by Nick Lakoff, Scuba Instructor
As a diving instructor I have used all sorts of fins in all sorts of conditions but my observation over the years have led me to conclude that it’s more how they are used that determines how proficient your are underwater. Finning is very important in diving with regard to the economy of energy and streamlining in the water. Our legs are part of the strongest muscle groups we have in the body and combined with fins they give us a method of propulsion underwater that requires less energy than using our arms. As you may know, using your arms waste energy and destabilizes your diving profile. Ideally a diver uses their legs for most if not all maneuvering motions. Mastering fining techniques really makes you stand out as a diver and makes it more enjoyable for others. There is nothing more annoying that following someone through a swim through or in a sandy patch and they are stirring up the silt. This is especially true if you have photographers in the group. When the silt is stirred up you’ve essentially ruined their photo ops in that area and there is rarely enough time to wait for it to settle down.
There are four types of kicks used when fining underwater. The first is the straight kick which is the main method used while swimming underwater. The most important characteristic here is keeping the leg straight with a slight bend in the knee. So often I see people bending too much and even doing a motion akin to riding a bicycle. If you keep your legs as straight as possible you will use less energy. When away from corals or the bottom use strong strokes keeping your feet pointed. When using this kick close to the bottom you don’t need to kick so hard since doing so will still up the sand and silt. The power comes from the thighs and should be short but not too strong. If you are close to the sandy bottom you can look back to see if you are stirring up silt. Its good to practice hugging the bottom to perfect this skill.
The second technique is the frog kick. It is very similar to the breaststroke kick for those who are familiar with swimming strokes. The knees are bent and the lower legs are turned in a circular movement towards the inside. This is a great technique for large horizontal openings with low overhead obstructions. Be conscious that your profile is now not as streamlined and this stroke is designed for slow cautious movement.
The third stroke is the crossover which is great for very narrow passages like a swim through. You place one fin over the other and kick keeping the legs in a crossed position. This is also a slow speed kick and is meant to reduce kicking up silt and disturbing marine life and/or hang-ups.
The fourth kick is not used as often but I like to use it when I have some ground to cover quickly and as a way to alternate strokes in order to prevent cramps. The mermaid stroke is created by placing your legs together and kicking both legs at the same time while undulating your body. In effect it’s as if you had a mermaids tail. You can get some serious speed doing this but be conscious that it requires lots of energy and therefore your air consumption will increase.
Learning to master fining goes a long way to improving your comfort in the water. It will allow you to enjoy your dive and help with buoyancy. It comes in very handy when doing specialty like Digital Underwater Photography, Deep Diver and Wreck Diving. Some dive operations will not allow you to penetrate some wrecks even if you are wreck qualified unless you can demonstrate proficiency in fining. In these restricted environments stirring up the silt can severely restrict visibility and endanger others as well as yourself.