I am a finned swimming instructor.
In finned swimming competitions (and in underwater velocity competitions, which is finned swimming with a small scuba tank) the athlet must attain maximum speed for significantly long times, so they want not only an high speed, but also an high efficiency.
If you look at their fins, they are typically monofins, long and "properly" flexible, built in low-loss elastic materials such as carbon fiber.
Each human is different, hence there is not a fin which is ideal for all. Everyone needs to find (or, better, to build) fins perfectly suited to his legs.
The three main parametrs are length, stiffness and angle between the sole and the blade.
After months or years of training, these parameters change, allowing for longer, stiffer fins, and reducing the angle.
Top athlets often need a negative angle (the blade coming up instead of being angled down).
Of course using long fins of proper stiffness require an efficient kicking style, which synchronizes with the natural resonance frequency of the fin.
This is more easy to obtain using a dolphin kick, bringing the fins into resonance using a flutter kick is feasible, but more difficult to obtain.
In any case the knees must be kept almost perfectly straight, people who flex their knees loose thrust and efficiency.
When I was working as a dive master at Maldives I was not allowed to use a monofin. So I did employ freediving fins, having chosen them with proper length and stiffness for being used with my medium-grade drag setup (15 liter steel tank, horse-collar BCD and 3mm fabric-covered neoprene suit). This allowed me to being able to swim against the strong current in the Maldives' channels for short periods.
But my wife, who is also a finned swimming instructor and uses much less air than me, was instead using top-length and very stiff freediving fins, with a 10 liters tank, no BCD and no diving suit.
This allowed her to reach even higher speed and to sustain it for longer periods.
In fact it was her task to savage customers ripped away by the current...
All that said, if you plan to dive often in strong currents, you should take a number of actions:
1) minimize drag, leaving on boat all the equipment you do not need, wearing a very streamlined suit with smooth external skin (or no suit), using a very small rear BCD-wing (or no BCD) and streamlined harness and equipment.
2) experiment with a number of different fins, trying to find, for each of them, the proper kicking style and kicking pace.
3) hire a finning instructor (I do not know if finned swimming is a sport usually practiced in the diving clubs of your town) and get trained to proper finning methods, including dolphin style, which is the faster and more powerful.
4) for maximum performance evaluate the usage of a monofin. This takes away a lot of control, so it requires advanced body and arms handling. Usually you find that girls who have years of experience in synchronized swimming, or having worked as mermaids, can handle well to use a monofin during general-purpose scuba diving.
In finned swimming competitions (and in underwater velocity competitions, which is finned swimming with a small scuba tank) the athlet must attain maximum speed for significantly long times, so they want not only an high speed, but also an high efficiency.
If you look at their fins, they are typically monofins, long and "properly" flexible, built in low-loss elastic materials such as carbon fiber.
Each human is different, hence there is not a fin which is ideal for all. Everyone needs to find (or, better, to build) fins perfectly suited to his legs.
The three main parametrs are length, stiffness and angle between the sole and the blade.
After months or years of training, these parameters change, allowing for longer, stiffer fins, and reducing the angle.
Top athlets often need a negative angle (the blade coming up instead of being angled down).
Of course using long fins of proper stiffness require an efficient kicking style, which synchronizes with the natural resonance frequency of the fin.
This is more easy to obtain using a dolphin kick, bringing the fins into resonance using a flutter kick is feasible, but more difficult to obtain.
In any case the knees must be kept almost perfectly straight, people who flex their knees loose thrust and efficiency.
When I was working as a dive master at Maldives I was not allowed to use a monofin. So I did employ freediving fins, having chosen them with proper length and stiffness for being used with my medium-grade drag setup (15 liter steel tank, horse-collar BCD and 3mm fabric-covered neoprene suit). This allowed me to being able to swim against the strong current in the Maldives' channels for short periods.
But my wife, who is also a finned swimming instructor and uses much less air than me, was instead using top-length and very stiff freediving fins, with a 10 liters tank, no BCD and no diving suit.
This allowed her to reach even higher speed and to sustain it for longer periods.
In fact it was her task to savage customers ripped away by the current...
All that said, if you plan to dive often in strong currents, you should take a number of actions:
1) minimize drag, leaving on boat all the equipment you do not need, wearing a very streamlined suit with smooth external skin (or no suit), using a very small rear BCD-wing (or no BCD) and streamlined harness and equipment.
2) experiment with a number of different fins, trying to find, for each of them, the proper kicking style and kicking pace.
3) hire a finning instructor (I do not know if finned swimming is a sport usually practiced in the diving clubs of your town) and get trained to proper finning methods, including dolphin style, which is the faster and more powerful.
4) for maximum performance evaluate the usage of a monofin. This takes away a lot of control, so it requires advanced body and arms handling. Usually you find that girls who have years of experience in synchronized swimming, or having worked as mermaids, can handle well to use a monofin during general-purpose scuba diving.
