Welcome to Part Eighteen of The Beginner’s Guide to Freediving, the best place to start your freediving journey. If you’re planning to start freediving, this chapter is all  about about the monofin. It looks at the history of the monofin, construction and different types. Also using a monofin for freediving; how to train with one and how to select the right one for you.

The Freediving Monofin

In the 1990s, very few freedivers were using a monofin for freediving – it was a rarity in international competitions. Fast forward to today and it is bi-fins that are the rarity. It’s easy to see why: Monofins enable freedivers to dive deeper in open water and longer in the pool, and mastery of the technique gives you incredible confidence and power.

This article will look briefly at the history of the monofin, the design and construction of monofins and how to choose one that is right for you. It will also cover how to perfect your monofin technique, and includes exercises you can do both in and out of the water.

Beginners guide to freediving Using a monofin for Freediving Aolin Wang from China diving with a Monofin at Vertical Blue 2016 (photo by Daan Verhoeven)

Aolin Wang from China diving with a Monofin at Vertical Blue 2016 (photo by Daan Verhoeven)

Using a Monofin for Freediving – Origin of the Monofin

Humans have always had an affinity with dolphins, and the mythology around mermaids links into this desire to emulate the tail movement of dolphins and whales. In 1971 a Russian woman called Svetlana Uspenikaia arrived at the European Fin-swimming Championships with a monofin she had constructed from two titanium branches, joined together by a ‘sail’. She blew the competition out of the water and the next year the Russian team all arrived with monofins.

It took a while for freediving to embrace the monofin, especially as at the time freediving records were few and far between and mainly based around the No Limits discipline. But in 1992 Rossana Majorca used a monofin to dive to 58m and the freediving world began to take notice. Monofins are now widely used for the pool discipline of dynamic with fins, constant weight freediving and variable weight diving. When used correctly, the monofin is much more effective for long and deep freediving than bi-fins, enabling you to feel a little bit more like our aquatic relatives in the water.

Using a Monofin for Freediving – Construction and Design

The basic monofin design is a pair of foot pockets attached to a single blade, however these individual components vary considerably in terms of design and construction.

With any fin, you want the best transfer of power from your body to the blade. This transfer of power relies most on through having a foot pocket that fits tightly on your foot. If you compare scuba fins, which are worn with a boot and heel straps, with a freediving bi-fin foot pocket, you will see that the tighter fit around the freediver’s foot enables a better transfer of the power that the diver’s leg produces.

There are many monofins on the market that take regular bi-fin foot pockets and attach them to a monofin blade. This has an advantage in that it is more comfortable to wear, however there are some disadvantages. Firstly, there will be more movement inside the foot pocket and a corresponding reduction in transferable power. Secondly, separate foot pockets can cause cracking or splitting of the blade between the foot pockets, as they are able to move slightly independently, stressing to the blade. Thirdly, with the use of bi-fin foot pockets it is not possible to adjust the angle of the blade relative to the body, which increases resistance in the water. Fourthly, it is not easy (and to my knowledge no-one has even done this) to cover the foot pockets and make them more streamlined where they meet the blade.

Monofins were initially developed solely for use in the sport of fin-swimming, where swimmers swam short distances and were not expected to spend a long time in the water. As a result, the foot pockets were very tight and could only be worn for a matter of minutes before becoming extremely painful to wear. There has been some evolution in the monofin market to address this with some companies inserting a layer of neoprene inside the foot pocket, but most monofin manufacturers do not offer this, instead suggesting you specify a larger foot pocket if you want more comfort or to wear the monofin with neoprene socks.

These foot pockets are usually made from a single mold that glues to the fin, thus reducing the risk of cracking from the use of two bi-fin foot pockets. It also enables the foot pockets to be built up, minimizing water resistance as it moves over the blade, along the feet and then the body.  The materials used to create these foot pockets vary but are usually made from rubber, neoprene or sometimes plastic.