Monofin

From Wikipedia, the free encyclopedia

A freediver using a monofin
A freediver using a monofin

A monofin is a type of swimfin typically used in finswimming and free-diving. It consists of a single surface attached to footpockets for both the free-diver's feet.

Monofins can be made of glass fibre or carbon fibre. The diver's muscle power and swimming style, and the type of activity the monofin is used for, determine the choice of size, stiffness, and materials.

The monofin swimmer extends arms forward, locking hands together, locking the head between the biceps. The undulating movement starts in the shoulders, with maximum amplitude towards the hips, the legs almost don't bend to transfer the movement to the monofin. This technique is called the dolphin kick.

Monofins were introduced in the USSR in 1972, by a Ukrainian finswimming club, and have been used for finswimming competitions since, allowing monofin swimmers to reach speeds of 12km/h.

Monofins can be used to swim :

  • at the surface of water, in swimming pools or in the sea.
  • under water without air (apnea)
  • under water with air provided by a compressed air tank.

By slowly oscillating the surface of the monofin when submerged freedivers can generate large amounts of thrust even with small or slow movements. This preserves energy which helps with breathholding (apnea).

To differentiate between the use of monofins and conventional fins, the latter are sometimes referred to as stereo fins or bi-fins.