The diving fins

To be able to swim under water with as little effort as possible, we use diving fins. There are two types of fins; fins with a heel strap and fins with a closed foot section. Both types of fins are available in different sizes, colours and types. The fins with a heel strap are usually used in outdoor water as they are worn with diving socks or diving shoes. Fins with a closed foot section are usually used in the swimming pool and in outdoor water with a pleasant temperature (tropics).

There are fins with relatively long blades which make them particularly suitable for rapid propulsion; a disadvantage, however, is that the use of such long fins can put excessive strain on the leg muscles, causing cramp to occur more quickly. A trained diver, however, will be able to use such fins without any problems.

The requirement for fins

Just like selecting a good diving mask, you need to pay attention to a few things when choosing fins.

The fins should be made of a strong material such as graphite, polyurethane or thermoplastic. Most of these materials are impervious to the effects of sunlight and seawater, which adds to their durability. The foot part should be made of a soft and flexible material like rubber.

The blade of the fins should also be flexible. Fins with an adjustable heel strap are preferable in colder water to fins with a closed foot section. A fin that is too tight to the foot can obstruct the blood circulation resulting in cramp in the foot; while a fin that is too loose will reduce thrust and can quickly be lost. There are also fins with one or more venturi openings, which allow the water to be propelled along the blades in a different way. This gives you more efficiency with less effort.

Fitting of fins

If you need to try on fins with an adjustable heel strap, do so with a diving shoe or sock on. The fins should fit snugly around the dive shoe or sock. Then tighten the heel straps so you can't kick the fins out. Fins with a closed foot area should be fitted without diving shoes or socks. If you put on your fins dry they will be slightly stiff, so put them on wet. Make sure that the fins do not slip when you make a leg turn. All fins should fit comfortably without clenching.