way.

Yes, longer legs might very slightly increase propulsion per kick, but maybe that could be offset to some degree by the extra torque involved in moving longer legs (so muscles need a little more O2 per kick??) - but it may also be that the most efficient kick has roughly the same amplitude & frequency no matter the length of legs, so...?

I'm pretty sure that many other factors are more important than height/leg-length (e.g. lungs/spleen/dive-response/O2-efficiency/etc.), so it'd likely only start to have a bit of impact at the elite level.
 
I'd guess being longer can be an advantage: Less surface of the body w.r.t to volume, i.e., less drag. Longer sailing boats are typically faster than short ones. On the contrary small persons tend to be leaner than tall ones....
 
Cookies are required to use this site. You must accept them to continue using the site. Learn more…