These days there is a mind boggling array of fins for the diver to choose from. One thing is for certain, a freediver benefits greatly from a long blade fin with a fully enclosed heel.
Long blades produce more thrust for less effort meaning longer bottom times and shorter recovery time between dives. Closed heel (as opposed to open heal SCUBA style) footpockets give a more efficient transfer of energy from the ankle and calf to the blade again resulting in more "bang for you buck".
Footpocket brand is really governed by your footshape and blade by diving style and body strength.
Our good friends at Adreno have an excellent video discussion on how to choose the correct fin for you.
If you've having trouble getting those fancy new blades into footpockets then Adreno can also help with that.
Roy from Agro Dive Imports kindly put this information together for us:
The recent trend towards using higher performance materials like Carbon Fibre, and Fibreglass in fin blade production is causing considerable confusion amongst divers as they renew their fins. Some information to help you select the best fin blade for you follows:
Firstly some misconceptions.
Dropping hard objects onto blades and other such dramatic exhibitions are an improper display of durability, strength, or quality performance. Doing this will cause damage to any blade even if it is not noticeable.
Fibreglass & carbon fibre are very strong materials, but they are not indestructible. They can all be damaged, they will become stressed, they may become prone to osmosis, and they will lose their efficiency over time. They must be well looked after just like any other bit of equipment. They will eventually need replacing, although they will be more efficient for longer than traditional polymer blades.
Carbon Fibre is stronger, technically superior, and more energy efficient than fibreglass as a fin blade material. The efficiency improvement from carbon fibre over fibreglass may only be negligible for a diver of an average standard. Typically, only divers wanting to squeeze every bit of efficiency out of their performance should consider carbon fibre blades.
There are many variables more important in blade selection than the base material. Fin blade design is an essential component of a high performance fin. Essential features are:
A TAPERED BLADE - a blade should taper from the heal towards the tip in order that it develops a smooth consistent curve with a strong recovery memory once flexed.
AN ANGLED HEAL - allows for a natural, more energy efficient kick stroke in both the forward and backward thrust of a kick.
FLEXIBLE SIDE CHANNELS - work a greater amount of water, keep the blade in line, and prevent blade vibration.
BLADE LENGTH is critical to selecting the correct fin.
BLADES OF 80cm+ are more suited to freedivers or spearfishers who dive in a constricted area to great depths (greater than 30m). These blades require a greater level of technique and concentrated effort to achieve a fluid and efficient dynamic motion
BLADES LESS THAN 80cm are more suited to spearfishers that cover large areas and dive repeatedly to various depths. These blades have a sharp, more precise reaction, and they are easier to control and manoeuvre.
BLADE STIFFNESS - possibly the most complicated part of the selection process as there are a number of variables to consider. The objective should be to obtain the greatest possible performance whilst using the least amount of energy; and to also make you, the diver, feel comfortable and safe using it. The softer the blade the less energy required to work it so every diver should select the softest blade possible whilst taking into account their diving style, and psychology.
A large bodied diver may not feel comfortable and safe using a softer blade because it takes a little longer to achieve an acceptable level of momentum on ascent from a dive.
A diver with an aggressive diving style will likely lose patience with a softer blade.
A more technical style diver will achieve improved performance from softer blades.
Footpocket selection is even more important than correct blade selection. If your foot is uncomfortable, then you will be disappointed no matter what you buy.
Rule of thumb:
o Very wide foot = Picasso / Mat Mas Footpocket
o Wide/Medium width foot = Omer / Dessault Footpocket
o Medium Width foot = Esclapez Footpocket
o Medium to narrow Width foot = Spetton Footpocket
o Narrow Width foot = Beauchat Footpocket
As a recommendation when purchasing fins, it would advisable to give preference to a fin with a removable footpocket. This is for two reasons; firstly it is simply a better financial strategy as any keen spearo will almost certainly want to progress to using fibreglass or carbon fibre blades and this way one would only need purchase blades rather than complete fins. Secondly, one would not have to go through the pain of finding suitably comfortable footpockets.