Years before scuba was invented, freedivers and underwater hunters used fins with mask and snorkel to increase their range, get down to depth more quickly, and provide bursts of speed as needed. Fins were created after observing the water-propulsion effectiveness of web-footed animals, such as ducks and frogs. In fact, many early fins were nearly exact copies of a frog’s fins – probably one of the reasons that early military scuba divers were nicknamed “frogmen.”
Fins make swimming with foot-propulsion much easier, much more effective, and considerably more enjoyable. And because scuba divers are not only pushing themselves through the water – they are pushing their gear, as well – fins have been a part of scuba equipment since Day 1. Actually, since almost all of the early scuba divers were freedivers or snorkelers first, fins have been part of scuba since before Day 1.
Years before scuba was invented, freedivers and underwater hunters used fins with mask and snorkel to increase their range, get down to depth more quickly, and provide bursts of speed as needed. Fins were created after observing the water-propulsion effectiveness of web-footed animals, such as ducks and frogs. In fact, many early fins were nearly exact copies of a frog’s fins – probably one of the reasons that early military scuba divers were nicknamed “frogmen.”
Fins make swimming with foot-propulsion much easier, much more effective, and considerably more enjoyable. And because scuba divers are not only pushing themselves through the water – they are pushing their gear, as well – fins have been a part of scuba equipment since Day 1. Actually, since almost all of the early scuba divers were freedivers or snorkelers first, fins have been part of scuba since before Day 1.
If you’ve ever swished your hand through a tub of water (to swirl in some bath salts, for instance), you’ve undoubtedly noticed that water provides resistance to anything moving through it – you can feel the water “pushing back” against your hand.
It’s this push-back that provides much of the propulsion created by a moving fin. Just as the sole of your foot encounters resistance (and thus creates propulsion) when you swim, fins encounter resistance and create propulsion as well. But fins work better than bare feet because their surface area is larger (thus encountering more water for that critical resistance), and – on most modern fins – the undulating motion of the fin provides resistance in both motions of the kick cycle (i.e., the up-motion power stroke as well as the down-motion return stroke, when the fin acts like a scoop being moved through the water).
Physics dictates that the direction of your travel will be the exact opposite of the direction in which you are pushing the water. Because of this, fin manufacturers have paid lots of attention in recent years to channeling – how the fin focuses the direction in which the water is moved. Many manufacturers have also focused on engineering fins that have extremely flexible web sections, split fin construction, and other advantages. All of these are designed to reduce the amount of energy required to move through the less-effective return stroke of a kick cycle, while preserving a great deal of effectiveness on the power stroke.
If you’ve ever swished your hand through a tub of water (to swirl in some bath salts, for instance), you’ve undoubtedly noticed that water provides resistance to anything moving through it – you can feel the water “pushing back” against your hand.
It’s this push-back that provides much of the propulsion created by a moving fin. Just as the sole of your foot encounters resistance (and thus creates propulsion) when you swim, fins encounter resistance and create propulsion as well. But fins work better than bare feet because their surface area is larger (thus encountering more water for that critical resistance), and – on most modern fins – the undulating motion of the fin provides resistance in both motions of the kick cycle (i.e., the up-motion power stroke as well as the down-motion return stroke, when the fin acts like a scoop being moved through the water).
Physics dictates that the direction of your travel will be the exact opposite of the direction in which you are pushing the water. Because of this, fin manufacturers have paid lots of attention in recent years to channeling – how the fin focuses the direction in which the water is moved. Many manufacturers have also focused on engineering fins that have extremely flexible web sections, split fin construction, and other advantages. All of these are designed to reduce the amount of energy required to move through the less-effective return stroke of a kick cycle, while preserving a great deal of effectiveness on the power stroke.