Editing Snorkeling (section)

===Swimfins===
{{Main|Swimfin}}
Swimfins, fins or flippers are [[fin]]like accessories worn on the feet,<ref name="AlainPerrier" /> and usually made from [[rubber]] or [[plastic]], to aid movement through the water in [[Water sport (recreation)|water sports]] activities. Swimfins help the wearer to move through [[water]] more efficiently, as [[Foot|human feet]] are too small and inappropriately shaped to provide much [[thrust]], especially when the wearer is carrying equipment that increases [[Fluid dynamics|hydrodynamic]] [[Drag (physics)|drag]].<ref name="pendergast2003" /><ref name="pmid15796314" /><ref name="pmid9148086" /> Very long fins and [[monofin]]s used by freedivers as a means of underwater propulsion do not require high-[[frequency]] leg movement. This improves efficiency and helps to minimize oxygen consumption. Short, stiff-bladed fins are effective for short bursts of acceleration and maneuvering. Open-backed fins allow the wearer to wear them over the top of wetsuit socks or boots which can be useful in cooler water.